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Got hold of a compression tester from COS, did the test on the Z and here are the results.

 

compression.jpg

 

So my Right Bank is screwed!

 

What is the next course of action? Can anybody suggest what might cause this?

 

:cry: :shock:

 

Gutted....

Featured Replies

Cylinder leakage test next mate to find out where all the compression is leaking to.

 

If it's a whole bank I would say it'a gonnabe a head gasket problem, however saying then my money is still on your valves.

  • Author

What would a wet Compression test tell me mate? I only did a dry test.

 

Would one point more to the valves?

wet compression using oil would tell you if the air was leaking past the pistons, but on the low compression rates you are showing it may not show a great deal.

 

You need to do a cylinder leakage test. You fill the cylinder with X amount of psi. Then monitor where it's leaking to.

 

1) adjacent cyliner = head gasket

2) zorst or plenum (removing the balance bar is much easier) = valves

3) oil bubbles = pistons

4) water res = head gasket

  • Author
wet compression using oil would tell you if the air was leaking past the pistons, but on the low compression rates you are showing it may not show a great deal.

 

You need to do a cylinder leakage test. You fill the cylinder with X amount of psi. Then monitor where it's leaking to.

 

1) adjacent cyliner = head gasket

2) zorst or plenum (removing the balance bar is much easier) = valves

3) oil bubbles = pistons

4) water res = head gasket

 

Any clues how to do this mate? Do i have to remove the plenum? Sorry, bit thick when it comes to compression tests!

no mate, you need to get your car to a garage who has a cylinder leakage test or find somone on here who has one. You basically blow air into the cylinder via the spark plug hole.

Are you losing any water? Have you drained the water and see if it what colour it is. If you are not losing any water and the water looks like water and not brown sludge, I doubt it is the head gasket.

  • Author

No but i will do tomorrow mate, taking the plnum off and the Pas Side rocker cover to take a look at valves, someone suggested this to me.

you wont see much of the valves just by taking off the rocker cover, you really need to take off the head to inspect them properly. Do the cylinder leakage test first, save yourself unnescary work.

Are you losing any water? Have you drained the water and see if it what colour it is. If you are not losing any water and the water looks like water and not brown sludge, I doubt it is the head gasket.

 

HG on me first Z went with no symptoms aside from pressurising - so that's not a definite test. Remember I just had weird occasional overheating for ages and no other symptoms, and couldn't work out what it was?

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