Leak down tester

AbsoluteSpeed

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#1
Hey all. I have recently pulled my M7GE and will be freshing it up with new gaskets and valve steam seals.

I would like to do a leak down test before tearing it appart. Just curious what are acceptable numbers on these engines?

Also, what tester should i get?
I am looking to spend around $100. I have found prices between $40 to $250 but the reviews have not been super helpful. So any personal experience would be appreciated.
Thanks.
 

hvyman

Dang Dude! No Way Man.
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#2
you want like 5-10% leakage max. a healthy engine is usually 2-5%. if air comes out the radiator cap then hg is blown.

I have a snap on one so not sure about the others, but like a otc one should be fine. any really should be ok.
 

AbsoluteSpeed

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#5
Thanks for the replies. I ended up getting the ProForm leak down tester because it was available locally.

It worked well but it revealed a bit of an issue. All seemed ok until....

Cyl 1 = 7%
Cyl 2 = 12%
Cyl 3 = 12%
Cyl 4 = 60%
Cyl 5 = 8%
Cyl 6 = 12%

There was a noticable amount of air coming out of the exhaust port on cylinder #4
Sooooo it looks like I have a burnt valve or something. Guess I will be rebuilding the head.