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manual doesn't provide targets or ranges for compression tests. anybody know what would be the range for a healthy engine?
 

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yes, but what's the translation to psi for reading off the gauge?
 

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disregard. I found the calculation, thanks.
 

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350psi plus. 340ish is the min to get diesel to combust
hmm. at 29.96 in and 19.5 ratio, the calculation came out to 286 psi. the shop that has my truck did a compression test on mine, and it came back 250-290 psi on all cylinders. and the truck drives fine (albeit that pesky turbo seal that failed after being rebuilt in Feb. ).

I'm assuming the calculation and test were not done correctly?

29.96in=14.71 psi

(14.71*19.5)/1 = 286.84psi
 

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shop thinks it was the compression gauge. they had trouble with the quick disconnect so assume reading were off. where did I go wrong in the calculation though?
 

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If it's of any value I just did a compression test on my 200tdi and I have 460 to 480 across the cylinders with cold engine. I bought a $39 tester on harbor freight that I tested withy air compressor at 150psi and it reads fine. First pump is 160 to 180 on all 4. I put a few squirts of oil in number 1 cylinder and it read 500psi. We tested just one cylinder on my son's 2.5 NA hot and it reads 500. Isn't all this too high?
 

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350 psi min. Also important that they should all be very close to the same across all cyl.

------ Follow up post added August 1st, 2015 07:32 AM ------

Never had one suffer from too high a compression…..unless it had water in it.
 

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350 psi min. Also important that they should all be very close to the same across all cyl.

------ Follow up post added August 1st, 2015 07:32 AM ------

Never had one suffer from too high a compression…..unless it had water in it.
Great than!
 
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