compression leak down

[bjones18]

I just did a compression leak down test on my 4G63:

1. 4% - slight hissing from crankcase
2. 6% - same
3. 12% - crankcase and exaust hissing
4. 4% - crankcase

Is this much variation normal? (the 12% number) or is something wrong with #3?

Bob

 

[DSMeclipse4G63]

the exhaust is from your valve no seating properly and will cause compression issues ad lack of power concern. hissing in the crank case is from blowby what year? Yes there is a problem with the rings or cylinder wall.
Andrew

 

[bjones18]

what percentage of leakage is to be expected? It has to go somewhere.

how much leakage do you get from correctly gapped rings at room temperature?

 

[DSMeclipse4G63]

I dont know the spec of the top of my head(Im at school) but Id be willing to bet that the 12% is from a bad exhaust valve(s) in cylinder 3. Usually if something happens to a ring the same thing will happend to the others as one cylinder isnt filtered from the others same exposure i.e. you run without a filter dirt will get in each cylinder not JUST cylinder 3.

Andrew