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Discussion
Discussion for the Bosch 4000 (0601476139) Table Saw
Hey, thanks all for the info on the Bosch 4000 and the video on techniques for pulling the bearing. One problem, in using the 2 flat drew drivers to pop the bearing, it disintegrated. Now I have just the most inner hub of the bearing on the armature shaft; not enough to get a bite from the screwdrivers. I'm going to try grinding the remaining ring down to the point I can use a chisel to break it off unless somebody has a better idea. I don't want to nick the shaft but can't think of anything else.
Hi Greg,
Don't use a chisel.The best way if you don't have a puller is to use a dremel tool with a cut off wheel and carefully cut the inner race off.Generally one cut on the side of the race and you can pull the race off with your fingers.Hope that helps.Good luck.
Tinker
I bought a used saw that was missing the blade guard. I like the saw but I'd like to have a guard. I don't see one on the parts list or the picture. Can you hel?
Thanks!
order a new housing an it seems to be a little short can some one take a measurement i'm measuring 5 3/4" long i think they my have sent me the wrong housing
I have a bosch 4000 table saw and when i turn it on it runs for 2 minutes then turns off then comes back on for 15 seconds then off and pretty much repeats this pattern. Can anyone help me figure the problem out im outta ideas.
My saw suddenly stopped working partially through ripping a 2x4. The motor hums and the blade will spin just slightly(like a 1/2" at a time) when turned on. The arbor won't turn under finger pressure.
I haven't found this specific issue in the forum and am in the process of disassembly which may reveal the problem but if anyone has some insight it would be greatly appreciated. Thank you.
It was the bearing on the field side of the armature. It is frozen up solid with a bulge on the side. My new question is do I need to disassemble everything on the blade side to get the armature out? I was going to replace both bearings while I had it apart. Thanks in advance for any help.
Reply: Bosch 4000 Arbor Won't Spin
Tinkerdave
Hi gettes,No you should just be able to take the brushes out and remove the four screws that hold the motor housing to the front bearing housing and slide the housing off the armature. You really don't need to replace the larger front armature bearing as this almost never goes bad.Make sure your blowing the motor out with compressed are on a regular bases as this keeps saw dust from clogging the cooling vent in the rear of the housing. Hope that helps.Good luck.
Tinker
I have had the bosch table saw for a number of years. Lots of miles of ripping everything. It seems to not have the power it use to. I have to baby it, if I am ripping something pretty thick, it will bind or stop. Could someone tell me where I should start looking or replacing? Also when I tilt the blade to cut a 45, the blade hits the lower bar underneath the table when I start it up?
Thanks so much for the quick reply, Tinkerdave. When you say "control module" if you are talking about item #12 "speed control" on page B above, that is what I replaced. I bough if from this web site. I am absolutely certain I wired it correctly. More details: A piece of wood got crooked and bound up for less than a second before I threw the switch off. I've have much worse binds than this on other saws with no problems. But when I pulled the wood out and turned the saw back on, the saw did as I described: It turns backward for an inch and stops. A current-hum sound comes out of the the motor but I don't let that go for more than a half second before flipping the switch off. If I grab the blade and spin it forward as hard as I can and then flip the switch on, it will turn very slowly for several revolutions and sort of clatter until it stops. Those are all the details I can think of. Thanks in advance for any advice.
Hi Joalmorris, based on what you tell me I can't think what else it could be.I've had a number of saws that have come into the shop most have had something like that happen to them. The saw will run in reverse,the saw will run at a high rpm,or run and chatter like your explaining. I still believe you got a bad speed control. The control unit does a number of things 1. it controls the speed brake. 2. It is a RPM limiter.3.It controls the soft start. It sounds like the controller is stuck in soft start and brake at the same time.The only other thing that could cause this is if the brake lead from the field is broken so the controller is not getting a signal from the field and thats whats causing it to be wonky.
Out of the blue my table saw stopped working. When I turn it on, the blade turns backward about an inch and then stops. The motor continues to hums like it wants to run. I turn it off immediately. I've read through the advice below and most people think the speed control is the problem. Well..I bought a new speed control and replaced it. It still does exactly the same thing. Does anyone have a Plan B suggestion for me?
