The same is true of Porter Cable reciprocating saws, which have an extra pin or two that need to be tapped out with a pin punch. These assemblies usually have to come off of Porter Cable saws when replacing a worn out clamp pin (a small, round piece inside the assembly). When replacing the clamp pin, the retaining pin(s) has/have to be replaced as well.

Older Porter Cable recip saw models will have two retaining pins, one that fits inside of the other. Newer models will only have one pin.

All three pins are provided in the retainer kit for this repair, and all of the repair parts for this procedure are very inexpensive as well.

This article provides steps for dismantling and reassembling Porter Cable reciprocating saw chucks, and also includes a demonstration video for this repair.

Tools needed for this repair:

• chuck key or allen wrench set
• hammer
• needle nose pliers
• drive pin punch set
• clamp pin (Part# 648594-00)
• retainer kit (Part# 884696)

The demonstration for this repair is performed on The Porter Cable 737 Reciprocating Saw; although, these repair steps apply to any Porter Cable reciprocating saw with a "quick lock" style blade chuck.

Steps for Disassembly

(Make sure to unplug the saw before beginning this repair, or in the case of a cordless saw, remove the battery.)

1. Remove the clamp assembly "foot."

A chuck key should have come with the saw for removing the boot. If it's not available, an allen wrench set will be needed.

2. Hammer out the retaining pin(s).

There is a small hole on the side of the clamp collar in which the retaining pin(s) sit. Using a small pin punch, carefully hammer the pin(s) until they are almost all the way out the other side of the collar.

3. Remove the retaining pin(s) the rest of the way.

From the other side of the collar, pull the emerging retaining pin(s) out the rest of the way with a pair of needle nose pliers.

4. Slide the chuck collar off.

With the retaining pins removed, the chuck collar should slide off easily.

5. Remove the round clamp pin.

A round clamp pin will be visible inside of the clamp assembly and is the part that needs to be replaced (along with the retaining pins). Remove the clamp pin by turning the saw on its side and giving it a light tap.

The chuck assembly is now disassembled with the clamp pin removed.

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Steps for Reassembly

1. Insert the new clamp pin.

These clamp pins are double-sided and can be installed either way.

2. Reinstall the chuck collar.

There is a spring inside of the assembly that keeps pressure on the chuck collar. When reinstalling the collar, the spring must be lined up with a small hole on the edge of the collar.

3. "Start" the retaining pin(s).

Using a pair of needle nose pliers, position the retaining pin in its hole and tap it in partway with a hammer.

4. Hammer the retaining pins in all the way.

Using a slightly oversized pin punch, hammer the retaining pins all the way back into position.

5. Reinstall the "foot" of the saw.

Replace the saw foot again, making sure to tighten it into place with the chuck key or an allen wrench set.

The saw is now reassembled.

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Conclusion

Please view this article's demonstration video for additional tips on this repair, or simply for the benefit of the moving visual aid.

The retainer kit and clamp pin needed for this repair are compatible in several Porter Cable recip saw models, and can be found by clicking the links.

Otherwise, start your repair by entering your saw's model number in the "Model Number" search field at the top of this page.

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What we're about.

Some switch replacements are very easy, while others can be a little more complicated, or just require an extra trick or two for them to go smoothly.

One common type of switch that often causes problems for D.I.Y. tool repairman is what we call a "trap door" switch. This is because the wires leading in and out of the switch are held in place by a spring. The pressure of the spring on the wires acts like a trap door, and the pressure must be relieved from the wires to get the wires out.

This article explains the best way to remove and replace wires in a trap door spring switch.

Tools Needed

• a small seal pick
• soldering kit
  

The picture above shows a trap door switch and two seal picks of different sizes. The seal pick on the left is too large to fit both inside the wire terminal and to the side of the wires inside, so a smaller seal pick is needed. In general, the smaller the seal pick the better for this repair.

Some instructions that come with trap door switches suggest using a paper clip to push the spring back inside the switch. This usually doesn't work, because the paper clips tend to bend with very little pressure. Using a seal pick is the way to go for removing those wires.

A soldering kit is needed for reinstalling wires into a trap door switch. Repairmen will often try to twist the wires and jam them in there, and, several headaches later, give up.

"Tinning" wires with solder before reinstalling them into these kinds of switches will make it so they just slide right in, and it ensures a better electrical connection.

For a Soldering 101 article-Click here.

That's it for this repair's equipment. Now for the steps.

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Steps for Removing Wires

1. Insert the small seal pick into the wire terminal to relieve the spring pressure from the wires.

2. With the pick still inserted, remove the wire.

In trap door switches, a spring pins the wires down to a copper contact with the pressure caused by its bent shape, as can be seen in the diagram below:

Inserting the pick in the terminal pushes the spring up so that the wire can be removed easily.

Some trap door switches have special windows beneath the wire terminals. The picture below shows this kind of switch:

In the above trap door switch, the three larger, protruding holes are the wire terminals. The three smaller holes beneath are the switch's "windows." These windows give access to the wire spring mechanism.

