The 'E' Type Forum

I have been trying to repair the motor of the windscreen washer pump for my '67 S1.5 for the second time with little success. The carbon blocks have come off the copper springs. The first time I did it I bought a spares or repairs unit and salvaged the carbon brushes on the copper springs. Reluctant to do that again I have tried soldering the carbon blocks back on without any success. If anyone else has had these problems is there a good modification or do people tend to buy a new replacement unit? It's annoying to junk the whole lot just for the brushes!

I had the same problem with the older 2sj unit. I wasn’t able to successfully solder the brushes back on. It’s a shame the big parts suppliers like SNGB couldn’t get suitable springs/ brushes made so we can save the original washers. Maybe this is one for the group that meets with SNGB to raise??

Post some photos of the brushes.....someone may know of something similar...there are plenty of different brushes about....you should be able to adapt something....Steve

Yes, I’m all over carbon brushes on eBay but the problem of soldering them to the copper springs remains.
I agree, it would be nice to be able to buy the soldered brush + spring assembly as a spare.

Whats the problem soldering......can we try to help...Steve

Maybe one of these can help with the soldering or welding....

https://www.amazon.co.uk/dp/B09ZXRXRPQ? ... ct_details

Not 100% sure whether is suitable for this application though....

mgcjag wrote: ↑

Thu Feb 02, 2023 7:19 pm

Whats the problem soldering......can we try to help...Steve

The solder doesn't seem to adhere to the carbon brush. I just wondered if anyone else had had any success doing this? I'm not sure how robust the design is and how frequently they fail?

Ross...have a look here...or how about useing a standard type brush with a flexi wire..bond carbon to your spring with epoxy and solder flexi wire to the spring...Steve https://www.tr-register.co.uk/forums/in ... eeded-pls/ just for info this is the type of brush discussed in this thread

Thanks Steve, Yes, they are the same ones and the problem is the same as described in the TR forum. TBH I'm not 100% sure if the soldering problem is my lack of skill or material incompatibility. I'm torn between spending £100-170 on a replacement or trying to repair it with a shunt wire + glue.

Very difficult to solder onto carbon brushes. Originally they were copper coated (not sure if this was done chemically or electrically) which allowed the solder to adhere. The copper coating was quickly worn away on the contact area by the rotating commutator.

Without the copper coating you will struggle although I have heard that if you really heat up the carbon brush with the soldering iron for about a minute you can apply solder and wire. Not tried it myself but maybe worth a go.

These look interesting.....https://www.ebay.co.uk/itm/TRIANG-HORNB ... ect=mobile

It's possible that the original brushes were/are a copper alloy which were used where a motor only worked periodically so that wear wouldn't be an issue.
You may be able to apply electroless nickel or a PVD coating to carbon. Both would be expensive.
Phil

Thanks all for your advice. I tried heating the brush with a small blow torch so it was certainly hot, maybe too hot. Part of the problem is that the notch on the back has disappeared. I think I’ll try a brush with shunt wire + glue.