Hi Joalmorris, The fact that the motor tries to turn backward and then stops and hums leads me to believe also that your control module is bad.The control module is trying to apply the brake and this is why you have slight movement in reverse.Bosch has had problems with this module and we have even gotten them bad out of the box.Are you sure you have it wired back up right. Did this problem just suddenly appear or did you notice the saw doing other things also.As much information as you can give will greatly increase the chances that someone can pin down what wrong with it.sorry I cant be more helpful.
Tinker
Here is an article and video that I hope will answer any question you might have in removing the bearing from the armature. How to remove a bearing with a vise.
I have a Bosch 4000 Table saw, it is between 2 & 3 years old. Serial # 79114 1060.
Well looked after, little use, never got wet. I was using it yesterday to make some rip cuts on some trim. I had just started a cut when the power tripped out, the motor was not being overloaded. I re-set the switch on the consumer unit, and when I re-started the saw it now only turns backwards and at approximately half speed!!!
I have plugged other tools into same socket without the same result and I have plugged the saw into a different socket with, unfortunately, the same result of backwards and slow!
Do you have any ideas what has happened to my saw?
What is the warranty issue on the motor, which seems to me to be the issue?
How much is a new motor and can I fit it easily?
Any help or advice would be greatly appreciated before I take it to a repair centre.
Hi Simon, Your speed control unit is bad.The reason its turning backwards is this controls the brake which reverses the motor for a fraction of a second the brake is stuck in the on position.Replace the speed controller and this should fix your problem. Hope that helps.good luck
Tinker
Reply: Bosch 4000 Table Saw PROBLEM
WJA
Hello Simon,
I agree with Tinkerdave with his assessment of your problem. The speed control on that saw is the cause of a few problems with the motor on that saw.
WJA
Reply: Bosch 4000 Table Saw PROBLEM
D29
Bosch 4000 table starts and runs backwards slowly! changed speed control still have same problem any suggestions?
Hello my Bosch 4000 is great, but the motor has stopped working. Switch is fine, and the armature looks fine as well as the brushes and commutater. I am left with one thought, could it be the speed control? Will the speed control cause the motor to stop working?
If all the electrical components have all check okay. Your best bet would be to replace the speed control. It is a PC board that controls the motor's speed when under a load and gives you optimum power when needed. It has in it a circuit breaker/overload to protect the motor from overheating and damaging it.
Hope that helps,
WJA
Reply: Speed Control
mendingshed
Usually if the motor is running slow and backward it is because the crossover wire in the field has shorted out and the field not the speed control will need to be replaced.
the speed control will not make it run backward. that is cause by the field being shorted out.
I really like the features of the saw. Motor is a different story. Right now I have replaced the brushes since the motor did not run correctly, this being only several hours aftergetting it repaired. What could cause this? Sounds like Bosch has major problems with motor units. Need some direction.
Thanks
Not knowing the problem you are having with your saw motor. We have noticed in the past, problems with the PC board failing. When this happens there are several things that could happen. For instance loss of power, motor not running at all, & motor running backwards. If your brushes are wearing out and you are seeing arcing from the motor you might also have a defective armature. I hope this helps.
I have had my saw (model 4000) about 2 years and have had no major problems at all until recently. It seems the fence has become more loose than normal. When I move it using the front locking handle, the rear of the fence is very loose and moves a considerable distance before being locked in place which throws off my measurements and I have to keep readjusting to get it set where I need it.
I have adjusted the rear screw tighter but it then tightens so much it rocks the fence off 90 degrees to the table. Anything looser and it won't stay on my mark because of the rear of the fence moving so much. When it is locked down it sometimes moves toward or away from the blade and will bind the wood between the fence and blade. Can the fence be rebuilt or am I not adjusting it right? Thanks for any help that you can give me.
Occasionally, while running, the saw will make a cracking sound. And then on shutdown, it makes the same sound while decelerating. The small bearing on the arbor shaft seems a bit loose, but I'm not sure if it's my imagination. I replaced the armature bearings; so based on this very short description, do you think it is gear out of alignment because of bad bearing? They both rotate smoothly and make no sounds while in my hands, but no way to test at speed. I'm afraid to put new bearings in and then have to take it back apart to find the gears need replacing or whatever. Thank you
The motor had a chattering noise when first starting then it stopped running so I changed brushes. It still will not run. There is power through the switch, I have not checked the soft start circuit board. It doesn't make a noise when turned on.