So, if a trap door switch includes windows like these, the seal pick is inserted into the windows to relieve the spring pressure from the wires. Each wire terminal has one corresponding spring window.

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Steps for Reinstalling Wires

1. Tin the wires with solder.
2. Push the tinned wire into the trap door wire terminal.

With the wires removed, the springs inside the terminals of a trap door switch reset. When reinserting the wires, the best way to ensure that they can overcome that resistance is to "tin" them with solder.

Sealing the wires together with solder will strengthen them so that they can push past the trap door spring, and it makes for a better electrical connection.

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Conclusion

These tricks and suggestions should make it much easier to perform a power switch repair with a trap door switch. Please view this article's demonstration video for more instruction on this repair.

To begin your switch repair, type your tool's model number in the search field at the top of our Home Page.

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What we're about.

Nail guns might be tough, macho, workhorse power tools and all, but, like how the rest of us might need a hot shower, a ball game, and good meal to feel our best after working hard all day, air nailers must be well-serviced between each use as well.

Air nailers break down over time from normal wear. Performance problems can also be caused by incorrect parts, incorrect assembly, misuse, incorrect air pressure and a number of other things. There is quite a checklist to go through if a nailer starts leaking air or if the driver does not retract (for example), but diagnosing can be split up and organized so that the cause is quickly discovered.

This article addresses the most common air nailer problems one symptom at a time.

Unfortunately, most air nailer problems require a part or two to be replaced in order to fix the problem, but the bright side is the most commonly replaced parts are inexpensive. The best way to avoid air nailer problems is to prevent them as much as possible.

Air Nailer Pre-Diagnosis

This section is really about performing air nailer maintenance, checking that the correct air pressure is being used, that the nailer's parts match and are installed correctly, and that the most obvious causes of air leaks are prevented.

These are things that should be "givens" when it comes to using an air nailer. If an air nailer user is confident that these checks and maintenance issues are always in order, then half of the common causes of air nailer problems are already eliminated.

Here's the thing: say, for example, that a nailer's driver starts retracting slowly after a couple of months. As will be discussed below, that could be caused by worn O-rings, mis-sized O-rings, and other parts issues. But, the same exact behavior in the nailer can be caused by something as simple as low air pressure supply.

Since that's the case, the best way to know if there's a part replacement in the near future is to just eliminate the simple issues ahead of times. Most of the major nailer symptoms follow this pattern, that one symptom can either be cause by something simple and preventable, or by a number of more complicated issues.

In that way, these practices of maintaining the nailer and checking its set-up become a set of assumptions that "pre-diagnose" many problems, by eliminating them through prevention.

Later in this article when symptoms are addressed individually maintenance and set-up causes will not be discussed, because it will be assumed that the guidelines in this section have already been addressed, rechecked, and followed.

Correct Air Pressure

Know and check the nailer's operating pressure, which should be found in the owner's manual. If the manual is not available, they are usually available to view online on the nailer manufacturer's website. Most nailers are ran between about 100 psi and 120 psi.

Low air pressure can cause these symptoms:

• the gun doesn't work at all.
• driver won't retract after firing.
• driver retracts slowly.
• poorly sunk nails.
• splitting wood.

High air pressure can cause these symptoms:

• air leaks.
• broken parts or casing.
• heavy wear.

There's never a good reason to run an air nailer at an air pressure setting that goes against its specifications, and many problems can be prevented by always maintaining the right pressure.

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Lubrication

Some nailers are oil-less, but most use oil, have to stay well lubricated, and should be lubricated after each use.

A poorly oiled air nailer can cause damage to parts, and pretty much every symptom in the book, including air leaks, driver jams, pusher guide malfunctions, and nail loading errors. A very dry gun will not fire at all.

Too much oil will become a messy, obvious problem. Nailers only need a few drops each day to prevent many malfunctions. Nailers require special oil used for air tools called Air Tool Oil.

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Correct Parts, Tool Assembly, and Nails

Almost any nailer symptom can be caused by installing an incompatible part or by reassembling the tool incorrectly. So, if a nailer starts leaking air or jamming up, say, after an O-ring replacement, an incorrect part or assembly mistake should be the first suspects.

Most O-ring kits, valve kits, and other parts come with instructions for assembly. Some even have handy color codes that help keep all the rings straight. Be absolutely certain that the correct part is being installed into the nailer before beginning the repair.

Any mistake during reassembly can cause leaks and other break-downs. It is a common mistake to reinstall some of the circular parts backwards. Because the tool is a pressured system, everything must be tightened very well, which is another common oversight.

In general, and depending on the brand and model of the nailer, air nailer repairs can get a little tricky sometimes, so repairs should only be performed when the repairman is very confident. Pushers/guides can be especially hard to reinstall after disassembly.

Nails type is an issue all its own. Sometimes nail jams, misfires, and guide jams are caused by use of the wrong kind of nails. This is especially true of some Hitachi models. Before looking into more complicated causes, make sure that nail type guidelines are followed as found in the user manual.

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Dirt and/or Water in the Nailer

Dirt and/or water in the nailer can also make the tool act up in various ways, from the driver, the magazine, to not working at all.

