Hi all,
its been a while since ive been posting and all, life has just been happenning.
But i finally got a chance to get the 340 kit on my 09' and when i went to start it up it fired right away but had a "tap"in the top end.
Its comming from the cam chain area and my dad, a long tie dirt bike rider/motor guy, and myself have no explanation for it...
we tookj off the cams again, loosesned and tightened the cam hain and just can figure it out...
anyone with suggestions, they would help greatly! thanks!
-JACK

 

Stock cam chain tensioner? Pull it out, move it 1 tooth tighter, and install. Bet the noise goes away.

 

Yeah, though it's hard to make a solid noise diagnosis over the internet, I'd bet with EMS that it's likely a cam chain/tensioner issue. This is a common element with these engines, as the auto tensioner can be somewhat finicky. Just for further clarification, did y'all mess with the head to any degree where you removed the valves, did a valve job, etc?

 

The only thing i did to it was switch the cylinder and piston out, no valve adjustments or anything.
The cam chain is VERY tight without the tensioner in and i cannot figure out why.
After hearing the tap i took out the tensioner to see if that was the problem and it still had the noise.
thanks guys!

 

Did you reinstall the guides right and put the lower chain tensionerbolt and spring in right?

 

From my experience the cam chain can feel very tight with the tensioner out, but when the motor is running the chain won't be as tight and will make noise.

I would do as the others said and reset the tensioner and reinstall and see if it helps. Actually I would get the Krieger manual tensioner and install it.


It sounds like you ran the engine without the tensioner installed, I don't know if the cam chain can jump teeth without it installed or not, but you might check TDC and that the cams are still correct.

 

i had the head off and everything today, it seems that the chain wasn't as tight as i thought, But the gasket that Bill Blue sent me was actually smaller than the piston and overhanging in the cylinder a little.

 

That can be very, very bad. This situtation - smaller gasket ID than piston diameter - can cause catastrophic engine failures if the piston actually hits the gasket. If I were you, I would - at a minimum - pull the cylinder and piston, fully inspect the piston for a collapsed top ring land, and check for signs of damage to the bottom end bearings. The problem with checking the bearings by feel in this situation is that there may have been damage initiated that will take time to fully develop.

Best of luck to you.

 

got it running properly with the proper gasket.
no damage occurred because i did not have it running for longer than about 15 seconds.
luckily everything is ok now.
thanks all!
have a good one!

 

Proper gasket?

Did you put the old one in instead of the new one from Bill?