I am trying to do a leak down test on a Kohler K341.
I am having trouble finding precisely TDC. The spark plug is over the exhaust valve so I can't stick anything in there to feel the piston, right?
I have the breather cover removed and can bring it to the point where both valves are closed. I rotate the crankshaft by hand until they both close. Then I keep going until the exhaust valve begins to open, then I back it up to when they were both closed. How accurate is this?
Do I need it to be very precise to perform Valve Adjustments and Leak Test?
Also: How do you go about locking the crankshaft in place for the Leak Down Test? Vice Grips over the drive shaft? 100PSI seems to be like a lot of pressure, and I won't be able to hold that still.