Dirt will bind up the sliding parts, like the nail feed area, the nose safety, and the driver. A dirty nailer should be cleaned thoroughly, otherwise all that dirt will wear moving parts down in a hurry. The magazine and feed area can be sprayed out with an air hose (make very sure that the air is dry).

If dirt has gotten all the way up inside the nailer, it will have to be disassembled and cleaned. Dirty nailers should be taken to a professional shop for disassembly and service if the user has any doubts.

99% of the time, the only way that water gets into the nailer is through the air supply. Water builds up inside of air compressors from the humidity in the air. Air compressors have a drain valve on their tanks for removing water from their systems. Air compressors should be drained of water before each use.

Water getting into the nailer will cause the same problems that dirt will, and is especially bad for oiled guns. Nail guns should be allowed to completely dry if water has gotten into them. Sometimes this means disassembling the gun so that the water can dry up faster. After drying, it's best to re-lubricate the tool.

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Simple Air Leaks

By "simple," we mean that the air leak is easily resolved by obvious methods that usually don't (except with cracked cases) require parts replacement.

For example, air coming out the bottom of the gun because the air hose is attached too loosely is an obvious air leak: tighten the hose fitting. But air coming out the bottom of the tool because of a worn valve or O-ring is a more complicated leak.

The best way to know if the problem is simple or complicated is to eliminate the simple possibilities, again, through prevention.

Simple air leaks can be caused by:

• loose air connections.
• cracks in the tool casing.
• pressure too high.
• loose fittings around the tool.
• dirt.
• poor lubrication.
  

More specific air leak symptoms are discussed below, and the diagnosis steps assume that simple air leak causes have already been eliminated.

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Specific Symptoms:

Other Air Leaks

If the cause of the leaking air is not one of those discussed above in Simple Air Leaks, then then it most likely involves an internal part. Often, those internal parts have to be replaced because of wear or damage, but sometimes they are just out of position and need to be re-adjusted.

Sometimes the only reason air is leaking from the nailer is because a seal, O-ring, or valve has moved out of place and become "unseated." This cause is difficult to diagnose, especially without all that pre-diagnosing.

If you suspect that parts of the tool need to be reseated, try on of the two methods below.

Steps to "seat" air nailer seals:

1. Dry fire the nailer.

2. Give it a good, solid bump on the back of the tool to reposition those valves and O-rings (This is especially true for some Hitachi models.)

This works especially well for some Bostich model nailers. Air leaking out the back can often be solved be re-seating components.

If the diagnosis comes down to a close inspection of parts (for any model), look for wear and damage like dry/cracked O-rings, worn valves, bent and/or kinked springs, look closely for little pin-sized holes in O-rings and seals, and check that no part of tool is bent or warped.

Most of the time, when a part is causing an air leak, it's an O-ring, which is good since O-rings, and O-ring kits are inexpensive. It's a good idea to have a kit around for fast repairs if they are available.

Air Leaks Out Nose

Like other leaks, air coming out the nose of the gun may just be a sign that seals need to be re-seated, so try giving it a bump and dry firing it first.

If that doesn't work, then the cause of air coming out the nose of the gun is probably because of one of two things:

1. The nailer's nose piece is worn, damaged, and needs replacement.

2. An O-ring, or other part somewhere in the forward part of the gun is worn or damaged and must be replaced. Disassemble the nailer and inspect its parts for damage/wear or take it to a shop.

Air Leaks Out Vents

Try "seating" seals and valves first with a good bump.

If that doesn't work, then the cause is most likely a damaged or worn part, like an O-ring or valve. Disassemble the nailer and inspect it parts for damage/wear, or take it to a shop.

Air Leaks Out Back

This is a good sign that seals need to be reseated with dry firing or bumping the gun, but it is also possible that air is leaking out the back of the tool because of a broken part.

If attempts to reseat the seals fail, the tool will have to be disassembled and inspected for wear or damage to parts.

Air Leaks Out Trigger

Good news and bad new with this one. The good news is that when air leaks out the trigger of a nailer, it's easy to diagnose. This is almost always caused by a worn trigger valve.

The bad news is that trigger valves are never sold separately, so the entire trigger assembly must be replaced.

It's possible that air could leak out the trigger because of damage to some other part, but very unlikely.

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Driver Does Not Retract or Retracts Slowly

Again, an incorrectly retracting driver can be caused by some of the issues covered in Pre-Diagnosis (and is most-likely caused by those problems: dirt, lack of lubrication, etc.), so it's best to go through that checklist first.

However, like air leak problems, driver issues can be caused by reduced internal pressure from worn or damaged parts.

Take a look at the parts around the driver and piston cylinder. Seals and O-rings are the most likely suspects. Damaged O-rings in this area are likely to have little holes in them.

Take the nailer to a shop when there are any doubts about disassembly, parts installation, or reassembly. If an O-ring kit is available for the air nailer, it's a good idea to keep one around for this reason. If not, O-rings will have to be matched and purchased separately.

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Pusher/Guide Not Working Correctly

Dirt and other issues covered in Pre-Diagnosis can make the pusher run slowly or not at all.

