After weeks of tinkering I finally did the cylinder leak down test. 80% leakage and air rushing from carb. That means intakes are stuck open... BUT... TDC when checked with camshaft pin at top does NOT line up with flywheel timing mark for TDC. The timing mark on flywheel is about an inch to the right of the pointer. The flywheel is lined up correctly on shaft and woodruf pin is securely in place (not sheared off). But true TDC (camshaft pin at top) does not match!

Does this mean somehow it jumped a tooth? Now its out of time and thats why wont fire? There still is leakage on intakes at true TDC but its less. Still too much though. SO do I have valve AND timing issues? Is it worth fixing or what? I just got info that the last owner drove it without a fan for a few months. I hope that didnt warp things...

 

More than 15% leakage too much! Does timing TDC mark line up with pointer with recoil housing on? Check that first and not flywheel against stator plate mark. Just slip on cover,turn flywheel until lines up and check cam sprocket pin location. even if off slightly and has clearance on rocker arms,then 80% way too much leakage especially if can hear air rushing through carb or exhaust!. Possible leakage through valves and piston rings.

 

Thanks for responding OPT. No it does not line up with recoil housing on. The flywheel timing mark is off to the right about an inch to an inch and a half. This is compared to the cam sprocket pin being at TDC. Air still rushing through carb. What could have caused this out of timing? Also I plan to lapp valves. How do I prevent it from jumping again?

 

Cam chain wear/stretch possible,also I would check cam chain tensioner and replace spring and any worn parts along with new cam chain. If valves,especially intakes have a sharp edge,better to replace and lapp new ones in. Exhaust valves a lot stronger,usually can lapp. Always replace valve guide seals. After lapping,NO leakage should seep from valve face after filling intake and exhaust ports with solvent/contact cleaner! Even though some manuals say a little normal,I lapp em until no seepage! Use fine lapping compound! Forgot to mention piston and rings! check for wear and if piston to cylinder clearance over .003,time to bore!