engine compression test specs?

mazdaguy20 · 02-20-2008, 06:46 PM

my compression was 125psi on the back two cylinders and 115psi in the front does that mean i should junk it or what the reason i checked is because its blowing blue but only when i start it up and then drive for a lil bit and its gone can someone please answer some question i looked all over the internet for specs but there is nonthying that would be greatly apreciated thank you

z07 · 02-20-2008, 07:24 PM

Pull the plugs and add one table spoon full of STP or some thick oil like 20w-50 to each cylinder via the spark plug hole. Then re-test the compression. If the values remain the same you have top end IE valve/valve seat issues. If the values rise then you have worn rings/cylinder walls.

A NAPA machine shop (and others of course) should be able to rework the head for about $250ish.

02-20-2008, 06:46 PM	#1
mazdaguy20 Junior Member Join Date: Feb 2008 Posts: 1	engine compression test specs? my compression was 125psi on the back two cylinders and 115psi in the front does that mean i should junk it or what the reason i checked is because its blowing blue but only when i start it up and then drive for a lil bit and its gone can someone please answer some question i looked all over the internet for specs but there is nonthying that would be greatly apreciated thank you

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02-20-2008, 07:24 PM	#2
z07 Senior Member Join Date: Feb 2008 Posts: 391	Pull the plugs and add one table spoon full of STP or some thick oil like 20w-50 to each cylinder via the spark plug hole. Then re-test the compression. If the values remain the same you have top end IE valve/valve seat issues. If the values rise then you have worn rings/cylinder walls. A NAPA machine shop (and others of course) should be able to rework the head for about $250ish.