The chattering noise could be caused by a damaged commutator. Remove the brushes and slowly rotate the blade while looking at the commutator. Any damaged or missing pads on the commutator could create the noise you heard and cause teh motor to no longer operate.
I am very happy with this saw. I think I dropped a bolt some where. When I try and elevate and drop the blade it gets progressively harder to turn. Nothing appears bent, just not sliding along the guide rods smoothly. If you unplug the saw and manually pull up on the motor/blade is elevates fine.
I think I see where the screw popped out but I can't locate on the diagram.
Smoke from the motor is not a good sign. You would need to dis-assemble the motor to make an accurate diagnosis but there is a good chance that either the armature, field or both have been damaged. If so these components would need to be replaced.
I want to connect a vacuum system to the rear discharge chute, (Bosch 4000) however I don't see this part on any diagram. Is there a part to connect to the discharge pipe and or a kit to connect to a vacuum system? I need to catch all the saw dust to reduce saw dust for inside use.
On the back of your saw there is a discharge chute. The opening on the chute is 2.5" which is the standard shop vac hose size. There are various adapters commonly available that will adapt from the 2.5" opening to common dust collector sizes such as 3" or 4".
I have a Bosch 4000 table saw that has stop working. I have traced the problem to the speed control board. What does this board do and can I bypass it?
The motor would run at a higher speed - this board regulates that. It also is responsible for the slow start that you need, otherwise it would put a lot of stress on the gears.
How do you assemble the spindle lock spring. I needed new armature bearings and disassembled this part unnecessarily. I have two shoulder screws, a lever, and a spring. I cannot get them assembled.
I have a Bosch 4000 table saw. A wire came disconnected coming off of the control board. There are 2 black and 1 blue wire. 1 black goes to the armature. Where does the other black wire go?
My saw started running like a loose wire then it stopped and it
started to smoke smelt burning. I took off the plastic brush
screws but found the inner connector with a cable connection. Not
sure whats damaged.
I have a 4000-n -rt table saw. I bought this saw as a reconditioned saw. Lately I've been hearing this squealing noise when the saw is running and when I shut it off. I think its a bearing but I'm not sure which one . Can you give some guidance on what to do. I'm mechanically inclined and I didn't want to tear it apart without knowing which way to go.
I would agree that it is likely a bearing. It could be any one of the bearings in the saw. The only way to find it will be to disassemble the saw and inspect the bearings. There will be quite a bit of tear down to replace the bearings. I think if it were my saw I would replace all of the bearings. If one went bad the others probably are not too far behind it. There are two armature bearings. They are part numbers #2610911928 and #2610911927. There are two more bearings on the blade shaft. They are part numbers #2610996949 and #2610997210. All of these parts are available from http://www.ereplacementparts.com.
We have run into the same problem several times with the Model #4000 tablesaws. We have always found the problem to be with the field. I would bet that a new field would solve the problem. The field is part #2610996867 and is available from http://www.ereplacementparts.com.
Good luck with your repair!
-Mark
Reply: Motor Running Opposite
BillNH
I have the same problem and am getting ready to check the motor. I don't see any parts listed for the start capacitor. Is this integrated with the field in this saw, i.e., does one have to buy the entire field even if the capacitor is bad?
When starting saw I notice a hesitation before power starts reaching normal operating speed. Could the soft start function have failed? Is that part of the on/off switch or is there a separate component that controls the soft start function that needs replacing?
I would suspect the problem to be the speed control. The problem is that there is really no way to test it other than to just install a new one. The speed control is part #2610997306 and it is available from http://www.ereplacementparts.com.
The saw can still get up to full speed but it rarely does because of a "loose" connection. There are no wires that are hanging loose or anything, but you need to jiggle the wire where it goes into the motor to make it go for a second or two. The connections into and out of the controller are good so I'm guessing it's the controller itself. Is there any way to determine that or do I just have to start ordering parts until the saw works?