Other causes:

• magazine is bent.
• loader springs bent, worn, or kinked.
• guide channel is too narrow.
• guide is broken.

The most common ways that magazines become bent is through misuse. Workmen will often use the magazine of the nailer to "set their work." That's a nice way of saying that they use their nailer like a hammer and really beat it up.

Over time, this kind of use will bend the magazine and increasingly slow the guide until it doesn't move at all. A bent magazine should go to a shop and/or be replaced. Magazines can be especially difficult to reassemble, depending on the brand.

Check the loader springs for damage, and replace any that need replacing.

If the guide channel has become too narrow, they can often be carefully widened by wedging a screwdriver between the groves and leveraging a little pressure to spread the groove.

If the guide is broken or heavily worn, it will have to be replaced.

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Double Fire

Double fire is usually caused by one of three things:

1. The nailer is not being held down with enough pressure when the nailer is fired.

2. The trigger valve is leaking and not releasing fast enough for a single shot.

3. The pressure fire feature on the nose of the gun (if applicable) is inoperative.

If adding pressure does not help, then it is most likely the trigger, which will have to be replaced. For guns that use a press-and-fire system, the spring in the nose of the gun may be worn, causing the ejection of an additional nail.

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Conclusion

The issues and symptoms discussed in this article are very common to air nailer use. Even with the right use, maintenance, and prevention, air nailers will eventually need repairs and replacement parts, like most other power tools.

The great thing about a good nailer is that it can last a lifetime with the minimal expense and hassle with the right know-how.

To get started finding a nailer part for a replacement repair, visit our Nailer Parts page to find your air nailer by brand and model. Or, type the nailer's model number in the search field at the top of this page. Good luck with your repairs!

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What we're about.

We get a lot of questions about our guidelines for seasonal tool and machine storage, and this article is here to spell it out.

For most tools and machines, winterizing them means attending to the following five areas:

1. Fuel Service
2. Maintenance
3. Battery Service
4. Cleaning
5. Storage

Below is a detailed description of each of these winterizing procedures.

Fuel Service

Gasoline doesn't keep well over time. Simply leaving remaining fuel in a tool or machine over a season can really gunk it up.

One of two things should be done with gasoline tools and machines before storing them:

1. The fuel should be emptied, and stored empty for the season. Or,

2. The fuel should be topped off and have a fuel stabilizer added to it.

Actually, a rather furious debate revolves around which of these two methods is better. Our eReplacementParts.com tool repairmen report that they see equal numbers of cases of fuel storage problems from resulting from both methods.

Ideally, a gas power tool would be stored with about a half tank of fresh fuel (with the addition of stabilizer), ran periodically during the winter, and periodically have more fresh fuel added to replace the old fuel; however, this is pretty impractical for most users.

We maintain that both of the above methods work equally well for storing gasoline power tools.

Lastly, before storing a gasoline machine, make sure that the fuel shut-off is switched to the "off" position, to restrict fuel to the fuel tank.

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Maintenance

Most of the recommended maintenance for winterizing tools and machines is actually optional. It's just that the season changes serve as a good time to get in the habit of sticking to a maintenance schedule.

Here's the list of possible maintenance:

• Change the oil.
• Replace spark plugs.
• Lubricate cylinders with a small amount of oil.
• Clean or replace filters.
• Tighten screws, belts, and other parts that need it.

Things like spark plugs don't have to be replaced every year, but putting it off is usually an opportunity to forget.

In general, because things like oil, filters, and spark plugs are relatively inexpensive, a tool or machine is just better off for the slight maintenance overkill.

As the years go by, you'll see the difference in how your tools and machines hold up with just a little extra effort.

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Battery Service

First, batteries should be disconnected from their motors before storage, and cordless batteries should be removed from the tool.

If the machine has a large, water-holding battery (similar to those in cars), then it's also a good idea to top off the water level with some distilled water.

Cordless tool batteries should be charged to full before storage, and, ideally, charged every 30 days or so while being stored.

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Cleaning

This is especially important for lawn & garden and other outdoor tools, since they tend to get more dirty. Over time, buildup of dirt and organic material can wear down the surfaces of machines, and in some cases, cause performance-related issues.

Here's a short list:

• Wipe or spray off any grass, dirt, grease, grime, and organic material. For lawn mowers, make sure to clean the whole underside of the cutting area.

• When the cleaning gets tough, use a brush.

• After cleaning under lawnmowers especially, many users prefer to spray the underside with some kind of lubricant to protect it from rust and make the surfaces more slick against future buildup. Machine owners recommend everything from silicon, to WD-40, motor oil, and cooking spray. Take your pick.

• Once they're clean, protect blades and other cutting edges with some kind of lubricant.
  

• Chips in paint can also be brushed up a little and then coated with lubricant to prevent rust.

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Storage

Storage is simple. Keep tools and machines in a clean, dry place that is well-ventilated and protected against outside elements. Keeping tools in a garage is best whenever possible, so that they'll be stored closer to room temperature.

Water is the biggest concern for tool storage, so if you think the ground might get wet, hang them up when possible.

