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Old 08-08-2009, 03:40 AM   #1
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Default How to tell if the rings are bad?

I have the head off the car right now and was wondering is there a way yo yell if the rings are bad without pulling the pistons out?
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Old 08-08-2009, 03:57 AM   #2
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Leakdown test, after you put the head back on.
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Old 08-08-2009, 04:01 AM   #3
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Quote:
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Leakdown test, after you put the head back on.
i actually did a leak down test before and the air only came from the oil filler cap. No air from exhaust, intake, dipstick, or radiator. anyway to measure the rings with a feeler gauge?
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Old 08-08-2009, 04:11 AM   #4
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...no.
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Old 08-08-2009, 04:49 AM   #5
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Quote:
Originally Posted by Rushin View Post
i actually did a leak down test before and the air only came from the oil filler cap. No air from exhaust, intake, dipstick, or radiator. anyway to measure the rings with a feeler gauge?
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Old 08-08-2009, 05:16 AM   #6
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if you were able to stick a feeler gauge between the pistons and the engine block at all, the engine would probably need a tear down. No way to tell unless you pull them out. If you were just going to pull them out, might as well tear the whole thing down and upgrade.
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Old 08-08-2009, 09:05 AM   #7
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Quote:
Originally Posted by Rushin View Post
i actually did a leak down test before and the air only came from the oil filler cap. No air from exhaust, intake, dipstick, or radiator. anyway to measure the rings with a feeler gauge?
What did the compression look like? Air from the oil filler would indicate bad rings if your compression was shot.
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Old 08-08-2009, 12:10 PM   #8
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The compresson was not bad. For some reason it was 205 in all cylinders except the third one, that was 175. Oil in the cylinders brought the compression up in all the cylinders an even amount. The problem is that I want to upgrade but I don't have $1500 to spend on pistons, rods, rings and everything else that goes with building an engine. So I am hoping that my smoking problem was from a bad HG and valve seals. The smoke was mostly white but smelled like oil and would only be there when I shifted at higher rpm or reved the car high.
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Old 08-08-2009, 12:15 PM   #9
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Rods, bearings and rings should only run you about $800 or so, if not a bit less.
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Old 08-08-2009, 01:10 PM   #10
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Bearings are another 100, plus shaving the block, boring out, and I bet a bunch of other little things will be over a grand.
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Old 08-08-2009, 01:23 PM   #11
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Well you don't know if it needs any of that stuff until its apart.
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Old 08-08-2009, 01:45 PM   #12
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If dry compression is so-so and wet is good, it's the rings.
So... you decide: bare minimum rebuild or full out with rods, pistons, etc.
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Old 08-08-2009, 02:57 PM   #13
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I guess what I am going to do is assemble everything back with my fresh head and new stock headgasket and my used arp studs. If most of the smoke is gone I am going to drive the car till the snow is on the ground and then rebuild the engine with forged pistons and rods over the winter.
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