Starter wont turn after warm up

[Lochlin]

I posted about this a couple of weeks ago and thought I had a bad starter. I put a new starter in and thought that took care of that but it didn't after all.

87 G1, here's the deal:

When the cart is cold the thing fires right up and runs like an animal. It will keep running well until the engine is warmed up at which time it keeps running. However, once the engine is warm and you stop the cart, like at a stop sign or something, it wont restart. The starter wont turn, no solenoid clicks, nothing. Now, given 15 mins or so of cool down it fires right back up and runs great until the process repeats. Of note, the cart does start again after a stop and the engine is still cool.

My initial thought was that heat was affecting the old starter hence the replacement. However, the same thing is happening with the new starter.

I did a pretty good wiring inspection this afternoon and nothing seems amiss. Even with that, logic kinda says that any wiring mishaps would cause the engine to not run when cold as well as warm.

This cant be cdi-related, can it? Seems like if the cdi was screwed up it wouldnt run when cold and the starter would spin no matter.

This has to be something related to the starter circuit, right? (starter, key switch, solenoids, aossociated wiring?) I am going to study the wiring diagram but, sheesh, the starter circuit is pretty straight forward. This is different for sure.

[cgtech]

I would be checking the small wires at the solenoids for power when in "failure" mode. Also check the battery terminal (is power still present downstream).

[Lochlin]

Does that solenoid relay ever go bad on these? Its the whole "runs cold, not warm" that has me perplexed.

[cgtech]

Yes, they do, and when that happens your wallet will hurt.

[sho305]

All the older yamaha are known for wiring issues, but when you are talking 80s-90s carts its hard to expect more from them. The good part is its cheap to fix wiring. Yes small connections are issues as well as battery cables. I have filed the inside of my post clamps and they still cut out on a new battery, going to put new ones in this summer just keep forgetting to measure them out. All the small wires on my solenoid (my G9 but they all have similar issues) all have new connectors crimped on them. Also note that yamaha are ground wired only the block is ground usually not the frame, so you have to check all the ground wiring for faults too unlike in a car. Lastly don't forget the battery posts mine have been a pain for many years for no reason, I swear the lead is bad or something lol.

[Lochlin]

Thanks for the input. I was hoping to not have to tear this wiring harness apart but it's looking like it's inevitable.

Last question; on the rear inner fender, right next to the CDI and above the solenoids there is what appears to be a relay of some sort with 4 spades. There is no mention of it in the service manual or the wiring diagram. Is this really a relay or just a junction to make wiring repairs easier? By the life of me I don't understand why there is 12v in and 12v out of this device.

[Spicyunicorn]

If I remember right its a relay that delays the starter when switching from forward to reverse

[meimk]

You may have already checked it, but my first thought is the stop switch. I know it doesn't really get exposed to engine heat, but they can certainly stick. It's been a little while since I worked on a G1, but I recall some general corrosion issues of the switch and wiring- hanging out there under the floor and all.

[Lochlin]

Originally Posted by Spicyunicorn

If I remember right its a relay that delays the starter when switching from forward to reverse

Hmmmmm, if that's the case that bugger just went to the top of my suspicious list. I couldn't help but notice there are no part numbers and that no cart part suppliers sell replacements for that. Probably because it's bypass-worthy. All my other carts wire direct to the solenoids with no delaying relays needed.

I'll check things out further this weekend when I get back to the camp.

[Spicyunicorn]

All you need to do to bypass it is connect the two white wires together