If jiggling the wires makes the problem go away I think I would start with wiring. It looks like there are several crimped junctions in the wiring. I would suspect a bad connection with one of them.
I am unable to get my table to lock into place. The handle which operates the lock is putting up a lot of resistance. I have turned the saw over, cleaned it, blown out any saw dust, etc. and I still don't seem to be able to fix it. Any ideas as to what is going on?
This sounds to me like an adjustment issue. Item #118 on the parts diagram is the adjustment screw for the table clamp. I am guessing that it is currently adjusted too tight so the clamp can't lock.
My Bosch 4000 motor just bit the dust the saw is 2 1/2 years old and looks brand new. I hardly ever use it. I checked the switch and the brushes all is fine, but it was making a loud noise just before it started to run at half speed. I then shut it off but it never turned back on. Where do I get a new motor?
Sorry to hear about your saw. The motor is not sold as an assembly but you can get the parts you need to repair it. You will want to take the motor apart and verify what part(s) failed. My guess is that you will need a new Armature, part #2610996866, and the field, part #2610996867. You will also want to replace the armature bearings, part #2610911927 and #2610911928, and the motor brushes, part# 2610997207. Check the motor housings for any melted plastic. If you find melted pieces they will need to be replaced as well.
A loud noise is usually caused by bad bearings. However you will need to do a little investigating. There are bearings on both the arbor shaft and on the motor armature. You will need to first remove the armature so you can test the bearings on the armature independent from the ones on the arbor.
I have a Bosch 4000 T.S. and continually have problems with the fence setting up out of square and moving while trying to set a exact measurement. I was wondering if anyone knew of an aftermarket fence that will fit my saw. Is there anyone who owns this model and has had similar problems that maybe there is a fix for? Thanks for your help.
Clancy
Hi - just ordered field, control board and brushes. This will be the third time. First two were done under warrantee a couple years ago. I like the saw and stand and its cheaper than a new saw so am fixing one more time. On the other hand....was wondering if the field/board have been imrpoved so maybe...just maybe....it will last a little longer. I baby this thing by blowing out motor and keeping it on good power. Really a weak motor.
thanks
Hi,The small speed control board has been a problem for Bosch for 3 or 4 years. I'm not aware that Bosch has published a service bulletin in regards to it.I too have replaced a number of these circuit boards.A lot of these parts comes from China and their quality control seems to be up and down on stuff like this.Sorry I can't give you better information.
The motor on my table saw has started sporadically slow down then speed up. I noticed sparks inside the motor housing when this happens. Do you think its the armature, field or speed control switch?
I don't want to start replacing parts until I am sure.
firstly you can try replacing the brushes cause after a while when the brushes get short and they are not making proper contact wit the commutator sparking or arcing would occur.
then if that still dont work,possibility is u need a new armature
I am replacing a broken gear cover with a new part.I can not figure out how to remove the primary shaft from the old broken piece to install in new part.I see no visible clips or retainers.Does the nut on the shaft have to come off? If so how is the shaft secured to turn the nut?Is the nut left or right thread?Or does the bearing on the opposite side have to be pulled to enable the shaft to slide out?Anybody know?
[QUOTE=josephscal1;7965]I am replacing a broken gear cover with a new part.I can not figure out how to remove the primary shaft from the old broken piece to install in new part.I see no visible clips or retainers.Does the nut on the shaft have to come off? If so how is the shaft secured to turn the nut?Is the nut left or right thread?Or does the bearing on the opposite side have to be pulled to enable the shaft to slide out?Anybody know?"
The housing comes off after you take out the GUIDE PINS, They have 2 C-CLIPS each on the inside of the UNDER COVER. Then you have to remove the LEVER that sits on top of the Housing, There are two screws under the lever which will release your housing. I hope this is what you where asking. Good luck
I recently purchased a used Bosch 4000 10" table saw. The motor appears to have gotten wet. As a result the blade turns extremely slow and makes a very loud grinding noise. If anyone has any input as to which parts may need to be replaced I would greatly appreciate it.
