No start...sometimes

[Nlb7928]

So, once I fixed my faulty ground to my starter I am consistently getting my starter to turn. However, with the spark plug in, it either goes slow, or just spins on the belt.

When I remove the plug, it spins normal.

I've set the valves at .005 and no luck, at .010, I could get a few more rotations out of the engine, but not enough to run it, and that doesn't seem to be the spec.

Both valves look to move freely and I can compress with my thumb.

What am I missing? Maybe the exhaust is plugged? Seems unlikely.

[CP241]

Tighten the belt. It’s gotta be pretty tight.

Valves should be .005

Clean all the connections power and ground (I think I mentioned that before)…

What size is your battery? CCA?

(Again) these engines have high compression and it takes a lot of oomph to get them to turn over past the compression stroke sometimes. You need good connections, a good battery, and a healthy starter and belt. Stick with an oem belt and starter/gen the aftermarket ones are junk.

[Nlb7928]

The autozone test yesterday showed the battery rated at 700 CCA, but tested at 825 CCA.

I've got the belt as tight as I can.

I think I've got an electrical gremlin. When the plug is out, electricity flows easy, but when the plug is in and there is resistance, then my electrical shorts out. You're right, I need good connections, I just have to figure out which one it is.

Is it most likely engine wiring, or could it be in the electrical box (like a micro switch)?

[Alby]

Try disconnecting the yellow wire from voltage regulator to starter and see if it cranks faster. Mine was doing the slow spin and engine wouldn't start, so the guy i got cart from disconnected yellow wire to start it. Well battery wouldn't charge, so after many questions I had I replaced voltage regulator fully charged the battery and engine started fine. So my issue was bad VR and low battery.

[CP241]

Removing the spark plug has nothing to do with electrical anything. It relieves all the compression so the engine spins easily.

Your connection problem, if there is one, is going to be one of the heavy gauge wires. Check voltage at the starter itself when cranking and see what the drop is.

Small wires can create different types of problems, but not what you’re experiencing. I’d focus on the high current parts of the system. Battery, solenoid, starter.

[Nlb7928]

I appreciated the "small wire" vs. "Big wire" explanation. I had never heard that and it makes sense.

So I replaced the ground on the starter which didn't look all bad, but now it's new. I feel like the starter is getting consistent power now.

The starter measured 12.5 at the POS terminal.

I'll try to attach my video. It will spin through intake, compression, and power stroke, but then struggles by either spinning in the belt or not turning the motor over.

With the valve cover off, I can compress the exhaust spring, but it's about gotta be the valve is stuck.

I had the jug off 2 or three years ago when I was dealing with a backfire issue and the valve shaft was Carboned pretty bad and wouldn't move freely. Must be doing the same.

I knew the plug isn't connected to the starter/electrical. It made sense in my head but must have came out poorly.

Thanks for all the help, CP241!

[CP241]

Also, maybe easy to overlook. But make sure the starter is actually spinning the correct direction. Clockwise or counterclockwise rotation, depending on what year your cart is. You never said. 96 and prior should be CCW and 97-up should rotate clockwise when looking at the clutch.

[Nlb7928]

https://www.youtube.com/watch?v=Xh17a7tQf48

I tried to post the link. I couldn't figure out a better way, so it's just a short video on my YouTube.

I hope I don't have to tear it apart. This isn't even the problem I started out with. Just work, dangit!

Edit..I had the valve cover off, again, and the valve is loose. I could compress it, and watch the stem go up and down while starter engaged. I guess I'm back on electrical or battery.

[CP241]

It’s struggling on the compression stroke. This is fairly common. Except once it gets past it, they usually spin up and run. Yours isn’t.

For giggles, try a different battery or hook jumper cables up to your car and see if it makes a difference.

After that can start checking for resistance and voltage drop, but I’d start by just trying another battery.

And double check your ground connection between the battery and the chassis of the cart.

[Nlb7928]

Short version: it's the starter.

I started by sanding all my grounds. No help. Jumping with 2 different running vehicles, with 2 different sets of cables...no help. Tried a brand new battery my dad had, nothing. Still getting 12v at starter, so I finally popped the belt off and the starter wouldn't spin. Bump it a little and it'd go like a champ. When I thought I verified it before, I bench tested it a few hits and never did it not work.

At least I can stop being pissed off that I can't figure it out...and now I can be pissed off that I'm dumb, but what else is new.

Thanks for the help. I'll post once I take it to the electric shop, get it tested, replaced, reinstalled, and the rear bench put back on again.