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FlipKing
08-01-2009, 08:53 PM
Dry test: cylinders 1-4 175,165,152,152
Wet test: 190, 185, 183, 176

whats the maximum variance between wet and dry allowed before it points to piston rings?

THoughts on burning a quart in 2-3 miles?


1995 1.8l miata. 100k miles
Init2winit
08-01-2009, 08:57 PM
Were those done hot or cold? Did you mean, burning a quart in 2 miles or 2000 miles? You have almost 20 psi difference between some, which is a little beyond normal. But, if your valve adjustment isn't the same between all of the cylinders, it will change your compression readings.

One quart in 2000 miles isn't terribly bad, but I have seen much better. What are the details on the engine?
FlipKing
08-01-2009, 09:04 PM
no, 2 miles, but I kept it under 4k and burned almost none. 100k miles. 1.8l miata
FlipKing
08-01-2009, 09:04 PM
it was driven to my house, let sit 20 minutes and then tested
Init2winit
08-01-2009, 09:32 PM
Burned a quart in 2 miles? Time to find another engine!
FlipKing
08-01-2009, 09:36 PM
well maybe I didnt notice it burning, but I added a quart today. It doesnt smoke at ALL if I'm under 4k or so. and my compression wasnt that bad which confuses me
FlipKing
08-01-2009, 09:57 PM
my thoughts are rings, headgasket, or valve seals. One person recomended an oil control ring too. so idk...the compression test seems to point to rings because wet was higher than dry
Barefoot
08-02-2009, 09:37 AM
my thoughts are rings, headgasket, or valve seals. One person recomended an oil control ring too. so idk...the compression test seems to point to rings because wet was higher than drywith a 100k on the motor the wet test will always give better results. standard compression pressure is 182 psi with a minimum of 128 psi. Maximum variation between cylinders is 28 psi. you are real close to the max. im with Init2winit.
green91
08-02-2009, 09:56 AM
Ive had several motors apart that were consuming oil and had great compression test results. And on pretty much every one the oil control rings were seized.
CaTcH22
08-02-2009, 10:40 AM
Ive had several motors apart that were consuming oil and had great compression test results. And on pretty much every one the oil control rings were seized.
x2. Oil ring is prolly seized to the piston. Just had an engine with the same syptoms that had a nearly perfect comp test.
Tech5
08-02-2009, 10:48 AM
x2. Oil ring is prolly seized to the piston. Just had an engine with the same syptoms that had a nearly perfect comp test.

reason being is that under light load its fine but when you builb more compression under heavy load that is where you get blow by...


Motor is fine just needs new rings

pop them outquick hone/clean and your good to go..get OEM for that car too, those aftermarket Cheap O 's are GARBAGE!!!
FlipKing
08-02-2009, 12:08 PM
alright, thanks guys, i'll talk to my mechanic
Meatball546
08-03-2009, 05:23 PM
If you have something like a crankcase vent valve, they have been known to fail and burn through much of the engine's oil in short order. That sounds like too much oil to be the piston rings.