[QUOTE=RichardGrzy;7626]I recently purchased a used Bosch 4000 10" table saw. The motor appears to have gotten wet. As a result the blade turns extremely slow and makes a very loud grinding noise. If anyone has any input as to which parts may need to be replaced I would greatly appreciate it.
Thanks,
Richard"
You might try replacing the brushes and you may have to take motor housing apart clean and the bushing and the armature use crokus cloth fine grit you can get at any hardware store in pluming part of the store the and put some white grease. I believe it is call lithium grease.
Reply: Bosch 4000 Table Saw Grinding
zekeroo
I had a similar problem with my bosch 4000. I took it apart and realized the rear bearing was corroded. I think it was from getting wet on jobsites. I replaced that and it works great now.
I thought that it would be easy to remember the wiring terminal connection configuration. I have the parts diagram, but it only shows two wires. When reassembling a couple days later, I started having doubts if the white from the switch is with the blue from the SC board and the black from the SC board is connected to the white of the field and the black from the switch is connected to the black of the field. A picture should have been taken. Since these saws have some much motor replacement trouble, can anyone confirm/straighten my wiring thoughts to the right connections. I found another model that had the three two wire connections and it made more sense.
We have a model #4000 in our shop right now. Here is how it is wired up...
Black cord to Blue controller
White cord to White field
Black field to Black controller
Black controller wire with connector to the other field connection.
I hope this helps!
-UtahAV
-Mark
Reply: Bosch 4000 Speed Control Wiring ...
RJWLOGIC
I greatly appreciate the detailed response. It now soft starts and rotates the correct direction. All is good for another round for this motor. Thank goodness it was only a rear bearing and housing. I replaced the speed control because that piece could not be tested like the armature and field, which both tested OK. I'll take the picture and or write it down next time.
Bosch table saws have two weak areas. The bearings they use and the design/ construction of the field. The most common problem is the bearing on the end of the armature. It tends to sieze up. "very" common problem with that saw. Good news/ bad news. Good news is a new bearing is about $10 and easy to replace ( with the correct tools). Bad news , if you've used it for any period of time with a siezed bearing you probally melted the plastic housing that the bearing sits in and that will probally have to be replaced also. (which is a bit of a pain in the ass repair .)
if the bearing feels good ( highly unlikely ) then the field has probally overheated and will need to be replaced, another common problem on that saw.
I recently had the tail bearing on the armature go bad. Because it had basically fried the seat where the bearing sits, I replaced the bearing, the rubber cup, the motor housing, and also got new brushes. When I finished and turned the saw on, it ran smoothly. I didn't use it right away but came back to it a few hours later to find that when I turned it on it quickly ramped up to warp speed. I immediately turned it off and came back to this forum. I read that either the speed control or the field (or both) would be the problem. I really can't see where something like the speed control could just "go bad" during the course of a few hours. Since I am rather new to this kind of repair, perhaps there is a kind soul out there to either help or put me out of my misery!
Hey dray;
First off..congrats on your initial repair.:) To the best of my knowledge the speed control is designed to keep the speed constant under load and to help with start up load..the saw can't really run any faster then it is designed because of the size of wire and the number of times it is wound to maintain the speed and load..so.. you still may have a field problem or maybe you brush's started to seat in causing the rpm's to increase but the saw really can't go any faster then it is designed to go..[if the speed control does have some issues it would be just a minor difference in the rpms and not a warp speed situation..Anyhoo, that's been my experience with this saw..
hope this helps..?
cmoorejack
Reply: Bosch Table Saw Model 4000
dray
Jack,
I finally got a chance to install a new field and- Voila! it seems to be OK! Of course I'm going to cross my fingers every time I turn it on (at least for a while). Thanks for some good advice!!
Don
Hello,
I bought a new grip for the fence on my Bosch 4000 as the old one was missing when I bought it (used) Can somebody tell me the best way to remove the pin that held the old one in place? Thanks!
Hey unclejimmy,
You can drive out the pin with a pin punch and a hammer [matched to the pin size] knock out to one side and there ya go..:)
you may need to support the assembly with a deep well socket or something close to aid in the removal [so it will have something solid to rest against as you drive the pin]
hope this is helpful..?
cmoorejack
My saw started grinding and sparking in the motor today. I was going to pull the motor off, but could not figure out how:mad:
Can someone tell me the best way to pull the motor off so that I can maybe repair it. I could not figure out if you had to take the saw off the stand or take all the components that raise the blade up or down off as well.
