How to Remove a Stuck Drill Chuck
Broken gearboxes and sticky chuck screws can make removing a drill chuck difficult. This article explains the tricks you need to overcome these common repair setbacks.
Drilling, Fastening, and Hammering Power Tools
This article lists the major categories of drilling, fastening, and hammering tools, and explains the basic applications, types, and features of each.
I took apart a Dewalt DW987 18V Drill to replace the outer shell.
As it came apart, the transmission fell out and some gears fell out.
I'm looking for diagrams or videos showing how to put the transmission back together.
Specifically, I'm not sure how the pin that connects to the torque setting connects to the wavy metal ring.
Hi Drew987,
I'm sorry but I don't know of any pictures or video that shows how to put the transmission back together.I've had a number of these transmission come into our shop and its always a trick to try to get them back together as they have made so many different types and changes on existing models .You might try utube.I wish I could give you better help.Good luck.
Tinker
I'm having trouble determining which part is bad in my DW987. The clutch does seem to grab fine ~if~ the chuck turns. The motor turns but the chuck doesn't. It will seem to work fairly well if I point the drill down or tap the chuck face on the countertop. But after a bit it will stop spinning again.
I'm leaning towards the transmission. Any help/thoughts would be great!
Hi Waferboy, The part you need is Transmission Part Number: 397892-05SV.But check you date code as this might be warranty as Dewalt had a lot of problems with this transmission unit.Hope that helps.
Tinker
I recently had to take my Dewalt DW980 cordless drill apart to clean, and when I went to put it back together I ended up with several extra parts which I can't figure out where they go. When the transmission was taken out all the gears and whatnot came out, and once I put it back together there were still these 5 little metal pins left as well as a little metal piece with one pin on each side and a metal piece in the center. I've looked all over, but just don't see anywhere where these pieces could possibly go or what they're even called to look them up.
If you could post an image of the extra parts you have left over, it might be easier to identify them and then let you know where they go.
-WJA
Reply: How To Reassemble The Transmissi...
JTS
Here's an image of the pieces.
link removed
Reply: How To Reassemble The Transmissi...
JTS
For some reason the image didn't post properly the first time, but I've fixed it. So does anyone know where these parts could go???
Reply: How To Reassemble The Transmissi...
WJA
Hello JTS,
Well I thought that once we saw the parts that you are having a issue with, it would be an easy fix. But talking to a tech, the last time he had a transmission fall apart on him (2 years ago). He had to get another one and carefully take it apart to see how it all went back together. At this point his memory fails him on the parts in question. Hopefully someone out there will see this and be able to help you out. We'll keep trying though.
-WJA
Reply: How To Reassemble The Transmissi...
Tinkerdave
Hi JTS, The large bottom pin is the detent pin that goes behind the detent spring.This keeps pressure on the torque adjustment collar. the other parts are cam followers that are position on the front of the transmission .When you pulled the transmission fron the gear case housing the shaft from the gear case housing that went into the transmission went into a small collar.Those rollers go round that collar.Its hard to explain without a exploded view of the transmission.Hope that helps a little.
It sounds like the transmission has failed and will need to be replaced. It is part #397892-05. We have an article and video available that should help.
I overheated my Dewalt 987 drill using a holesaw. For the next week or so, when pulling the trigger it would be intermittent, but it would work. After about 2 weeks while using the drill the battery started smoking and became extremely hot. Assumed the problem is with the switch. Put in an old battery pack and burned it up too. Before I buy a new switch, any info would be helpful, I don't want to burn up another battery.
Sparking usually indicates at least bad brushes, but often means you have a bad motor as well. This is usually due to overloading the drill. Thankfully it's an easy fix. You can try replacing just the brushes first to see if this fixes the problem, but the surer fix is to replace the motor which comes with the brushes anyway.
You can replace the trigger, but on your DW987 drill it's part of the switch (part #152274-19). The switch is usually the problem if you lose variable speed, and it will fix that sticking problem as well.
Hi Sonny. The torx screw inside the DW987 chuck is reverse-thread, meaning that you'll have to turn it clockwise to remove it. That might be why you're breaking torx drivers. eReplacementParts has a helpful article and video about removing drill chucks here:
when i plug the battery in the drill and start using it i notice that the battery got really hot, i unpluged it quickly and notice smoke coming from inside the handle where the battery plugs in. the battery work fine in my other drill. any thoughs? thanks
Jay-- Are you sure that both drills are rated for the same voltage? One of your drills could have been mis labeled for the wrong voltage. This is a long shot but you might want to double check.
After reading some of the posts in here I think it is motor time for my DW987, it has plenty of brushs left but smoke and smells bad when running also alot of sparking. I could probably take the time and sand and clear everything up in there but for $40 I might just change the motor.
How hard is it to get the motor assy out and back in?? I could not find and infor in here on actually removing and re-installing the motor.
Hi Reboot. Yeah, sounds like a motor problem to me too, since you've got a burning smell along with the arcing. Changing motors in these drills is pretty straightforward. You'll need to open the drill housing with a torx driver, and the motor will come right out. You can find the DW987 motor here.
Hi again everyone! After the success of my last repair Im thinking about repairing my cordless dewalt drill! I have repacked my own dewalt batteries numerous times now. Im very sure I do it correctly, all the voltages are what they should be when im done and everything checks out fine. The problem Is I don't seem to get the same amount of life out of my drill (and some other dewalt tools for that matter). The AH rating of the battery cells I use is greater than the stock ones, so theoretically I should get better life than those, but this dosent seem to be the case. I'm wondering If this is because my drill is simply old and the motor is somehow burning extra juice that it dident in the earlier years of its life. I do notice a very strong "electrical burning" order when I run the drill coming from the motor vents. Someone else even noticed it when I was using the drill around them.
