Milwaukee Hammer Drill is smoking

[Jennifer]

Hello,

I have an old (23-25 years) Milwaukee 1/2" Magnum Hammer Drill, model 5370-1. I haven't used it in years, but got it out the other day and noticed it seemed to have oil on the body (unknown origin, but not spilled on the drill for sure). I cleaned that up and proceeded to use the drill to mix a fairly liquid unmodified tile mortar at a slow speed. The drill started smoking like crazy.

(I know that is probably not the best use of the drill, but my cordless drills don't work well enough to mix for 5 min, slake, then mix again for another 3, etc. It does not seem to smoke as much out of the mortar and run at a faster speed).

Anyway, my boyfriend immediately says "it's a piece of junk, throw it out", (which is his usual response for any of my tools that might need maintenance). I'm not of that mindset and would like any ideas on what might be going on, if I can do something to save the drill, or if it is hopeless?

Any advice would be greatly appreciated as I'm more familiar with using tools than fixing them.

 

[Ben Buck]

Are you using a thin extension cord with it ?

Say 16 gauge , if so get a 12 gauge one and see if that helps.

A 5370-1 is a heavy use drill , If I remember correctly.

YMMV

 

[bob15]

If you just plug it in now and pull the trigger on the drill, will it smoke? Is it possible you were cooking off whatever was spilled on it?

What did the smoke smell like? Burnt electrical?

 

[seber]

Is it likely that oil got into the drill from the outside? If so, the heat from running and the arc at the brushes will cause smoke. If that is the problem, you can take it apart and clean it with alcohol or acetone. On the other hand if when you separate the halves you find burned coils, it is done.

 

[M635_Guy]

I can't contribute much other than to say you should tell your boyfriend that he should hope you won't have the same mentality about him...

 

[dutchgray]

The oil if not spilt on it likely leaked out the grease that would have been in the drill its pretty common to see on old little used tools, with gears in them, if it got on the brushes or commentator it would turn to smoke immediately, on the windings it would take a little time to smoke, mixing tile glue at slow speed is heavy use and will load it pretty well so the drill internals will get pretty hot quickly.
If it still runs fine it probably is, you might want to open it up and change the grease in the gearbox, inspect the motor windings where you can, if it looks burnt or heat discoloured copper its probably not going to last long.

 

[woody 73]

(one) Dump the boyfriend.
( Two) oil ran from the grease inside the drill , open it up and put in new grease.
(Three) find a new boyfriend that loves you and tools.
( Four) Welcome to the GJ.

Woody

 

[SGKent]

or the windings smoked and the boyfriend is trying to avoid the crispy critter syndrome. What an opportunity to try it in a wall socket after it cools down to see if it is still good, and if not find a another used one or buy a new one.

 

[neophyte]

or the windings smoked and the boyfriend is trying to avoid the crispy critter syndrome. What an opportunity to try it in a wall socket after it cools down to see if it is still good, and if not find a another used one or buy a new one.

That drill model is double insulated, sp there is little chance of electrocution from the windings shorting out if they do.

 

[neophyte]

That particular Milwaukee drill model id from the Super Magnum series, which were one of the go to drills for a heavy duty model that could withstand abuse.
It is in no way a piece of junk, and should essentially last for decades of use.
As others have mentioned, if the drill sat for a while, the oil in the grease likely separated from the thickeners in the grease, and leaked into the motor, and then started smoking when the motor windings got hot.
Even if the motor or field burned out, both parts are still available, and that drill will have been better made then most corded drills still available nowadays, including the newer Milwaukee versions, which will now be made in China.
Mixing Mud might be better done with one of the heavier dity, slower, plumbers drills though.

Those drills really were solidly built, and I think the only complaints tended to be with the gammer action not being quite as good as some other drills, and with the brush replacement system, which I think annoyed some people.

 

[redragoon]

I've known drills to smoke when they get oil on the motor. Had one guy drop a DeWalt into a bucket of oil. Smoked for a while, but went away as the oil dried/cleared. Better to refurbish/clean than buy a new one with decades of cost savings added in.

 

[engineer2]

With the drill being that old, it's time to open it up for inspection and repair. Not hard to do, just take the case screws out and start disassembling it. Take pictures as you go.

If the windings or amature smell burned or look black, you have to decide if it's worth fixing. Replace the old grease, check the length of the brushes. Inspect the power cord. Pay attention to the order of parts for the gearbox.
When reassembling, pay attention to internal wire routing, sometimes getting it to stay put when reassembling the case halves.

BTW newer cordless drills have no problem mixing mud, but you have to buy a heavy-duty model, not the homeowner model. The heavy duty models generally have a metal gearbox instead of plastic. They usually come with a side-handle which you will need to hang onto it when mixing mud. These newer models have electronic controls to stop the motor if it gets too hot. The Makita XPH07 is one example. I use it for mixing mud and concrete in a 5-gallon bucket with no problems. Milwaukee, DeWalt, and others make similar models.

 

[Dingleburry]

Wrong tool for the application.
Not being a ****, im guilty of it many times a week.
Just a few things you gotta look out for/understand.
Mixing takes alot of torque, also depending on the diameter and. Agressiveness of your mixing blade, and viscosity etc. Plus the length of run time to mix, vs drilling a hole. Over torqued for too long.
You can run motors over their rated amps but their gonna heat up past rated temps. You can increase cooling, run intermittently, lower the load (torque) etc. But you must dissipate more heat then your generating, while also keeping it under max rated temps. My guess is it was the resin on the windings.
Ive made 3 milwaukee drills smoke in the past. A hole hawg, which still runs 5 years later, only used a couple times a year. An m18 compact, was its 3rd use, that one died on the spot. And an m18 full size, smoking and sizzling, ran prefect for another 4 years.
I would think overloading it like that could also overheat heat the gearbox aswell. Not just the motor. But my guess is windings.

TLDR
If it still runs and drills fine without heating up (motor and gearbox) i wouldnt worry about it.
If it still does with its designed use then i would investigate further.
Like finding out whats actually heating up, and what the smoke smells like..


Just some thoughts.