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 Post subject: Piston rings or valve guides?
PostPosted: Wed Mar 04, 2015 4:48 pm 
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Location: The little old town of East Grinstead, UK
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For all the time I have owned my 944, I have had this problem, but it has been ignored due to more important problems such as brakes, fluid leaks, and belts etc.

Under hard acceleration and high revs, I can smell hot oil, and if I rev it high enough it emits a cloud of oily smoke from the exhaust. It was quite embarrassing on a motorway once when I floored in 3rd gear up to the limiter and blinded the car behind me.

All I know is that it could be piston rings or valve guides. What can I do to find out?

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 Post subject: Re: Piston rings or valve guides?
PostPosted: Wed Mar 04, 2015 7:27 pm 
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Joined: Mon Nov 05, 2007 3:15 pm
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Location: BOURNEMOUTH
Hi Alex :)

You get a WET and DRY compression test done....

I.E. with (wet) and without a couple of squirts of oil in each plug hole....

IF the wet test is higher its rings...if no difference its guides.....

All the best Brett :)

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 Post subject: Re: Piston rings or valve guides?
PostPosted: Wed Mar 04, 2015 8:00 pm 
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Location: Warwickshire
To avoid any question as to what the issue could be I would personally look into getting a leakdown test. That will tell you for sure what is up with the car.

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 Post subject: Re: Piston rings or valve guides?
PostPosted: Thu Mar 05, 2015 9:39 pm 
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Superb help. I shall do as suggested.

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Alex.
'85 944 mostly working
'83 924 "Yin Yang" cheap track car with another member
'01 Vauxhall Combo diesel van for camping, working, and moving slowly

Computer Problems: At your WITS End? http://www.witscomputers.co.uk


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 Post subject: Re: Piston rings or valve guides?
PostPosted: Fri Mar 13, 2015 11:00 am 
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Location: Wolverhampton - West Mids - UK
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If you dont have a lot of time, check your dipstick is still in the dipstick tube. If it keeps popping out, you have a ring problem - easy test.
Normally smoke on lift off is oil seals on the turbo or on NA it would be valve guide seals.
Yours is on the power, so its pointing to compression related oil (rings) or even HG.

Best results will be 1) Compression Test (dry+wet) and 2) Leakdown......already mentioned by Brett928S2 and AlpineTurbo


Let us know the results!

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 Post subject: Re: Piston rings or valve guides?
PostPosted: Sat Mar 14, 2015 12:55 pm 
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Joined: Wed Oct 26, 2011 6:40 pm
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Location: The little old town of East Grinstead, UK
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indyz12 wrote:
If you dont have a lot of time, check your dipstick is still in the dipstick tube. If it keeps popping out, you have a ring problem - easy test.
Normally smoke on lift off is oil seals on the turbo or on NA it would be valve guide seals.
Yours is on the power, so its pointing to compression related oil (rings) or even HG.

Best results will be 1) Compression Test (dry+wet) and 2) Leakdown......already mentioned by Brett928S2 and AlpineTurbo


Let us know the results!


It has also happened on lift off at high revs / full throttle. Dipstick stays put!

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Alex.
'85 944 mostly working
'83 924 "Yin Yang" cheap track car with another member
'01 Vauxhall Combo diesel van for camping, working, and moving slowly

Computer Problems: At your WITS End? http://www.witscomputers.co.uk


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 Post subject: Re: Piston rings or valve guides?
PostPosted: Sat Mar 14, 2015 1:09 pm 
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Joined: Sat Jan 25, 2014 7:22 pm
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Location: Wimborne
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My money's on rings I'm afraid ...

G

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