i have 135 #1,2-140, 3-125,4-115,5-120 &# 6 135. Please let me know what they should be. If they where running what they should be, would I be able to tell the difference in per ???formance?
What should my compression be on an F?
- Thread starter sambudo
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By the manual: 150 psi is nominal, "limit" is 128 psi. Difference in pressure between the cylinders should be less than 14.2 psi.
You should wet test them (add a few drops of oil to the cylinder before testing). If it brings the pressure up to normal, you probably have worn rings in those cylinders. If the pressure doesn't change, you are likely to have problems with valve seating.
Vacuum testing may help confirm your findings (see vacuum 101 in the tech page).
Fixing the problems would probably improve your performance some, although I have heard of engines that seem to run fine with lower pressures than recommended.
You should wet test them (add a few drops of oil to the cylinder before testing). If it brings the pressure up to normal, you probably have worn rings in those cylinders. If the pressure doesn't change, you are likely to have problems with valve seating.
Vacuum testing may help confirm your findings (see vacuum 101 in the tech page).
Fixing the problems would probably improve your performance some, although I have heard of engines that seem to run fine with lower pressures than recommended.
