|Posted on Saturday, May 28, 2011 - 09:52 pm: ||
Bought a race bike that had it's last engine built by a bozo.
A thrust washer was in the cam area and the rear set of cams inhaled it. Stopped everything in the lower end....except the crank and reciprocating parts. I fixed all that but never popped the heads off to have a look. Starting it up tonight has it back firing up the TBI. Therefore...bad intake valve.
Are Buell motors interference motors? If so I'm wrenching again....
Anyone have a quick and dirty method to determine which jug has the bent valve? Can the motor be easily turned over by hand now that it's all back together?
|Posted on Saturday, May 28, 2011 - 11:37 pm: ||
rear end on a stand, pull both plugs to eliminate compression, turn engine by spinning rear wheel. Use 5th gear if necessary.
It's definitely an interference engine.
Non-interference should hypothetically allow a piston at TDC while both valves are wide open. These don't even come close to allowing that.
|Posted on Sunday, May 29, 2011 - 06:33 am: ||
pressurize the combustion chamber with an air hose thru the spark plug hole at TDC (both intake and EXH valves should be closed) and the pressuized air will blow thru which ever valve is not sealing (bent)
|Posted on Sunday, May 29, 2011 - 03:10 pm: ||
Just do a compression check simple as that. Then do a leakdown test to determine which valve it is, but you'll probably see the bent one when you get the head off.