I was hoping that all you had to do was take the blade off and take the four screws off of the motor and it would slide out:). that didn't work for me.
You need to take the saw off of the stand. Then turn the saw upside down. release the bevel lever. tilt the saw on a 45 degree angle. Take the brush caps out and the brushes. There are four screws that hold the motor housing on. Take them out and the motor housing and field should slide off. Sounds like a bad bearing. let me know what you find.:eek:
My saw siezed up on me the other day after years of pretty good abuse. I took out what appear to be the brushes (looked alright), and cleaned up everything with an air compressor. Too much saw dust, I should have kept it cleaner! I removed the blade, and cleaned up everything real good thinking I was about to tear it apart and I wanted everything as clean as possible to start. Noticed I had an outlet within reach of the saw cord and figured whats the harm, right? The saw actually started up perfectly. I turned it on and off numerous times, multiple days, and it kept turning on. Today, I went and got a new blade for it and after installing the blade, the motor got stuck again. When I turn on the switch, the blade won't budge, and the motor makes a humming noise that sounds so bad, I immediatly shut off the saw. I've read of this saw having a problamatic Field, but I'm not sure if it isn't a bearing or something else since it appears to be stuck. I removed the blade again and without the blade on, the motor seems to run fine. I'm sure I'll see more when I take it apart in a day or so. Anyone with similar experiences? Any help or insight would be greatly appreciated. Thanks,
Hey hoof123,
There are several posts here about this problem..it seems most likely that the field has failed and reversed polarity..you may also have a problem with the speed control..[and hopefully the armature is ok..]..but the field is the first suspect..
parts available at eReplacementparts.com : Power Tool Parts and Tool Repair
hope this helps..:)
cmoorejack
Hey craftyf1,
The best method is to use a bearing puller..I use a otc 1020 or a 1021...the price range is anywhere from $35.00 to $55.00..you may be able to use a wheel or gear puller avail at any auto parts store..[ereplacementparts.com has the otc 1021 avail ] Old school method is to use two large flat blade screwdrivers to pry off the bearing..the trick is to secure the armature as best you can in a vise without damaging it and using the blades behind the bearing to pry out without damaging it..:) I prefer the puller method..However, there may be some other suggestions out there..
Hope this helps?
cmoorejack
I see I am not the only homeowner to drop $500+ on a "nice" bosch table saw only to have it crap out after a couple of uses. I opted for the bosch 4000 table saw with the portable stand over the $100 "cheap" ryobi because I too like nice tools and figured it would be the last table saw I would need to buy. I had it for a couple of months and the third time I went to use it, the motor started to grind and arc. I pulled out the brushes and they were chipped so I bought new brushes but it still had grinding sound. Took out the brushes again and looked at the rotor with a flashlight and it appears as if the rotor has chips in it. I was very unhappy and completly unimpressed with Bosch, especially after seeing the troubles that many others are having also. If Bosch would like to charge top dollar maybe they should have a top product to go with it. I needed a table saw so I bought the ryobi which has preformed flawlessly out of the box for the last year now. I finally have some time to try to fix my "nice" $500+ bosch table saw and would almost prefer to spend the next $200 on airmailing it back to bosch instead of on a new armature, but they probably would not drop it from 30,000' to get it back to them as I would prefer so I'm looking for the best way to get the most dependable fix for it. Is there a higher quality motor that can replace the exsisting one? I would hate to replace the armature only to later need to replace the field only later to replace something else. I thought about putting the dependable ryobi motor in it but it is a little different size.
thanks, Buddy
Hey guys,
New here. Been buying parts but never used the Forum, so here goes,
Customer called and said that his Bosch 4000 started tripping his breakers in the shop and the motor is struggling also running backwards?
I took the motor apart to find the armiture is good along with the brushes and the bearings. The windings look a little discolored but not fried. So why is the motor running backwards all of a sudden? I checked the switch then plugged the motor direct into the current(20amp)
by-passing the switch and also reversed the wiring on the cord, same thing....it never tripped my breaker but it does run slow and backwards. What do I try next?
