Noob question about worn brushes (sawzall)

[rippledabs]

I never replaced a brush before, so I'm pretty clueless right now.

The brushes on my sawzall 2621 throws out all kind of sparks, then the sawzall itself just dies. I took it apart, and this is what I found.

Are my brushes worn? Did Milwaukee designed it so that the brush wire prevents the brush from wearing down too far? Can I replace the brushes? Everything looks to be hard soldered in. If so, where is the best place to buy replacement?

edit: I found a part number 22-18-0082 for the set, but no one online seems to stock it.

 

[tym]

I think the brush is broken? What's under the spring?

 

[rippledabs]

I think the brush is broken? What's under the spring?

Nothing, The spring goes on top of the brush. I just place the spring back in the hole after I took the brush off so I don't lose it.

 

[gungatim]

is that an older model? all the ones I have done the wire unclips from the holder and the brush is in the holder. heres a youtube vid

wonder if someone broke the holder and soldered a different brush in it's place maybe?

 

[LB-1911]

I never replaced a brush before, so I'm pretty clueless right now.

The brushes on my sawzall 2621 throws out all kind of sparks, then the sawzall itself just dies. I took it apart, and this is what I found.

Are my brushes worn? Did Milwaukee designed it so that the brush wire prevents the brush from wearing down too far? Can I replace the brushes? Everything looks to be hard soldered in. If so, where is the best place to buy replacement?

edit: I found a part number 22-18-0082 for the set, but no one online seems to stock it.

Locate & Contact an Authorized Service Center - Might beat up to a two week wait.

Wiring Diagram - Scroll down to the bottom of the page
https://documents.milwaukeetool.com/55-40-2670.pdf

 

[finn]

Brushes look ok to me, at least compared to some of my old tools.

Sparking is probably due to a dirty / worn armature / commutator, so open up your wallet.

 

[Wamsutta]

Try cleaning the contact surface with a brass wire brush; that's something you're supposed to do anyway.

 

[JohnDeere1]

Brush looks fine it's time to hit pawn shops for a new one around here they are $20-30

 

[The Cobbler]

at first look I thought the brush was OK, till I realized that the wire is bottoming out on the case of the saw, so yes, I would agree the brushes are worn and need replacing

 

[6PTsocket]

Follow the wire from the brush. It should go to something removable without a soldering iron, quick disconnect, screw terminal, etc. That should be what you get as a replacement. You can get parts directly from Milwaukee. There are a number of things that can clean up that armature. Start gentle. I would start with a pencil eraser, ink eraser, crocus cloth. It is brass and you want to clean it up, not tear it up. More than likely changing the brushes will do the trick. Your brushes are designed to stop before you have metal on netal and do damage. When they reach the end of travel and continue to wear, there is poor contact, sparks. This can pit up the armature. Replace the brushes.

Sent from my SM-G900V using Tapatalk

 

[rippledabs]

Hey guys, thanks for the advice. I took a closer look, and the wire is too weak to be able to stop the brushes from contacting.

Here is what's happening. I go full power on the sawzall, then after about 30 seconds, the power cuts off. All that time, sparks are flying everywhere. The voltage reading to the brushes is zero, so the internal switches or mosfet somewhere is cutting the power. After it cuts out for the first time, I can turn it on again for a few seconds before it dies again.

I'll clean up the armature to see if that does anything. If not, I guess it's into the garbage pile. Maybe time for a brushless.

 

[royesses]

That brush does not look very worn to me. Some 400 wet or dry paper will clean the communtator but the sparking sounds like something shorting out, maybe something stuck between two commutator segments- just a swag.
Here's a schematic and parts list with prices. The trigger/electronics cost$60.00:
http://www.toolpartsdirect.com/milwaukee-2621-20-g09a-m18tm-sawzalltm-reciprocating-saw-g09a.html

 

[Corndoggeh]

Check the commutator bars for any broken wires or chips/breaks on said commutator bars or for any blackening on the windings.