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Conclusion

Once a few winterizing steps are accomplished, you can rest easy throughout the season knowing that your tools and machines are in good order.

It's also great to start the summer season with the bulk of tool and machine service already completed.

View our Power Tool Care and Maintenance article for more tool care tips.

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What we're about.

Trimmer clutches need to be removed when replacing the clutch drum, replacing other clutch parts, and when the trimmer starter needs to be accessed for repairs, service, or replacement. Removing the clutch drum is a little tricky, because turning the clutch drum screw will only turn the piston unless the piston is somehow bound up.

Detailed steps and pictures are included in this article that explain how to remove a trimmer clutch and how to keep that trimmer piston from spinning.

For more information about line trimmers: Click here for a Line Trimmers 101 article.

Tools needed to remove a trimmer clutch:

• needle nose pliers
• screwdrivers
• #25 torx driver
• 3/4" socket and wrench
• adjustable spanner wrench
• a piece of nylon rope

For this demonstration, we remove the clutch from a Ryobi SS30 String Trimmer, but the majority of trimmer clutches are removed in the same way.

Empty the Gas from the Trimmer

To safely remove the clutch drum and perform other repairs, all of the trimmer's fuel should be emptied before beginning.

• Open the fuel tank and safely dump any gas out.
• Pump the primer a few times to clear extra fuel from the system.
• Replace tank cap and try to start the trimmer up. If it starts, let it run until the remaining fuel is used up.

With the fuel removed, the trimmer is ready to be dismantled.

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Steps for Removing a Trimmer Clutch

The first objective in removing the clutch drum is to separate the trimmer shaft from its motor.

1. Remove the screws holding the shaft to the motor.

• Screws and other fasteners that hold the motor to the trimmer shaft must be removed.

For the Ryobi SS30, this means unscrewing four #25 torx screws from the motor assembly.

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2. Disconnect motor wires leading to the switch.

• Motor wires need to be disconnected in order to completely separate the motor from the shaft.

This is best done with a couple pairs of needle nose pliers.

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3. Disengage the throttle cable from the carburetor.

The throttle cable is usually held into place by a screw and a pin that connects it to the carburetor.

• Remove the screw with a screwdriver.
• Free up the pin by removing it from its hole with a pair of needle nose pliers.

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(HINT:Now that the motor is completely removed from the trimmer shaft. The next step is to remove the clutch drum screw holding the clutch drum onto the motor.

This is the only tricky part involved in removing the clutch. To remove the clutch, a screw must be removed from the hole in the clutch drum that connects the drum to the motor.

To remove the clutch drum screw, the trimmer's piston must be bound first. Otherwise, turning the drum screw will only rotate the piston, and the screw will not come out.

To bind up the piston, it must first be accessed by removing the trimmer's spark plug.)

4. Remove the trimmer's spark plug to access the piston cylinder.

• Pull the spark plug cover off.
• Using a 3/4" socket and ratchet wrench, unscrew the spark plug and remove it

You should be able to see into the piston cylinder now.

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5. Bind the piston with a piece of nylon rope.

The trimmer piston has to be bound, otherwise, turning the clutch drum screw to remove the clutch drum will only turn the piston.

• Stuff a short piece of nylon rope into the cylinder, leaving some hanging out so it can be easily removed.
• Slowly pull the starter cord to bring the piston up.

When you feel resistance in the starter cord, you'll know the piston is bound enough to remove the clutch drum screw.

Now the drum screw is ready to come out.

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6. Unscrew the clutch drum screw and remove the clutch drum.

• Unscrew the clutch drum screw, located in the hole at the base of the clutch drum.
• Clutch drum screws are regular thread, and turn counterclockwise to loosen.
• Remove the clutch drum.
  

For the Ryobi SS30, this screw again requires a #25 torx driver.

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7. Remove clutch plates.

• Using an adjustable spanner wrench, unscrew and remove the two remaining clutch plates.

The clutch and clutch drum should now be removed, and the starter of the trimmer should also be accessible.

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Conclusion

The key to removing a trimmer clutch is binding that piston up with a nylon rope. To begin your trimmer repair, visit our Trimmer Parts page to find your trimmer by manufacturer. Or, type your trimmer model number in the search field at the top of this page.

See our Finding Tool Model and Type Numbers article for more information about accurate parts searches.

Thanks for taking advantage of this and other eReplacementParts.com tool and machine information resources.

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What we're about.

Although an essential skill, the soldering needs of tool repairmen are relatively simple and only take a little practice.

This article discusses topics about soldering and solder related products, focusing mostly on how they apply to tool repair. This article also offers general steps for making good solder joints.

Even though it is probably review for some readers, we'll begin with a very short description of what soldering is and how it works.

What is Soldering?

• Soldering is a process of joining two metals together (usually electrical components) without having to actually melt the base materials (as in welding).
  

• Instead, a soldering iron/gun is used to melt a filler metal (solder) at relatively low temperatures without the high risk of heat damage as with welding and brazing.

• The liquid solder spreads between the contact points being connected.

• When the solder hardens, a strong, electrically-conductive bond is made between the two base metals.
  

