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GoGs_MacAulay
22nd July 2010, 16:13
done a compression test on my mates 2002 saxo vtr, 56.000 on the clocks, dry test read 75psi 75psi 75psi 75psi and wet test with a little oil down the spark plug holes read 150psi 150psi 150psi 150psi

could this be piston rings? he drove the car with a fucked radiator for about 10miles so the reason for the test was to see if the head gasket was fucked.

Any idears?

raunchz
22nd July 2010, 16:18
75psi across all four cylinders ?!

I'm no expert but that seems bloody low ! You using a screw in compression tester ?

GoGs_MacAulay
22nd July 2010, 16:25
yeah 75 psi across all four cylinders with a dry test, 150psi across all four cylinders with oil down the cylinders. yeah screw in compression tester!

saxo-parts
22nd July 2010, 16:30
its buggered, if its been overheated it sounds as though things have got hot in the bores and either rings have stuck or pistons have picked up on the bores

raunchz
22nd July 2010, 16:32
its buggered, if its been overheated it sounds as though things have got hot in the bores and either rings have stuck or pistons have picked up on the bores

+1 on it being buggered

75psi on a dry test is very low, and the fact that the compression reading doubles when a wet test is done isn't a good sign either.

I'd start looking for another engine

GoGs_MacAulay
22nd July 2010, 18:37
so the engine is buggered? no way of fixxin it?

saxo-parts
22nd July 2010, 18:56
yes, anything can be fixed at a cost and i'm afraid the parts needed to build a saxo engine properly out-weigh the costs of a good used low mileage engine by a factor of a gazillion per-cent

saxo_gash
22nd July 2010, 20:12
+1 aswell definatly not good new engine job bud

Stevo123
23rd July 2010, 13:01
You need to have throttle wide open when performing the tests, you did do that yeah?

It is strange to have exactly the same (75psi accross all 4) and wet 150psi? Is the guage to be trusted? Get a second opinion mate, 75 psi would be a very poorly engine, likley burning oil at a big rate,poor performance and economy etc.

AndySAXO
23rd July 2010, 14:17
Yer it werid that they are the same accross each bore,

But 75 is very low, so would think, maybe the ring are shot, due to the walls not getting cooled!

Juggyluggs
23rd July 2010, 14:26
just a question sorry to hijack but where can you get compression tests done at?

saxo-parts
23rd July 2010, 16:07
any garage or buy a compression tester and do it yourself