Reverse Shift Coil 1963 75hp

[yorab]

Motor in signature. The reverse coil looks like the epoxy is pitted and cracked in a few places. The ohms check out at 7.9 ohms and I believe that the wire showed 12 volts when the engine was together a few years back.

Because of the ungodly price of these coils, I'd like to reuse this one, especially since it works as designed. However, I don't want any of the epoxy to break off during operation and get between the gears and in the bearings.

What are some ideas for repairing this coil? I'm thinking of breaking off any loose pieces with a pick tool and then filling in the pits and cracks with new epoxy. I'm hoping that the new epoxy will hold everything together and keep particles from breaking off.

I know that this question is way out in left field and even some of you guys that have been working on these engines for decades may have never run into this before. There may not be a good way to repair this, but I'm open to ideas if anybody has any. Thanks.

 

[Daviet]

Re: Reverse Shift Coil 1963 75hp

I did the same thing quite a few back. Make sure to use brake kleen, or something like it, to remove all traces of oil. Then spread a thin layer of epoxy and let it cure completely. You got nothing to loose by trying.

 

[emckelvy]

Re: Reverse Shift Coil 1963 75hp

Check out this 3M product, Scotchcast insulating epoxy resin, it's specified as an electrical insulator for oil-filled cabling and similar uses, seems it would perfectly fit the bill for this application as well:

http://www.galesburgelectric.com/3M-3570G-Scotchcast-Electrical-Insulating-Resin.html

Here's more info from 3M website on the product:

http://solutions.3m.com/wps/portal/...24Q5_nid=DGMM8KPX9ZgsQT6SM2Z6BCgl10HBB8WLJ7bl

HTH & let us know how it goes.............ed

 

[yorab]

Re: Reverse Shift Coil 1963 75hp

I just ordered the Scotchcast from the local electrical supplier and I'll pick it up tomorrow. I'll try it and post some pics to let you know how well it worked.

Daviet, you mentioned that you did the same thing before. How did it work out?

 

[Daviet]

Re: Reverse Shift Coil 1963 75hp

It worked well, I lost track of the engine after a couple of years, was sold to someone out of the area, but had no problems that I know of.

 

[yorab]

Re: Reverse Shift Coil 1963 75hp

I tried the Scotchcast but it didn't work. It was almost surely my fault. The instructions didn't mention how long I had before curing began so I didn't take enough time to knead the two parts enough. The Scotchcast comes in a package that looks like two ketchup packets separated by a thin plastic barrier. You have to wrinkle the package to break the barrier. After that, I kneaded about 20 times or so and then I applied. The consistency is like thick maple syrup. It is perfect for filling in pockmarks and thin cracks. After 2 days, the epoxy was still a bit soft. If kneaded properly, I believe that this is a very good product for this particular task.

I picked up some general purpose epoxy called Propoxy 20. It is more of a putty consistency so it doesn't fill small cracks as well as the Scotchcast, but it worked out ok. I kneaded very well and then applied a small amount to the coil. I then used some water on my finger to spread and smooth the epoxy a bit. To be sure that the epoxy wasn't too thick, I pressed the gear hub into the coil and rotated a few times to knock down the high spots.