When i removed the oil pan to check things out and looked at the Mag coil i found RTV silicone covering the coils. The oil had caused the RTV to start falling off. I could just see this stuff getting into the oil line. What is the best stuff i can cover the coils with that oil will not affect?
I believe that JB-Weld, that is, the long setting stuff, would be fantastic. It holds up to oil and temperature very well.
But unfortunately, from the look of those coils, you'll probably have to send that mag ring off to get rebuilt.
When I was a poor 16 year old in 1970, on a limited budget attempting to restore my newly purchased 1926 Model T Coupe, there was no Forum, nor anyone around to tell me I could not restore my magneto coil on my own. When I removed the mag coil, the cloth insulation was in shreds, exposing the underlying flat windings which were fortunately still covered in the shellac coating. I soaked the coil for several weeks in a big tub of mineral spirits that just covered the coil windings, stirring it with my hand now and again whenever I would pass the tub and whenever the mineral spirits would turn black, I would change it out and did this until the mineral spirits remained clear, indicating that all of the oil was out of the windings. I then let it dry for a week. After it was thoroughly dry, I hand brushed it with several layers of GE Red Glyptal.
That magneto worked for the next 40 years, and still worked when I removed it in 2010 and sent it to Wally of Total Recoil to be rebuilt. He uses clear Glyptal. So don't always listen whenever someone tells you something can't be done. If you are confident in your ability and/or have no other way to "get 'r done", go ahead and try it your way. You may surprise yourself, but, keep in mind, if you are not fortunate like I was, to have a good magneto, in spite of the bare windings, it will cost you in labor and effort if you find that the magneto does not work after all that effort. I just had beginner's luck. If I had to do it all over knowing what I know now, I would probably save up my money and have the magneto rebuilt. Jim Patrick
PS. If you want to attempt the method I used in 1970, do NOT use lacquer thinner or anything that will attack the coating covering the flat windings (such as alcohol or ethanol). Mineral spirits will not attack the insulated coating like other stronger solvents. Jim Patrick
For the price of a rebuilt one, I would have it rewound, it sure is a pain in the ass to do the second time around, then it gets expensive.
Jim is right. A magneto ring can be rebuilt by yourself. I'm soon going to rebuild mine using kapton tape for the insulation between the windings and pot each coil in some sort of good, high-temp epoxy.
However, it's a long and tedious process, especially if you're doing one for the first time and learning as you go. So I would say that it's not for the average do-it-yourselfer, but it certainly can be done.
You can buy rolls of the insulation to recover the strips. Of course it all needs to be unsoldered and unwound, which is not high tech, but can be time consuming.
I don't think trying to apply anything like JB weld to the coils is going to be satisfactory for any length of time.
I'm still looking for a solution with which to coat this coils. JB Weld (again, the slow cure stuff only) is the best I've come up with. Anyone have any other ideas?
When all else fails, read the directions. In this case that would be the MTFCA book, The Electrical System. That tells you in considerable detail how to do it.
If they are freshly wound with new insulation then you can use shellac and even JB Weld might work fine. Anything applied to old used coils is not going to be useful.
Thank goodness for that book! I've read through it several times, and anyone intending to work on the magneto should do the same! I just don't where to find boat resin in these parts...
Tractor Supply maybe? Isn't there a Home Depot in College Station?
He may not be EF Nutten but when Joe Bell speaks i listen!! Bud.
Bill, I have tore many of engines apart that people have tried to seal the coils with any thing from fiberglass resine to silicone the problem is the coils are oil soaked and you can never get all of it out and the results are the stuff comes loose and goes through the whole engine and plugs up everything and that will lead you to another tear down.
I was never clear on what 'Boat Resin' was. I believe most fiberglass boats probably used polyester resin. However, when covering wooden boats with fiberglass cloth, polyester resin is frowned upon. Wood boat guys use high dollar epoxy resin. I'm not 100% sure which, if either, either of these is what the book is calling 'Boat Resin'.
I never thought to try Home Depot. I'll certainly see if they have it. Thanks for the heads up!
Since it is buried in the engine, the smart thing to do would be to get a top notch rewound one from Wally Szumoski. Anyway, that's my 2 cents worth.
Might try some outfit like Overtons. Possibility that Bass Pro could have it too. What about fuel-proof airplane dope? You can get that at pretty much any hobby store.