Good tool - broken - any ideas

[streetglider]

Covid 19 has me stuck at home. I have a Skil power wrench that I have had for many years and really like. It wasn't working so I thought I would take a chance on fixing it. I originally thought the batteries had worn out and was going in that direction. Now, I am wondering if it is the switch? I measured the voltage of the 3.6 batteries and each one was at 3.6. I measured them together
and they were the required 7.2 needed. I started to play with the switch SS-10 Microswitch) and saw that generally it would start the wrench but stop after a few seconds. However, there were times it would run for quite a while but it was inconsistent.
So, what's your guess, the batteries or the switch? I added a pic but since I am just guessing at all this, I may be way off. I had to research how to use a multimeter!!!

 

[MJO]

Bypass the switch and you'll know if it's the batteries, the switch or the motor.

 

[RTM]

My clone failed on the switch not making contact. If you can get it apart, and polish the switch contacts, it may help.

 

[SGKent]

measure the batteries again with the switch on. Usually by the time one gets done dinking with tools like that it costs more to try to fix it than it is worth. I had one similar to that and it died the same kind of death. It could be the motor too.

 

[streetglider]

I never considered the motor. I am going to measure the batteries with the switch on and see. Then I will try and bypass it. I know it's probably not worth it but this was a tool we used a lot. It's a 1/4 in drive and small enough to get into some tight spots.

 

[tym]

Also measure the voltage of the batteries under load (e.g. motor running with switch bypassed). Bad batteries batteries may read proper voltage open-circuit with no load, but then sag to an unacceptably low voltage under load.

 

[frankthezapper]

But the virus has you stuck at home, so something as unproductive as fixing this won't be wasted! And you have learned how to use a multimeter!!

 

[dogdog]

probe for voltage at the motor terminal. and see if you get a voltage reading with the switch on... maybe?

you really only have 3 components on that troubleshooting... invent any trouble shooting steps as you like, just make sure you isolate and test each electrical components

the motor
the switch
the battery (pack)

the wiring... (maybe if you consider that a component)

 

[bwringer]

I had one of these guys that did the same thing, and the failure was the electronic control board. This is not a tool that just has a simple trigger and reverse switch.

Nothing to be done about that aside from a respectful recycling ceremony... good night, sweet prince.

 

[streetglider]

I checked the batteries and they showed 7.1 for the few seconds when the switch was pressed and the motor working. I wasn't able to figure out how to bypass the switch in the circuit board due to limited intellectual ability. I am okay mechanically but electronic issues frustrate me.

I appreciate all your replies.

 

[MoonRise]

If the batteries have proper voltage under "load" conditions, then the problem is not the batteries.

(some types of batteries can show an OK voltage reading with no load on them, but will drop the voltage too low to do anything once a load is put on them.)

To bypass the switch, just get a jumper wire and connect that wire to let the current to go through the wire and not even go through the switch). If the unit works with the jumper wire switch bypass, then the switch is the most likely problem.

How to fix the switch depends on if you can 'rebuild' or clean up the switch, or replace the switch with a 'new' switch (same or different one).

And the problem still could be the electronic control board, no matter what else is right or wrong in the other parts (batteries, switch, motor, wires).

 

[streetglider]

I thought I would give an update on this since so many people were good enough to try and assist me. The tool is working as of today. I was able to determine the switch was not working right unless it was re-positioned very slightly. Not sure why (contacts?) but when I did that it ran okay. The batteries were not holding a charge for long so I changed them too. So far so good. Thanks.