Testing compression...
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,255
Likes: 0
From: Manalapan FL
Testing compression...
I know there's more to testing compression than just fitting a compression guage in the cylinder. I believe there's some steps involved which includes squirting oil into the cylinder. What is the proper procedure and how to read the results? I'm having problems and not sure how to determine if it is related to rings, valves or a bad head gasket (or all three!).
Thanks in advance,
D. Ocean
Miami, FLA
Thanks in advance,
D. Ocean
Miami, FLA
Pro
Joined: Oct 2004
Posts: 663
Likes: 0
From: Honolulu Hawaii
[QUOTE=74FLCONV]I know there's more to testing compression than just fitting a compression guage in the cylinder. I believe there's some steps involved which includes squirting oil into the cylinder. What is the proper procedure and how to read the results? I'm having problems and not sure how to determine if it is related to rings, valves or a bad head gasket (or all three!).
Thanks in advance,
D. Ocean
Miami, FLA[/QUOTE
Make sure you record the first readings, all plugs removed and throttle blocked wide open with engine at normal temperature. compression should build up quickly on each cylinder, if low on first stroke then builds up shows signs of bad rings. if low on first stroke that doesn't build up shows signs of bad valves or head gasket. you need to put 3 squirts into each cylinder, if compression builds up after this, then you are looking at worn rings, if no change indicated, then it is either the valves or head gasket. I just did this on my 78 yesterday with good results. hope all goes well on yours
Thanks in advance,
D. Ocean
Miami, FLA[/QUOTE
Make sure you record the first readings, all plugs removed and throttle blocked wide open with engine at normal temperature. compression should build up quickly on each cylinder, if low on first stroke then builds up shows signs of bad rings. if low on first stroke that doesn't build up shows signs of bad valves or head gasket. you need to put 3 squirts into each cylinder, if compression builds up after this, then you are looking at worn rings, if no change indicated, then it is either the valves or head gasket. I just did this on my 78 yesterday with good results. hope all goes well on yours
Thread Starter
Melting Slicks
Joined: Oct 2002
Posts: 3,255
Likes: 0
From: Manalapan FL
[QUOTE=c3 in hawaii]
That's what I was looking for.
Thanks!
D. Ocean
Miami, FLA
Originally Posted by 74FLCONV
Make sure you record the first readings, all plugs removed and throttle blocked wide open with engine at normal temperature. compression should build up quickly on each cylinder, if low on first stroke then builds up shows signs of bad rings. if low on first stroke that doesn't build up shows signs of bad valves or head gasket. you need to put 3 squirts into each cylinder, if compression builds up after this, then you are looking at worn rings, if no change indicated, then it is either the valves or head gasket. I just did this on my 78 yesterday with good results. hope all goes well on yours
That's what I was looking for.
Thanks!
D. Ocean
Miami, FLA