Do you think its possible that replacing the motor for my cordless drill will help extend the battery life of it? Or is it most likely the aftermarket battery cells I am using?
Hey Chupa
Congrats on your success!
With your problem now..it could be the aftermarket batteries and or the charger may be having some issues [shutting down before the batteries are fully charged]
Also any drag on the tool from worn out components will always drain down the battery prematurely ..[even using the drill in high or low effects the drain] dull drill bits, heavy link removed it left-handed..that sort of things.;)
replacing the motor is highly recommended if you have had heavy use or if there is a burning smell [not a ozone smell]
Geter done...!
hope this helps?
cmoorejack
I have a DW987K-2 drill that i pulled apart due to a bad motor....while i was backing out the transmission all the gears fell out as well as this "pin" which was located along the outside edge of the Gearcase housing which was also spring loaded. Does anyone know which way this pin goes back in? there are a couple of different ways it could go back in.
I have a similar problem - dropped my drill into the ocean - got it back quickly - battery was fried, but drill is now fine, motor works great. I took transmission apart to wash and clean and now have a part left over - flat metal plate (anodized blue) and don't know exactly where it goes. Although I have it basically together, it's outside the plastic housing it lives in and not sure how, or in what order to get it back inside. Is there anyplace I can get an exploded parts diagram? Dewalt service guys here are useless. Laughed when i asked how to get it back together. They just buy new transmissions.
Reply: Dewalt DW987K-2 Problem
cmoorejack
Hey guys,
You can stay with the trial an error but it is really better in the long run just to replace..:)
Here are some previous posts..
http://forums.ereplacementparts.com/power-tool-repair/728-dewalt-dc987-transmission.html
I have been able to reassemble [for the challenge..!] but better safe than sorry with just replacing...:D
I have a Dewalt DW987 18v drill that will burn up the battery after a couple seconds of bing used. The battery smokes gets hot and cant use it again. I dont know what the problem is. I do know it is not the battery because I tryed a new one. Any ideas
My first guess would be that it's shorting out the battery, or making it draw excessive current.
Does this happen as just as soon as you plug the battery in, or does it only when you pull the trigger? Does the motor even turn?
Reply: Dewalt DW987 Burns Up Batteries
ziamerc
It happens when I pull the trigger and the chuck will turn like normal.
Reply: Dewalt DW987 Burns Up Batteries
Dongle
Take it apart and disconnect the leads from the motor. In the DC987 they should be crimped connectors that just slide off the motor terminals. Pull the trigger and see if it still causes the problem. If it still does, replace the switch, if it's not then it's probably the motor. It could be both too. It's possible that high short circuit currents could have damaged the switch by now too. Inspect all connections and make sure the connectors are touching anything metal that they could be shorting against.
On the other hand, try taking it to a DeWalt service center. Chances are it's damaged your battery pack if it smoked and if warranties are still applicable they should fix your drill and replace the pack.
Hope this helps.
Reply: Dewalt DW987 Burns Up Batteries
tripletdaduk
[QUOTE=ziamerc;2965]It happens when I pull the trigger and the chuck will turn like normal."
hi,this has been a common problem in the uk,there has been faulty switches,youll need to replace the switch,but unfortunatlley a lot of the time it kills the battery as well !!
Hi
i Have a problem with my DW987, it seems like the clutch is slipping.
it dosent matter in what gear or torq setting i have it just keep slipping and im not sure what part that is worn out, i have made several reapirs on my gun but this one i have no clue so if anyone knows what part it is i will be forever greatful.
Hey Anders,
most likely it is the transmission slipping and not the actual clutch..or at least it is 90% of the time..! Part # is 397892-05...you can purchase from Ereplacementparts.com!!
Hope this has been helpful..
Craig
Geneva Tool Repair
I'm new to this site and hope I can get some great help from you! I recently replaced the trigger on my drill. When I took it apart I was careful to put it back the same way. However, The drill is kickin my butt! Everything is back togetherbut.....it is about a 1/4inch from the last 4screws going in. I must have something not lined up. I've started over about 10 times now and keep ending up...1/4 inch off! Is there a diagram or something I can refer to? Good thing I have a lot of hair! I'm starting to pull it out!.... Help! Teres. :)
Hey wow2awsum,
UGH! you probably disturbed the alignment between the motor and transmission..make sure everything fits into the one half ..the motor..switch..transmission +...before you reassemble..the motor has a plastic sleeve that has to fit just right into the housing..check for gaps..try kinda wiggling slightly [the components not you..hee..hee] until they fit..then put the other half of the housing on and then the front chuck assy..be patient and eventually you'll get it and then you will be able to brag to your friends of your accomplishment..!
man..i need some more coffee..
Hope this is helpful..good luck..
Craig
Hi my sink stopped up! so i got the plunger out got the clog past one drain, so the water back up too the work shop sink were i had laid my drill! it was under water a foot deep. so i took it a part and laid it on the shelf after 4 days in the garage , i put it back together. to my surprise it worked perfectly! also the garage its very hot lol..
I've liked having my DW987 around the house. This is definitely an industrial grade cordless drill, and it's probably more drill than I actually need for household maintenance. It's nice to have the power on tap though. I probably only really taxed it once, when I needed to open some stubborn coconuts. After getting frustrated trying to crack them open (they're hard!), I stuck a 1" hole saw in my DW987 and drilled right on through. The drill had to work a little, but I was impressed that a cordless drill could run a hole saw like that. My only real gripe is that the XRP 18 volt battery is a heavy item and it makes the drill too hefty. I will probably opt for a 12 volt next time around.
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