performing leakdown test

[Stock4AG]

Can someone refresh my memory on how to do a leakdown test?
I have a tester but havn't done one for years.
I remember using a stick or straw to find the highest point of each piston, then thread in the tester. The cams should be at the rounded side of the lobe and valves are more or less closed around that rotation?

Does it matter it is compression or exhaust stroke?

Thanks in advance.

[LynchburgCSI]

Youtube: Eric the car guy. I think he covers it with the compression test.

[RichardDrone]

I have the instructions from my old Snap-on leak down tester. If you still need them I can scan them and then post. Let me know Richard

[pbr333]

Low pressure leak-down test most accurate at determining cylinder wear....100% in and ??%
out=amount of wear/leakage. For the track you want around 5%or less(fresh/new) ,but as a DD you can have as much as 28%(high mileage,O/H time).
Just screw your adapter in the spark plug hole, turn engine untill your cams for that cylinder are up(rabbit ears/top dead center), connect tester to air compresser , zero guage ,plug in adapter and read.Guage will read % of leakage.
That's for the single guage tool RichardDrone is refering to.
Also a very valuable tool for diagnosing engines.

pbr