Predator 420 swap starting issues

[JD466US]

I have a 93' EZGO Marathon that I did the Predator 420 engine swap using the Vegas Carts kit. The first year after the build I had zero starting issues. We would drive it all around, shut it off and it always restarted. Then last year I started having issues with it restarting after driving it around. I thought at the time that maybe it was heat related since summers are hot here along the Carolina coast and I was using the original Hitachi starter that was on the cart. I added a electric fan and it seemed to help somewhat but would occasionally still do it. Well this winter I decide to put a new Reliance starter/ generator in it with a new Optima battery in it. It was fine for a while but is now acting up again. The generator is out putting about 14 volts so its working. I am still using the carts original starter relay and voltage regulator. I am wondering though would the 35 lb. valve springs I installed cause an issue if it's on the compression stroke? I just recently discovered that if I pull the pull starter a half revolution the cart will start. Anyone ever had this issue before?

[raydhd]

If your valve lash is too large this will affect the compression release on the exhaust valve and make the engine harder to turn over.

[JD466US]

Thanks, that makes sense. I'll check that. After changing the springs when I did the swap I set them but never bothered to recheck them the again, and I should have.

[slonomo]

The compression release can also get "sticky" from oil buildup. I've had this happen in a couple small engines of mine, one was a Predator. I recommend using a synthetic oil because they typically have more detergents in them that will prevent sticky buildup and sludge. Also frequent oil change intervals in hot weather will help. In our landscape equipment we used to change oil twice a month in July and August.

[sho305]

And put a zinc additive in it. When I put high ratio rockers in the comp release actually worked better. But I never had any starting issues on my yamaha it always spun over fine just like stock. The most problem I had was the belt slipping. Finally I found a cogged starter belt not had any problems with it.