leak down test

[Mike Thomas #828]

when performing a leak down test....when is the cylinder exactly at TDC?...when the crank pulley notch lines up with the case line? or when the distributor rotor lines up with the notch in the distributor housing?....the reason i ask is because they dont line up simultaneously....when i have the distributor rotor lined up with the distributor notch, the crank pulley notch is about 1 centimeter passed the case line.....i seem to remember reading something about a 4 degrees timing advance...is this accurate?....

having said that...what is best to use fot a LDT?....if it is the rotor/distributor notch...then i would assume that for the rest of the cylinders after #1, you have to advance the crank pulley notch the same distance past the case line every time to get TDC...is this correct?

also, is it the center part of the rotor that should line up with the distributor notch or the leading edge (right edge when viewed from top) of the rotor that should be lined up??

 

thank you for your answers!