Go-Kart won't start

[GoKartNarc]

I have a 420cc predator engine on a Manco Dingo frame. It has a torque converter on it and disc brakes. The engine only has about 2hrs on it. I rode it several times before, but I had to make the engine higher and make a few adjustments to the torque converter spacing. When I work on it I take the two 22"x7" rear tires off and put the Kart up on stands. Recently I finished working on it and it started right up and it runs great with the rear tire's off. Then I put the tires back on and lower it to the ground and try to start it, but it won't. I've adjusted the idle, but it still won't start. Am I not adjusting the idle high enough? I'm concerned if I adjust it too much its going to start up and take off on me.
Any suggestions??

Thanx

 

[Karttekk]

Please provide pictures of your drivetrain setup, maybe those will shed some light. How are you adjusting the idle if it won't start or are you saying you turned the idle screw up hoping it will start and stay running?

 

[GoKartNarc]

When I have it on the stand jacked up with the rear tires off it starts right up. Everything's working fine along with the idle. Then I put the tires back on and drop it back down to the ground and then it won't start.

I will send some pictures when I get home from work today.

Thanx

 

[Karttekk]

Is the rope harder to pull when the kart is lowered? Almost sounds like something is binding or too tight not letting the engine crank with the wheels on the ground. You could be pulling the whole kart with the rope instead of just the engine. Hopefully your pictures will help diagnose it.

 

[GoKartNarc]

You know now that I think about it, it is a little harder to pull while it's on the ground. It does lurch forward a bit too. Could it be that maybe the chain is too tight? What's the rule of thumb for tightness of a chain?

 

[Karttekk]

Pretty sure It wouldn't be the chain, I would look at the belt being too tight not letting the drive clutch freewheel possibly.

 

[GoKartNarc]

I'll check it out.
Thanx again!

 

[2lz2sft]

How bad of a angle is the engine at? Are you still using the low oil cutoff switch or did you bypass it? Try bypassing it and see if the motor will run. Are you running the stock or a mikuni carb? Mikunis dont like sitting at funky angles....

Maybe take the chain off and see if it runs when let down with the tires on????

 

[GoKartNarc]

Ok well I think I figured it out. The jack shaft that's on the torque converter is all ate up in the middle. It's not very round and it might be slightly bent. I ordered another shaft. Also it has no oil sensor so I can rule that out.