As the solder hardens, it spreads across the material with which it is making contact, seeming to move on its own. This spreading across a contact surface is a quality shared by all liquids called "wetting" or "wicking" (although some liquids "wet" better than others). Alloys and other solder materials are selected, in part, for their ability to wet quickly.

Quick wicking allows the melted solder to fill up tiny spaces between parts and microscopic "imperfections" on the surface of the contact material before it hardens, creating a micro-tight hold.

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Soldering Tools, Materials, and Accessories

Now, with an idea of what soldering is and how it works, the next step is to go down the list of tools and materials needed for soldering.

Here's a list of the bare minimum equipment needed for soldering:

• a soldering iron, gun, or torch.
• solder
• flux
• cleaning materials (depends on the job), and
• de-soldering tape

This section addresses each of the above soldering essentials, options available on the market for each item, and which is best for the soldering tool repairman.

Solder Irons, Guns, and Torches

One way or another, the solder is going to have to be heated in order to melt. Soldering irons and soldering guns are the two most common devices used for heating solder, although torches and air pencils are sometimes used.

For choosing soldering irons and guns, the most important step is to match the wattage of the heating device to the size of the soldering job. More wattage does not mean a hotter gun; more wattage only means that the gun or iron will be able to efficiently melt more solder.

If wattage is too low, then the iron or gun will not melt the solder fast enough for it wet and cover the contact surfaces correctly, and the solder joint will be weak. If wattage is too high for the size of the job, then the extra heat coming from the iron or gun is likely to damage components surrounding the soldering area.

For example, 15-30 watt irons tend to be best for small soldering, like circuit boards, 40-100 watt irons are usually used for soldering in audio equipment, and 100-200 watt irons and guns are preferred by tool repairmen for power tool soldering.

Really though, there are no definite rules outside the preference of the user. As we discuss below, if an iron is not hot enough to make good joints, you'll know it. As long as a gun or iron has enough wattage for the size of its work and is not damaging surrounding parts, solderers should use what is comfortable. Power tool repairmen tend to prefer higher power solder guns over lower power irons, for faster work.

More expensive, temperature controlled irons are available for applications where constant temperature is important, but temperature controlled irons are needed seldom (if ever) by tool repairmen, since fixed temperature irons work fine.

Soldering guns and irons are also available in portable and non-portable versions, and they can include other features and accessories. These include differently-shaped tips, stands for the gun or iron, clamps for holding work in place, a temperature gauge, and, sometimes, a heat boost button.

These features and accessories are pretty self-explanatory, and because only the most ordinary kinds of irons and guns are needed for tool repair, they are not necessarily essential for tool repair soldering.

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Solder

Solder is the filler material that is melted in soldering to make a joint between contact areas. Solder materials are designed or chosen for their low melting temperatures, quick wetting action, and fast hardening. Most solder types are either alloys or other mixtures of metals.

Now, this is where things can easily get overcomplicated for a soldering tool repairman. A little research will quickly reveal that many kinds solder materials are available for many soldering applications, and each is a little different. Solder comes in combinations of tin-lead, lead-silver, tin-silver, zinc-aluminum, tin-zinc, cadmium-sliver, and tin-bismuth, to name a few.

Tool repairmen can forget all that and simply look for common solder products advertised as multi-use or multi-purpose solder. These will generally be tin-lead or tin-bismuth combinations, the most general-application types of solder.

Other than choosing an average solder, tool repairmen have two more decisions to consider about solder products:

1. Lead-free or not lead-free, and

2. Rosin or no rosin.

First is the issue of lead. For environmental and health reasons, solder manufacturers are producing more lead-free soldering materials.

For health reasons, lead-free solders are best when children could possibly have access to it. As far as the environmental concerns about lead, opinions and level of concern vary, so it just comes down to the preference of the repairman.

Second is the choice between solder that includes flux, and flux-free solder. Rosin is one kind of flux, and most flux-containing solders use rosin. Although having rosin included with the solder promotes stronger joints by preventing oxidation, repairmen tend to like rosin-free solder since its usually best to flux separately anyway, regardless of the solder type being used.

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Flux

When solder heats up, the heat given to it by the iron or gun gives the metals in the solder some of the energy they need to react with oxygen in the air. This is an oxidation reaction that produces byproducts, impurities, which can weaken the strength of a solder joint. That's where flux comes in.

Flux paste is made of or includes materials called "reducing agents," which reverse the chemical reactions involved in oxidation when heated up. Flux prevents impurities from forming through oxidation when it is used to coat solder and contact surfaces, and it also reverses oxidation that has occurred. Flux is inactive at room temperatures.

Keeping solder and base metal "clean" of oxidation impurities is important, because the solder cannot adhere to the impurities as well as a clean metal surface. Soldering without flux, or using flux incorrectly, will make solder joints weak.

Flux that contains zinc chloride and/or ammonium chloride should be handled with caution (gloves and goggles recommended). Also, fumes from heated or burning flux can be toxic, so good ventilation is important when soldering.

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Cleaning Materials

The first step before any soldering job should be to make sure that the solder and base metals are clean. Cleaning is not needed for most small, electronic work, but it is occasionally necessary.

