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 bigdave
Officially Full-On Dubber
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| posted on June 6th, 2011 at 06:56 PM |
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Ring gap for 85.5 standard bore?
What is the recommended piston ring gap or tolerance before it is time to throw away?
Cheers
dave
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grumble
Son of Jim - Creator of Good
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| posted on June 6th, 2011 at 07:17 PM |
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The recommended ring gap was .004" per inch of bore. Obviously if the bore is scored or lipped badly it is time to replace the units. When we are
rebuilding normally we replace the pistons and barrels, this is the same as reboring an inline motor.
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68AutoBug
A.k.a.: Lee Noonan
Aircooled Master
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| posted on June 6th, 2011 at 11:45 PM |
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| Quote: | Originally
posted by bigdave
What is the recommended piston ring gap or tolerance before it is time to throw away?
Cheers
dave
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Hi Dave,
I'm not an engine rebuilder but that is a strange request ...
it depends on the manufacturer of the rings I would say...
usually Pistons with new rings and cylinders are replaced all together...
check if there is a lip in the cylinder ...
where the rings don;t go -
this will be the original size of the cylinder...
You should be able to feel the lip with Your Finger...
cheers
LEE
- [size=4]Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY--- [/size]
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vwo60
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| posted on June 7th, 2011 at 01:08 PM |
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The ring gap is a major part of any engine build, you cannot trust any manufacturer , these need to be checked and filed to the correct gap when you
install any piston rings,
Compression ring clearance new - .3MM to .45MM.
Oil scrapper ring clearance new - .25MM to .4MM.
Wear limit compression ring - .9MM.
wear limit oil scrapper ring - .95MM.
sizes taken from the factory manual
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 matberry
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| posted on June 7th, 2011 at 08:50 PM |
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I recommend .0045"/inch of bore for our engines
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
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