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Broke_Ass_Nova_Turbo
20-01-04, 03:25 PM
Hello,

Having just replaced one dead engine in my 1.6 8V turbo, it appears we may have another engine in a bad way. Upon start up there is significant pressure from the rocker cover breather, included in this pressure is a qty of oil. The qty of oil increases as the engine runs and warms up. So much so that you can see the oil vapour [blue/white] coming from the breather.

This is a crankcase pressure problem and is clearly causing the oil to blow out of the breather system. So we got round to compression testing the engine. Remember 1.6 Turbo, Garett T3, Custom stainless 1 1/2" manifold, oil take off from rear oil gallery, return to modified sump. There is no spacer plate or lowered compression ratio, it uses

From Cam-belt [1] end to Dizzy end [4] *****DRY TEST*****
CYL 1 200
CYL 2 155
CYL 3 122
CYL 4 142

The wet test was approx 20PSI higher. This may indicate worn valve seats or guides, however, we are seeing no loss of vaccum at idle - the boost gauge is reading 15 in Hg. Does anyone have any idea as to what could be the problem.

Thanks

Dave

CP
20-01-04, 10:49 PM
From what you have written it appears to be worn rings - bottom end is probably tired. Not good news I'm afraid :(

NovaNeil
21-01-04, 12:40 PM
One or more of your Land rings have gone mate! (The ring of metal on your piston between the two piston rings). Its happened to me three bl00dy times!!! :evil: Sounds like you've been detonating and im not surprised with no Lowered compression!!!

Broke_Ass_Nova_Turbo
22-01-04, 05:41 PM
Cheers guys,

I think we are going to get an engine builders to take a look and sort the head and bottom end, freshen it up, and then install a copper head gasket.

Anyone got any idea how thick the copper head gasket needs to be to drop the compression to around 8.5-9 : 1

Cheers

Dave