Thanx for your help!
Mike
Hey Mike,
Not a quick fix on this one..The polarity has reversed itself..If the armature checks out ok with a growler test..I would suspect the speed control and the field are bad or shorted..I would replace both just to be safe and that should take care of it..[I haven't come across this problem before ,but you only have 3 components..armature ,field,speed control..the switch and cord just provide power to the tool..you can do an ohm test between the field coil windings to see if they match up close..but if you have discoloration there is probably some heat damage and the windings have shorted to each other..:(
Hope this helps?:)
Craig
Reply: Bosch 4000 Table Saw
ifix2ls
Thanx Craig,
Ill give that a try.
mike
Reply: Bosch 4000 Table Saw
Dale
The field is the weak link on this tool. Hope your armature is ok. ;)
Reply: Bosch 4000 Table Saw
ifix2ls
Ill look at that also Dale
Thanx,
mike
Reply: Bosch 4000 Table Saw
bummer
I bought a bosch 4000 about a year and a half ago. I used it for one light job and let it sit for about a week. I tried to used it again to finish the job, but it bogged down and ran in reverse. I am very upset. It's brand new. I have used many bosch table saws at work (treating them much rougher than this one at times) and have never had this problem. I am convinced it is a factory defect. Any one else heard of this problem.
Also, if it is known what is wrong now, can I please get a little help.
Thank you
Reply: Bosch 4000 Table Saw
Dale
Yup it's your field. should still be under warranty. Hope this helps. IF you need me to I can find your closest service center.
Reply: Bosch 4000 Table Saw
MarkB
Wow, what a telling thread. I guess I'm not alone with my Bosch 4000 saw problem.
My Bosch 4000 hasn't run backwards but here's my sequence of events:
Normal operation for about a year or so (light homeowner use, no abuse/overload, ever).
Then one day:
Saw running, no load (getting ready to cut some moulding).
Suddenly speeds up like 2X. Immediately shut it off.
Tested it a few times to see what was up. Goes immediately from a dead stop to overspeed, and has an "electronic" smell.
Figured the speed control went TU. Ordered another one and replaced it.
Overspeed condition now cured, but it doesn't sound the same. Draws more current than normal (flourescent lights on the same circuit flicker, cord gets warm).
Serious arcs around the commutator when it runs, nearly a continuous blue flame around it's circumference.
Took the motor apart. All looks fine- no zorch marks, signs of burning, bubbling or any issues that would indicate a failure or overload.
Brushes showing signs related to the arcing but are otherwise in good shape. Brush holders and springs seem fine.
Had it tested at a commercial motor repair shop. Armature tested both on a growler and a 3 phase tester for impedance anomalies on all windings. No trouble found. Was told the
field tested "OK" but after reading this thread I'm beginning to wonder.
Since we are only talking about 3 active components here worth over half the value of the saw, and one of those being new (speed control) I'd hate to just shotgun it with a new
field and armature.
Is there a better test to perform, even if I have to mail it somewhere to do so? Or any opinion of what it might be or should try first?
Figured I'd buy a nice saw and have it for years. Now I'm faced with a repair cost that exceeds what I can get an entire cheap chinese saw for...
Mark B.
Albuquerque, NM
Reply: Bosch 4000 Table Saw
Dale
If your Armature test's good. I would spend the money on the Field. $ 57.00 its worth that. if you don't mind twisting a wrench. 90% of the time its the field.:eek:
Based on the info in this thread I took a chance and ordered a new field and installed it last weekend. The saw now works like a charm. I let it run for a while to break in the brushes a bit and make sure nothing overheated, and it all seemed fine. Other than crossing my fingers every time I turned it on, it performed perfectly all weekend cutting hundreds of linear feet of 1" plank.
Out of curiosity I unwound the old field to see if I could find anything obvious wrong with it and couldn't. No copper snot, zorch marks or signs of overheating or abrasion anywhere that I could see. That's not to say it couldn't have been shorted at some tiny spot that I missed (~150 feet of #18), but it's not like it suffered some major and obvious trauma or abuse.
