Engine/Transmission (1994 - 1998) Starter Brush Replacement Question

[Extreme1]

I have the starter out and apart. The problem is trying to get the worn out OEM brushes detached from the brush plate and the copper ring. I've got a soldering iron against the brush plate and the whole plate gets hot but they don't let go. What's the trick?

 

[tp0d]

With the size of the solder joints, you need one hell of a soldering iron. A roof flashing iron comes to mind, dunno the best place to get one. Be sure to get some kind of acid paste to clean the joints before re-soldering, or you will get a weak joint.



good luck



-j

 

[B.G. Smith]

I have the starter out and apart. The problem is trying to get the worn out OEM brushes detached from the brush plate and the copper ring. I've got a soldering iron against the brush plate and the whole plate gets hot but they don't let go. What's the trick?

You need to take it to a starter/alternator shop and have the brushes re- attached, if you use regular solder it won't stay. I believe they use an electric spot welder? bg

 

[Howard Durand]

BG is right about the brushes being welded but even if they could be soldered you would not want to use acid paste or acid core solder on them or any other electrical equipment. It is corrosive and most likely will cause a short circuit.

 

[Willys]

Could a butane, mapp, or propane torch be used?

 

[Howard Durand]

The braid is welded to the copper but it could be removed with a small grinder.

It would require some experience in soldering and, if you have that, I see no reason the new ones could not be soldered in place.

You will need to use a heat sink to prevent the solder from wicking into the braid while allowing you apply enough heat to the connection for a good flow.

What it comes down to is that if you don't don't have any soldering experience this would not be a good place to learn.



If you feel you want to try it, you could practice with the old brushes first.

 

[tp0d]

Solder flux will not cause a short circuit. It is critical to a good joint. Flux stops oxidation of the metal when heated to temps high enough to melt the solder. The joint should be cleaned once it is set, which eliminates any stray acid from the area.



The original brushes were soldered on, why couldnt the new brushes be soldered also? Welding also introduces voltage to the starter, which could harm something inside it. Care has to be taken not to overheat the brush pads, and everything would be ok. .



you`ll never get a grinder into that small area. A dremel, maybe, but you risk damaging the solder pad, which could easily be de-soldered with the correct iron.



-j

 

[Howard Durand]

I wasn't referring to a bench grinder.



As far as how the joint was made, It doesn't appear to be a weld as such but the joint was definitely made under pressure and, I would assume that it was heated electically instead of indirectly from an iron. The bonding material appears to be of a high tin content which would probalby be stronger than some of the softer solders.

I don't think it is silver solder since it can be scraped with a knife point. That would explain why he can't get if hot enough to come apart.

I stand by my opinion about acid cleaners and acid core solder for electrical or electronic devices. I will not ever use them nor would I advise anyone else to.

They are fine for copper pipe.

 

[Extreme1]

Got the starter back together that night. I used to do strain gauge work so I'm pretty handy with an iron. There is a size limitation as to how big an iron you can get in there. Also, I got my brushes from a place in Minnesota and they had metal tabs attached to them already. All I had to do was solder the tabs to the brush plate and the copper ring.



I did use a dremel to remove some of the original copper tab that is clamped to the brush braided wire to provide a smooth surface. I used silver solder (I do for all my electrical work, the other stuff is for plumbing) and got a good bond between the existing parts and the tabs on the brushes, I don't think you could solder to the braid very easily. This was fun enough as it was.



It seems to be OK, one of my fuel lines just developed a leak so I have to crank it pretty long to get it running. That is what finished the original brushes off in the first place so I'll be fixing the fuek line problem today.

 

[Howard Durand]

Thanks for the report. I agree, it is fairly close quarters. I was looking at the brush assembly that I removed from a starter that got toasted when the contacts stuck.

A very small acetylene torch would really work nice for that kind of soldering.

The only iron I have that would generate enough heat is way too big.

I just replaced both of my fuel hoses with a set purchased from Larry B at Foster Truck.

All of the info I have read on these hoses indicate that the return hose is 5/16" and the supply hose is 3/8" but, while I was replacing my hoses, I measured the metal lines on my 94 and found that they are both 5/16" which explains why one of them went on real easy. Since your sig shows that you have a 94, you may want to check the lines before you buy the hose.