Wire brushes and small sponges work well for wiping rust, dirt, grease, and other impurities from components. Tool repairmen and other solderers recommend different cleaning materials and methods, but the important part is just that the surfaces are clean. Some solder joints will require cleaning of flux residue after completion as well.

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DeSoldering Tape

Desoldering tape also goes by the names "desoldering braid," and "desoldering wick." These tapes are usually made of braided copper that contains rosin flux.

Using desoldering tape is the best way to remove old solder joints without damaging surrounding surfaces and components.

To remove solder with desoldering tape, the tape is held against the solder joint to be removed, and then heat is applied to the tape (not the joint). As the desoldering braid heats up, it will pass heat to the solder joint until the solder is hot enough to melt. Once melted, the liquid solder will automatically flow onto the clean wick.

Using desoldering tape is also a good way to clean contact surfaces of impurities before soldering, and having some handy is a must anytime a solder joint needs to be removed.

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Steps and Tips for Good Soldering

These basic steps for soldering apply to soldering of all types. General steps for soldering are:

1. Clean all surfaces.

2. "Tin" wires and soldering iron/gun.

3. Apply flux.

4. Heat and apply filler (solder).

5. Remove heat and hold still until solder cools.

1. Clean all contact surfaces.

For solder joints to hold, all contact surfaces must be clean and free of oxidation. Cleaning wires and base metals can be done with sponges, wire brushes, and cotton swabs.

2. "Tin" wires and soldering iron/gun.

When talking about soldering, "tinning" means to coat with solder. In order to create the strongest joint possible, each contact surface needs to be equally hot enough to melt the filler material. Tinning the soldering iron/gun and wires allows heat from the gun to transfer to other surfaces more easily, so that the solder melts quickly and completely when touched to the hot base materials.

3. Apply flux.

The best way to make a bad soldering joint is by soldering without flux. After tinning, flux should be applied to each contact surface, including base metals and wires. Flux can also be applied to the tinned soldering iron/gun, but it is not completely necessary.

4. Heat contact surfaces and apply filler (solder).

Heat should be applied to base metals and contact surfaces before solder is introduced. That way, the metals should already be hot enough to melt the solder when it touches.

Solder should be applied to hot contact surfaces, not to the soldering iron/gun. By applying solder to the hot materials where the joint will be made, the solder is allowed to wick (wet) directly onto the spot where it needs to solidify.

Also, attention should be given to how much solder is being used. Using less solder tends to make better joints.

Applying solder directly to an iron or gun is bad joint waiting to happen. Applying solder to cold contact surfaces will also create weak joints. Again, contact surfaces should be heated first, and then solder should be applied to the hot contact surfaces, never to the gun or iron.

5. Remove heat and hold still until the solder completely cools.

Once the solder has wicked onto the base metals, the connection must be held very still until the joint completely hardens. This should only take about 3 seconds. If a joint is moved before its solder hardens, even slightly, the movement can severely weaken the joint.

Here are some extra tips about good soldering:

• Cleanliness. Only solder surfaces that are clean, and keep the tip of your solder iron/gun clean.
• Use the correct wattage iron or gun for the job. Over or under heating the solder can make bad joints or damage components.
• Always pre-tin the tip of the iron or gun before soldering.
• Always use flux.
• Always apply solder to the work, not to the iron or gun.
  
• Be patient, especially at first.
• If it makes it easier, secure the work when possible (soldering clamps come in handy for this).
• Practice. Even though the steps sound simple, good soldering takes practice.
• Good solder joints will be smooth and shiny.
  
• Poor solder joints will be dull, crinkled, and/or look otherwise contaminated.
  

Bad Solder Joint Example:

Good Solder Joint Example:

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Conclusion

If you're just starting out with tool repairs that involve soldering, or if you're new to soldering in general, it will probably take a little practice before joints start looking smooth and shiny.

Either way, getting on top of soldering practice and technique is worth the time and effort. Common tool repairs, like replacing power switches, often involve a little soldering, so having the experience and equipment around is a good way to keep tools running well. For a "Power Switch Repair" article–Click here.

Other repair tips and suggestions are available through eReplacementParts.com's repair forum and discussion board features, information tools that address machine and tool part replacements and other services issues. Good luck with your soldering and tool repairs!

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What we're about.

Major parts involved in dismantling and reassembly are the Bit Holder Assembly, Gear Housing, Hammer Piston, Striker, and Ratchet Sleeve and Toothed Shaft Assemblies.

The tools required for this project are a screwdriver with a #20 Torx driver bit and a standard flat-head screwdriver.

Video Links

Please view our instructional videos on right, or view them on our YouTube page by clicking the links below:

How to Take the Hammer Drill Apart

How to Put the Hammer Drill Back Together

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What we're about.

This article has a video and step-by-step instructions to demonstrate this. Milwaukee's instructions are also below the video.

*These instructions apply only to model numbers 6519-22, 6520-21, 6521-21, 6523-21 and 6536-21 Sawzalls with QUIK-LOK® Blade Clamps.

