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Compression Test 850Cc Engine


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#1 gazza82

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Posted 06 November 2019 - 12:45 PM

What would be a good reading or it is more they should all be roughly equal?

 

TIA



#2 slidehammer

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Posted 06 November 2019 - 01:21 PM

My compression tester shows 100 - 140psi as green. I think if you are around 90psi that would be ok. They need to be roughly equal.



#3 unburntfuelinthemorning

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Posted 06 November 2019 - 01:48 PM

Yes roughly equal.  I'd like to see more like 150 psi.  Test with throttle wide open and with engine warm if possible.


Edited by unburntfuelinthemorning, 06 November 2019 - 01:49 PM.


#4 gazza82

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Posted 06 November 2019 - 02:05 PM

115 and fairly close across all cylinders (not my engine).

It's a low compression unit from a late A35 van!

#5 nicklouse

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Posted 06 November 2019 - 02:11 PM

again it depends on many this the first is how you do the test. plugs out. throttle open. check and write down reading front to back and then back to front. and average. this is to compensate for battery drain.



#6 gazza82

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Posted 06 November 2019 - 02:15 PM

Thanks gents .. your pearls of wisdom will be passed onto the owner ... I know he didn't do the first attempt with the throttle open wide .. but it was with no plugs. I've seen all four as he was looking for comments on those too! 

 

His engine is using oil but from the comments he's left .. sounds like most is keeping the underside rust free! :D






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