Leak down test

[Bentracin]

Does anyone have the proceedure to leak down test a Legend? How do you get the pistons in the right place by rotating the engine? I am used to doing this on a late model with a degreed balancer but not sure of the best way to turn over the FJ motor and get the pistons in the right location. Thanks.

[ducks13]

It has been a while but I believe I did it with the valve cover off.  There is a hex shaped section on the camshaft you can use to turn the engine.  Put it a close to TDC on the cylinder you want to check and hit it with the air.  If it doesn't move you did it, if it rotates either direction you need to turn it a little less, or more, until the piston stays on TDC with pressure in the cylinder.  

[kbbob]

Clean debris from spark plug area with compressed air, remove all spark plugs, rotate engine using the hex at the exlhaust cam. Rotate engine untill the exhaust and intake lobes are pointing away from each other. This will place the piston at TDC on the compression stroke. Record percent of leakage while listening for air flow at intake, exhaust and crankcase to determine source. A tight engine should be less than 4% leak down.

[IraceLegends77]

How many PSI do you apply? I do this everyday to aircraft engine with 80 psi but how much would you use on a Legends motor

[Gimpster]

Scott... 100 pounds is the standard on engine platforms within the power sports industry

~Gimp~