Tools needed to remove the blade clamp assembly are:

• a hammer, and
• a flat-head screwdriver.

REMOVING THE QUIK-LOK BLADE CLAMP

1. Remove external retaining ring (7) and pull front cam (6) off.

2. Pull lock pin (1) out and remove remainder of parts.

REASSEMBLY OF THE QUIK-LOK BLADE CLAMP

1. Coat new lock pin with powdered graphite.

2. Hold tool in a vertical position.

3. Place spring cover (2) onto spindle.

4. Slide torsion spring (3) onto spindle with spring leg 90 degrees counterclockwise from the hole in the spindle.

5. Slide sleeve (4) onto spindle aligning hole on sleeve with hole in spindle.

6. Slide rear cam (5) over sleeve until it bottoms on sleeve shoulder, ensure spring leg inserts into hole in rear cam.

7. Rotate rear cam counterclockwise until there is a clearance for lock pin (1) to be inserted into sleeve/spindle holes. Insert lock pin.

8. Align front cam (6) inner ribs with rear cam outer slots and slide front cam onto sleeve until it bottoms. Retaining ring groove should be completely visible.

9. Attach retaining ring (7) by separating coils and inserting end of ring into groove, then wind remainder of ring into groove. Ensure ring is seated in groove.

10. Blade clamp should rotate freely. During normal usage, debris may prevent blade clamp from rotating freely.

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What we're about.

This article has a video and step-by-step instructions to demonstrate this.

Only a few tools are needed to remove the blade clamp assembly:

• a hammer
• a metal punch, and
• a small flat-head screwdriver

Step-By-Step Instructions

1. Assemble parts 1 through 6 on to the shaft as shown in the graphic below.

2. Compress and rotate counter-clockwise (1/2 turn) the Collar 4 and the Sleeve 6 until the radial slot 9* on the Collar, and the notch 7* and slot 8* on the Sleeve, all align with the hole 10* on the shaft. Be sure that both the collar  4 and the sleeve 6 make the 1/2 turn. A common mistake is to rotate only the collar.

3. With all the slots and hole aligned as described above, insert the Detent Pin 11 completely into the hole 10 (flat side first, pointed end towards you). Insert the Retaining Pin 12 just enough to clear the Sleeve 6 and engage the shaft hole. If the Collar 4 is locked and will not rotate in either direction, proceed to step 4. Otherwise, skip step 4 and go to step 5.

4. While holding the Retaining Pin 12 in place by hand, compress the Sleeve 6 inward (DO NOT INSERT A BLADE) until the collar releases and rotates clockwise.

5. The Retaining Pin 12 should now be pressed in until it stops, but only after wedging the tip of a flat blade screwdriver into the slot where the blade would normally go to avoid collapsing the shaft/blade opening.

Align all parts before inserting the Detent and Retaining Pins

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What we're about.

One good example of this is with power switches. Many manufacturers have replaced old, 4-terminal power switches in their tools with new, 2-terminal power switches.

Even though the wiring for these two kinds of switches is different, the new, 2-terminal switches can be wired easily, even in if the tool previously used a 4-terminal switch.

Generally, tool and machine manufacturers purchase small components like switches in bulk from an electric wholesaler. Sometimes the wholesaler will change the style of the component, or manufacturers will make a change in the interest of cost or quality. For example, 4-terminal switches are slightly more expensive than 2-terminal switches, and the idea is that the cost savings are passed to the customer as well.

Below are diagrams and explanations for wiring 2-terminal switches in tools that previously used a 4-terminal switch.

For more information about Power Switches–Click here.

For a "Power Switch Repair 101" article–Click here.

4-Terminal Switch Wiring

4-terminal switches have two wires leading from the motor and two wires leading from the power cord.

Below is an example diagram of a 4-terminal switch. The cold, or negative wires are the filled in black power cord wire and the corresponding left-hand side motor wire.

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Wiring for a 2-Terminal Switch

Changing the wiring from a 4-terminal switch like the one above to a 2-terminal switch is pretty simple.

Like in the below diagram, the positive wires from the cord and the motor are connected to the switch where the electrical connection will be completed and cut by using the switch trigger.

The negative wires from both the motor and the switch should be connected with a tie together, allowing for a full circuit when the switch is used to connect where the circuit is severed.

It is always important to thoroughly test a power tool after installing any new component, especially in the case of a switch re-wiring like the one described above.

If the power tool features a rotating spindle it should be checked that it is spinning in the correct direction. This is especially important with routers and saws, because a bit or blade rotating in the wrong direction can be very dangerous.

If the tool is spinning in the wrong direction, it may be because the switch wiring was reversed during the procedure. Reversing the motor wires on the switch will reverse the polarity and get the tool spinning in the right direction.

Drawing a wiring diagram is the best way to prevent this kind of mix-up. For more about Wiring Diagrams–Click here.

If you're looking to replace your tool's power switch, you can begin your search on our Home Page, or by using the "Model Number Search" at the top of this page. eReplacementParts.com offers easy search features and fast shipping options, so you can get the power switch you need, apply this article's repair steps, and get your tool or machine up and running again.

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What we're about.