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Guys,

Obtained a compression test on the car today.

Results as follows, from cylinder 1 to 6

170

169

170

155

150

155

Does this sound like an issue?

The motor is as smooth as silk.

Does anyone know where I can get hold of a mechanic whos mobile, and can do a leak down test, which is the next step.

Many thanks.

Jim

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  • 3 weeks later...

Hey there, your comps are just outside the limits specified by nissan, the only good thing is that they are 150 and above(showing that it hasen

t been thrashed). but seeing how they get lower from 1 to 6 usually indicates that its overheated at some stage and has slighty warped the head (no biggy,just a machine when head gasket gets done). 1 thing i would do also is do a tk head check test. which is a liquid that sits in a bottle that mix's with the fumes from the radiator, this will tell you if the head gasket is on its way out, good for pre purchase inspections.

I dont know everything, this is just things ive been through/seen before.

From vague memory, I believe no more than 10psi difference between highest and lowest value indicates a healthy engine (or was it ajoining cylinder I don't know)..

The R34 service manual specifies the following;

Compression pressure

175 psi standard

130 psi limit minimum

15 psi max limit of variation between cylinders

Looks like you are fine with minimum pressure and but below the limit for 15 psi cylinder variation.

  • 2 weeks later...
The R34 service manual specifies the following;

Compression pressure

175 psi standard

130 psi limit minimum

15 psi max limit of variation between cylinders

Looks like you are fine with minimum pressure and but below the limit for 15 psi cylinder variation.

Many thanks RS4 and others.

The car is sold, and the new one is pictured.

Regards

Jim

post-55447-1231104928_thumb.jpg

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