So thanks guys, and hopefully this will help the next guy with a Bosch saw that mysteriously fails without warning.
I have a bosch table saw that I am having problems fixing...
Several months ago the bearings went bad so I replaced them along with the brushes. Recently it has started to run at higher RPM and the brushes are arc heavily. I replaced the brushes, armature, speed control and bearings. It is still running at higher RPM and the new brushes are arcing again. The only thing I have not replaced is the field.
Any suggestions???:confused:
Have used and enjoyed my Bosch (Model 4000) portable table saw for 5 years where it has received moderate use.
I just started a new project and it now is making a "grinding" noise with a burning electrical smell. I checked the brushes and they look fine. When you rotate the blade by hand it does seem to feel like it may be bearings? I'm pretty capable in repairing things but am asking a logical troubleshooting process on taking it apart so I then can order the correct replacement parts.
Hey Tom,
Usually a grinding noise is gear related..however i have worked on a few of these and most likely the rear armature bearing has locked up and the whole bearing is trying to turn in the plastic housing [the bearing also sits in a little rubber cup and that is probably melting and causing that burning smell] of course as soon as you start taking it apart you should be able to discover the problem..:)
hope this helps...
Craig
Reply: Help W/Bosch Table Saw
Doggorloader
Succeeded in getting the motor assemble off the guide rails and out of the saw. removed the screws holding the motor casing together, removed the brushes, and now I can't seem to get any further. It seems loose enough to come apart but I don't want to force it.
Before I took it apart I cut one last required piece for a project and the motor had such a tough time starting it actually spun the blade nut loose. That was it, done.
Now, by looking at the parts drawing, it definetely seems as though bearings are bad, but, there is also a gear in the front of the motor. Is that a possibility that it's stripped as well?
Once the case is apart (if I get that far) are the bearings pressed into the case? Am I getting to the point where I send the motor in to Bosch or am I still on the right track to ordering parts to fix it myself?
Thanks,
Tom
Reply: Help W/Bosch Table Saw
cmoorejack
Hey Tom,
If you haven't been able to remove the housing case..this may be one for bosch..[you would also need a special puller to remove the bearings from the armature]..it sounds like the motor has more damage then a simple repair..:(
[ereplacementparts.com also doe's repairs]
hope this helps...
Craig
Reply: Help W/Bosch Table Saw
Philp
Hello,i have worked on alot of these, and dewalts portable saws,One thing that i found is very common is that they tend to get hot enough to melt the plastic around the field which makes it hard to get the armiture out. Double check that you`ve gotten all the fastners out of the case and using a flat screwdriver pry (gently) on the top the armiture usually they`ll pop out so you`ll be able to see both bearings and be able to inspect both the field and the armiture. I hope this helps in this case,good luck
The motor on my table saw has started sporadically slow down then speed up. I noticed sparks inside the motor housing when this happens. Do you think its the armature, field or speed control switch?
I don't want to start replacing parts until I am sure.
The motor on my 4000 just burned out after only a couple of years of occasional use. A motor repair specialist suggested I use his dumpster to get rid of it, because there was no way that I could justify the repair costs compared to a new Rigid on sale at $399.00 with a life time warranty.
Burned out motors are a common problem with table saws, often because people push material through the saw too quickly. It costs around $200 to replace the armature and field in the Bosch 4000 saw, or about half the price of a new tool. Definitely expensive, but it could be a worthwhile repair.
Reply: Bosch - 4000 Defective Motor
jim
A Ridgid saw does not really have a life time warranty. The warranty only covers defects in workmanship or material.
We have several of these in the company. The saw is well designed with lots of nice features however the motors don't last. Sometimes replacing the tail bearing on-saw will fix it but when the whole motor needs to go out for rebuild it is a pain to remove. I would like to have a spare motor to swap into ailing saws to get them back on line in one operation but Bosch refuses to sell me one. The need to lock both the fence lock and the extended fence lock has caused a few dangerous situations when the one under the table was forgotten.
I have had my Bosch 4000 for a long time. It is a great saw in every way. Strait, true cuts every time. It was a little on the expensive side for a table saw compared to some of the other brands, but like they always say: you get what you pay for.
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