Re: (ET) New here, E15 and E12

First off, many thanks to Nick Skinner for all his troubleshooting assistance. His knowledge of the details of how an Elec-Trak works, including which components on card 1 relate to each speed was incredibly helpful. With Nick's help I was able to replace some more components on Card 1 to get more speeds but the operation was sporadic. Probably because the components came from other old cards I had...

In the end I decided to install a new Card 1 from Jim Coate. I did not think it made sense to keep chasing things around on a 50 year old card. Even If we got it to work, future component failures are almost guaranteed to happen on the old card. The new card was not that expensive and it should make the tractor trouble free for many years to come. Harold Zimmerman is also a great resource of knowledge and parts.

So installed the card and everything worked perfectly - for the first try of all 7 speeds. After that it only had the first 3 speeds as the FW relay would not engage. :-( A manual push of the FW relay got all my speeds back. The coil resistance in the FW relay turned out to be about 3 times more than new FW which I happened to have in my parts bin. A quick swap of the FW relay has it working like new!

Here are some basics Nick informed me about that would be of help in troubleshooting any issue.
Get a copy of the “Simplified Troubleshooting Guide”, goto https://www.myelec-traks.com/poppubs.html and download a copy.
Wash Card 1 with isopropyl alcohol (normal drug store 70% is just fine) and an "acid brush" you would find in the plumbing department. This will stop any leakage currents, and will also help to prevent corrosive damage.
Nick stated that he found the card components (scrs and transistors) are pretty reliable. However he replaced all of the capacitors with new. Capacitors have to be functional for the SCRs to trigger. He had a bad SCR for the PTO, which he replaced with an NOS component from Jim Coate of http://www.ElectricTractorStore.com.
Check that the wiring on the relay is OK and that the terminals are OK. Other than that, just chase the wire route. I did not look close enough and found that a wire was disconnected. It got me the first speed forward and reverse again but I’m still working on the other speeds.
Verify that Card 1 Pad 4 isn’t putting out voltage when you enter speed 1. If it is, then there is a broken connection somewhere between Card 1 and the L contactor.
If not, make sure pad 6 on the Card 1 is getting 36V when the speed selector is in neutral. This is required to ‘reset’ the SCR. If it is getting voltage at neutral, I would suspect capacitor C2 (20uF @50V) (cylinder to the right of CR109), SCR 102 (square with 3 prongs to the right of R107), or a broken lead or trace on the board.

Good Luck!

Regards,

Dean A. Stuckmann

5432 County Road U

Newton, WI 53063

On Sep 22, 2021, at 8:54 AM, joeaverage frontiernet net wrote:

Hello folks, I just joined the list yesterday. I joined the GE Elec-trak universe just a few weeks ago with the purchase of an E15 and an E12S.

The E15 has good batteries but needed a little TLC to get moving. I've learned alot reading the archives here and elsewhere.

I have everything solved but card #1. There is a unijunction transistor labeled 103 above the yellow capacitor closest to the resistor bank card.

It has a broken leg. I'd like to solder in a replacement but I can't read any part numbers on mine due to oxidation. I'm hesitant to clip the transistor off to get a better look because it is my guide to installing the new one.

Can anyone identify that transistor for me? I've looked in the service manual PDF but can't find any specs.

I played with the FW relay last night and when I press the contacts together I get FWD speeds 4-7 which would be useful.

Once everything is working, I want to tear it down for paint. Maybe powdercoat it over the winter.

As for the E12S. I really like the E15. I think rather than let the E12S sit there I might restore it too. We have a pretty big patch of grass and it would be nice to have two mowers to halve the mow time.

The E12 is missing a few things that were robbed by the previous owner to keep the E15 going. I've robbed the traction motor circuit breaker myself.

Then I could sell my 1994 Cub Cadet. it is a great mower but it is noisy like all mowers and I've tired of the exhaust when there is an exhaust free alternative with these old GEs.

Thanks,

Chris in Tennessee
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