Visit The Dirt Forum for More Information

Author Topic:   Leak-down testing
istock59
Member
posted June 10, 2002 08:14 AM
What's an acceptable % of leakdown on a race engine?

I just leaked my 383 this weekend and 7 holes were 2-3%, while #3 was at 5%. Problem? Seems minor, but....

Thanks

awkwardjeff
Member
posted June 12, 2002 03:32 PM
the amount of leakage is depending on a lot of things.....such as rings, machine work, valves, gaskets...........were was the extra leaking going??? out the exhaust valve? intake valve? past the rings into the pan? when you leak a motor you should remove the headers, carb, and radiator cap.......along with all the spark plugs......then you can see and hear where the air is going.

also if you didn't leak the motor down when new you have nothing to compare the latest tests too.........I don't think 5 percent is a big deal.........as long as it's going past the rings and into the pan......if it comes out the intake or exhaust I would pull that head and have a valve job done....if when leaking a cylinder you find air bubbles in the radiator I would remove that head and check for cracks, if everything is okay I would re-install with new head gaskets......

quote:
Originally posted by istock59:
What's an acceptable % of leakdown on a race engine?

I just leaked my 383 this weekend and 7 holes were 2-3%, while #3 was at 5%. Problem? Seems minor, but....

Thanks




Back to the Archives