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Posted

When did this valve hitting the head problem start ? After you'd adjusted the valve clearance ? Or is this valve hitting the head problem the thing you were trying to fix with a valve clearance adjustment ?

I think first you should recheck your valve adjustment, possibly even backing the adjustment screws about a turn or more and seeing if that fixes that problem.

If the valve hitting the head isn't curde with a different valve adjustment, then it might be caused by the cam timing being out. That you do as I said earlier, you take a bung out at the flywheel and take the cam chain cover off and align the marks on flywheel and cam with head. Best download a manual and have a read though.

 

Posted

I got the timing off and busted a rocker. i replaced the rockers and adjusted the valve clearance to what the service manual suggested and put it back to the correct timing. when i tried to start it it busted another rocker. i replaced that rocker put the timing back on and readjusted the valve clearance and tried turning over the engine by hand it still hits the exhaust valve. Im wondering if the service manual has it wrong or if something is still screwed up. I’ll try to back the valve timing up till its not hitting but i hope that doesn't mess anything else up.

Posted

If a valve clearance is set too tight, way too tight, the valve can hit the piston. More commonly though the cam timing is the problem.

I'm guessing you must be setting the timing wrong. You are finding a "T" mark on the flywheel, and aligning a slash mark on the cam sprocket with a mark on the center top of the head ? Once the timing is set, turn the crank carefully for two full turns, feeling for any sign of a valve hitting.

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