Vauxhall Zafira A - low compression in one cylinder

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Fri 6 Jul 2012 12:48
Vauxhall Zafira A - low compression in one cylinder - robotcat

Hi, I've just had a replacement engine fitted in my V reg Vaxhall Zafira. Garage who fitted it (but did not supply the engine) have just told me that it has low pressure in one cylinder. I've contacted the company that sold me the engine (with 3 months warranty) they tell me that it's probably a very simple problem and easy to fix (I have my doubts). What are the potential causes of this, am I being had by the seller of the engine or is there some simple cause to fixing this engine rather than taking it out and starting all over again/scrapping the Zafira? Obviously I will be fighting to get the company that sold me then engine to pay for repairs. Thankyou.

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Fri 6 Jul 2012 13:02
Vauxhall Zafira A - low compression in one cylinder - unthrottled

Potential causes of low compression:

Worn piston rings

Scored bore

Blown Head gasket

burnt exhaust valve(s)

Incomplete valve closure

Only the last one is 'simple'-and that assumes that the reason for the incomplete closure is a build up of carbon on the valve stem.

They don't want to pay for the labour of a replacement engine!

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Thu 12 Jul 2012 12:33
Vauxhall Zafira A - low compression in one cylinder - robotcat

Thanks for that. I've just been told by the garage that they will need to grind down the cylinder head in order to repair the engine. I'm assuming this is not good! Trying to decide now whether to cut my (significant) losses and scrap the car or to keep on spending to get it working.

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Thu 12 Jul 2012 13:05
Vauxhall Zafira A - low compression in one cylinder - unthrottled

I think they mean that the cylinder head needs to be skimmed-presumably because it overheated at some point and warped. A crushed head gasket was probably giving the low compression readings.

I don't envy your position. The labour to fit and then tear down the engine must be expensive.

The head skim isn't expensive (often done as a precautionary measure). Ask the garage if they can identify why the head needs 'grinding'. If the engine is fundamentally ok, it makes sense to press on and finish it.

Very bad luck BTW.

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Mon 16 Jul 2012 00:51
Vauxhall Zafira A - low compression in one cylinder - mccgarage
I can take the head off for £50 skim and pressure test for £80 and refit for £125 if your interested I'd advise a cam belt change swell another 80.00 for a decent kit this will include a oil and filter change do rucks of these engines ex vauxhall cw10 9lf 01606 215697 cheers Craig think that's 340 all in
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Thu 19 Jul 2012 03:18
Vauxhall Zafira A - low compression in one cylinder - 1litregolfeater

It'll be the rings gone, due to poor oil changes.

They are very thin and delicate.

If the bores are scored but not too bad I'd still go for a ring change and keep fingers crossed.

Depends on circumstances and who's doing it

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