1982 Yamaha G1 Gas has no spark

[Pete777]

So a friend and I saved this cart from crusher. I can't get a spark. I have a new spark plug, new coil, correct ohm readings from pulsar and coil in the magneto, new CDI from a guy on ebay, and a new ignition switch. The only thing that doesn't spec out is I am getting 15 ohms through the coil and read that it should be 350 ohms. So I got another coil.. same result.. 15 ohms.

It had a bad short when we got it. The ground wires were fried. The short turned out to be in one of the solenoids. I couldn't find any out on the web so I got 4 12v continuous use solenoids that work. It took me awhile to understand running the starter/gen forwards and backwards. I pulled the flywheel to check the mag and found it so full of dirt that I pulled the stater to clean and check it.

Here is my solenoid redesign. That works great..

[Lochlin]

Man, you did a lot of work on that cart. Nice ingenuity on the solenoid set up.

Are you getting those ohms specs from the manual? 15 ohms actually seems like a lot to me and 350 seems way too much. I can't speak to the G1 coils but with my other old carts the coils typically have 1.5 to 3 ohms depending on the application. I could very well be wrong with the G1, I am just throwing it out there.

Did you ever get a service manual? There is one here and it contains detailed testing procedures for tracking down "no spark" issues.

https://buggiesgonewild.com/showthread.php?t=129227

[Pete777]

Thanks! It was a bit of work on the solenoids. I got the specs from searching around but much appreciate the tip on the manual!!

[mikeasis]

Originally Posted by Pete777

Thanks! It was a bit of work on the solenoids. I got the specs from searching around but much appreciate the tip on the manual!!

Can you share more on what solenoids you used as this could come in handy for a lot of people

[Pete777]

Here is a like for the Prestolite solenoids I used

https://www.ebay.com/itm/Prestolite-...72.m2749.l2649

[cgtech]

It's good that a new guy (on this forum) gets it, and shows "another way to get it done" is awesome, especially for the guys who arent going to have access to the "proper solenoids". I appreciate your work here, because even explaining just how it works is hard sometimes. You totally did a good service to old G1 owners here.

Now I just hope that people dont get that confused with the original setup, because trying to explain the difference between 2 OEM solenoids, and your 4 solenoids might be tricky if they dont understand what's happening.

Not to be mean to anyone else, but "I wanna fix it, and i cant deal with a wiring diagram" is real hard to fix. (I want to help, but I have a terrible time helping them). Thank you again for that awesome G1 fix option. Lord knows those parts are expensive & hard to find for OEM style.

I would have to suggest against this approach on the 36v "electric G1", because those solenoids arent a robust solenoid in the applications requiring several hundred amps every time the pedal is pressed to the floor. (Works perfectly on a gas cart that only requires higher amp loads for a few seconds at a time)

[Pete777]

Your welcome and glad you found my design useful. It took me awhile to understand the factory wiring diagram with respect to the starter/gen solenoids. I didn't fully understand it until I found a bench test for the starter/gen and realized how it switched the current to run the motor both ways. Which was a mind bender for me. I have run a dc motor backwards by switching the + and - but never messed with a "4 pole" dc motor that was no less a gen running at the same time.

I didn't realize because of the picture that I had ordered a 36v version of what I needed..oh well that's what returns are for!

So I got all the specs from the manual you gave me and all ohm readings and voltages spec out except i am getting nothing out of the cdi on the orange wire. That is saying to me that I have a cdi issue. What is a good source for a cdi?

[mikeasis]

this setup was on a cart i bought and it worked well.
its a cheap chinese cdi for a small 125cc engine modified to work both forward and backward

post #52
https://www.buggiesgonewild.com/show...t=76176&page=6