Bore scoring

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Hurricane1500
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Bore scoring

Post by Hurricane1500 »

Hi quick question


If I have good compression in my engine could I still have bore scoring

Have an issue with oil consumption


Thanks
JasonGibson
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Re: Bore scoring

Post by JasonGibson »

got any details of what car it is ?

Amount of oil used and what grade of oil used
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Paul Mabley
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Re: Bore scoring

Post by Paul Mabley »

My 996 had a ferocious apetite for oil, I did 80,000 miles in it without issue whilst this was going on (1l every 1000 miles or less) but this was well within tolerance. My 997 was slightly better at 1500 miles, may be the way they were driven :lol:

I changed to thicker Mobil oil in the 996 it made a slight difference but not massive.

The air oil separator is a good place to start if smoking a bit. I did two DIY, awful 8 hour job but part relatively cheap at £60, they drop the engine in the workshops but charge a good amount for it!
Paul Mabley
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Hurricane1500
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Re: Bore scoring

Post by Hurricane1500 »

Cars a 2003 996 with about 70k on the clock

Using about 1Lt per 600 to 800 miles

sometimes smells a bit of burnt oil

Currently filled with 5-30 liqui moly but oil consumpsion was just as high with mobile 1

had the compresion checked all ok
Paul Mabley
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Re: Bore scoring

Post by Paul Mabley »

You should be OK for bore scoring then, check out the air oil separator.

Info here:

http://www.pelicanparts.com/techarticle ... arator.htm
Paul Mabley
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Brett928S2
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Re: Bore scoring

Post by Brett928S2 »

Hi :)

I have one of these on my 928 >>> http://m.diytrade.com/m4/pd/10892663/Pr ... 70550.html

Its an EXTERNAL seperator...and works VERY VERY well.... my Nitrous system creates extreme oil blowback and this almost cured it...and no stripping down the engine...30 min job to fit, assuming you can get access to an oil breather pipe...

All the best Brett :)
928S2 AUTO V8 4.7 1986-XPIPES ANDERSON RACE EXHAUST,K&N, WIZARDS OF NOS MAXX RACE CONTROLLER & WON RACE REVO NITROUS KIT 2000 HP CAPABLE.
-UK 928 1/4 Mile and Top Speed Record Holder-208.10 mph- Email managingdirector@pchealthcare.co.uk
R_D_Olivaw
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Re: Bore scoring

Post by R_D_Olivaw »

I had a similar issue on my 968, and thought the same, but it turned out to be worn piston rings. For me the problem started after a top end rebuild following a head gasket failure.
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Re: Bore scoring

Post by Paul Mabley »

R_D_Olivaw wrote:I had a similar issue on my 968, and thought the same, but it turned out to be worn piston rings. For me the problem started after a top end rebuild following a head gasket failure.
Shouldn't be, he said he has good compression.
Paul Mabley
Thames Valley Region

2013 Panamera Platinum Diesel, White
Sold April 2013 2009 997 C2S Gen2, Arctic Silver
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R_D_Olivaw
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Re: Bore scoring

Post by R_D_Olivaw »

Mine had good compression too when first tested, but it was explained to me that you can get leakage over time. When checked later they found air getting past thecylinders.

Maybe worth double checking.
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Rob996
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Re: Bore scoring

Post by Rob996 »

Hurricane1500 wrote:sometimes smells a bit of burnt oil
Could the burnt oil smell be a small leak cooking on the engine somewhere? - I know mine suffers from that! (and then there are the random smells you get when it is damp and the exhaust cooks whatever gets thrown at it!)
Rob

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Paul Mabley
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Re: Bore scoring

Post by Paul Mabley »

The car will smell a bit like that after a good run
Mine had good compression too when first tested, but it was explained to me that you can get leakage over time. When checked later they found air getting past thecylinders.

Maybe worth double checking.
Fair enough, I didn't realise that was a possibility, may be worth doing some more tests over a period of time to assess any trends.
Paul Mabley
Thames Valley Region

2013 Panamera Platinum Diesel, White
Sold April 2013 2009 997 C2S Gen2, Arctic Silver
Sold Aug 2010 2002 996 Carrera, Polar Silver
Sold May 2004 2003 Boxster S, Seal Grey
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