DeWalt drill woes

[Steve]

I have a dewalt cordless combi drill, about 5 years old now. Its had a few knocks (the case has come apart slightly but still sturdy). I only use it for occasional DIY use now, but whenever I come to use it there is a smell of burning and smoke/dust comes flying out of the motor. I now have to run it for 20 seconds at full throttle outside before I can do any work with it. I'm guessing at some point dust or debris has got into the motor.

I don't want to get rid - it was a long term investment (having seen my dad get through B&Ds like I get through underwear). Is there a way to take the motor apart and clean it? Would this need any special equipment? Could I do it myself?

 

[big-all]

model number would help

 

[Steve]

DC988. Sorry.

 

[big-all]

i have that one
i suspect the brushes need cleaning/changing but cant remember if they are replaceable will have a look later

 

[Steve]

It's a nice drill. But even at half price was £150 and so a big outlay for diy. Wanted a drill to last a bit longer than 5 years for that price.

 

[EddieM]

Yes, the brushes are replaceable on that model, assuming of course that is the problem.

I have never owned that model but I do seem to remember dewalt having quite a dip in quality a few years back, seem to have recovered but I definitely recall looking at some of their stuff a while back and thinking it looked a bit carp.

 

[big-all]

was it stored in a cold damp environment

 

[Steve]

was it stored in a cold damp environment

it might have been. . .

Why?

 

[big-all]

can cause the brushes to glaze over
remove the brushes and clean with very fine emery paper or a very very fine needle file
do not touch the commutator with anything more abrasive than metal polish

 

[Steve]

Just seen a video on you tube of a man cleaning his brushes and the back of the motor in turps with a brush. Is this wise? Search YouTube "smoking dewalt drill". Look at part 2. He seems to have had good results and it looks so easy. Any advice on this?

 

[big-all]

if its just dirty then fine
i used to use lighter fuel on 12v triang and hornby model railway locomotives and worked great but they where open around the commutator so minimum lighter fuel was used
turps would work but its less refined
whatever you use it must be fully removed/evaporated before you run the motor

if the turps doesnt work then do the de-glazing as i suggested
other causes can be overheating springs through arcing going soft so reduced contact

do not use a file on the commutator ever without knowing what your doing and he doesnt
and never use a vice in that fashion on a motor

 

[Steve]

Wow its been 4 months since I started this! I finally got around to opening up the drill and removing the brushes.

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• Steve
• 12 Apr 2015
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• Steve
• 12 Apr 2015
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• Steve
• 12 Apr 2015
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• Steve
• 12 Apr 2015
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• Steve
• 12 Apr 2015
• 1

Any recommendations? Is it worth replacing the brushes or should I just give them a clean in spirit? I've also seen comments on youtube videos that I should scrape out the grooves in the commutator as carbon deposits there could cause short circuiting between the brushes and loss in power (and the resulting sparks as it spins).

Any ideas?

 

[Burnerman]

There's been some overheating there.....by all means clean out the commutator segments with a Stanley blade and replace the brushes and holders if you wish, but I don't reckon that drill has long to go.
Its always a good move to blast out any air passages with compressed air, if possible.
John

 

[Steve]

Could the overheating have been caused by the build up of carbon though? Or is it the other way around? Have I been pushing it too hard at one point and its caused the carbon to deposit? The smoking/sparking started IIRC when I was drilling holes in the decking for 10 decking lights with a 16mm spade bit. Could it have happened when I used it in damp conditions?

I don't have access to compressed air sadly but I will remove the motor and brush/blow out all the holes in the motor and casing.

 

[big-all]

i would definatly clean with lighter fluid and rub the brushes to deglaze the surface as you have nothing to loose