leakdown test bad, what should I do? - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

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Old 01-10-2008, 05:10 PM   #21
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I had some blow by, but almost no oil consumption. I've always tuned with less than ideal piggybacks and it made it a little harder, but that was mostly due to low compression. I wouldn't think it would be a big deal, because boost is boost. Low compression is really the problem.

High oil consumption will gum things up and kill them more quickly. That worries me a bit.

Did you have the leakdown test done at a shop or did you do it yourself and what were the actual numbers? Was the engine warm or cold? Is your exhaust very blue? (it seems strange that you would burn so much oil with such good compression)
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Old 01-11-2008, 02:05 PM   #22
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I did the leakdown test myself, warm engine. I did not record the numbers because at 150psi, air was hissing rapidly out of the dipstick tube when testing each of the cylinders. I just figured the rings were toast.

Should I redo the test and look for something else? I didn't hear any air coming from the exhaust or intake or adjacent cylinders. But this doesn't rule out bad valve guides/seals contributing to the consumption, right?

The exhaust is significant in quantity and blue in color but only above 4k rpm. Nothing visible at low rpm. Bumper gets oily soot in less than 100 miles.

Thanks again.
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Old 01-11-2008, 02:16 PM   #23
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Quote:
Originally Posted by xveganxcowboyx View Post
(it seems strange that you would burn so much oil with such good compression)
The oil control rings are worn and allowing excess oil on the compression rings, keeping them sealed up with oil, despite their worn conditions.
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Old 01-11-2008, 05:27 PM   #24
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Originally Posted by patsmx5 View Post
The oil control rings are worn and allowing excess oil on the compression rings, keeping them sealed up with oil, despite their worn conditions.


Good diagnosis.



No idea what your best option is on this one, sorry. Oil consumption that high is pretty scary though.
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Old 01-26-2008, 11:57 PM   #25
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Dude, you are looking too much into it. So long as the engine doesn't misfire or burn too much oil you will be ok. Yea, you might not make that last 5% of power over a fresh engine, but learn with the beater engine while saving up the bucks for your "good" engine.

Throw the turbo on your engine!
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Old 01-27-2008, 01:33 AM   #26
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Originally Posted by mrtonyg View Post
Dude, you are looking too much into it. So long as the engine doesn't misfire or burn too much oil you will be ok. Yea, you might not make that last 5% of power over a fresh engine, but learn with the beater engine while saving up the bucks for your "good" engine.

Throw the turbo on your engine!
+1. My engine burns alittle oil, and only did ok on the compression test. Its been about 5 months of up to 10 psi of boost, doing great.
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Old 01-27-2008, 02:04 AM   #27
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Originally Posted by Arkmage View Post
that engine restore crap in a silver can seemed to work great on my buddies old school trooper. stopped the oil consumption for nearly 40K miles when it spun a bearing (275K when it died).
I just got an $8 can of the "engine restore crap" and, just for the hell of it, I filled it up with Havoline High Mileage 10w-30 (on sale for $0.99/qt). I suspect both products are snake oil... but I'll report back with the results after 500 miles or so.
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Old 01-27-2008, 02:22 AM   #28
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Quote:
Originally Posted by chucker View Post
I just got an $8 can of the "engine restore crap" and, just for the hell of it, I filled it up with Havoline High Mileage 10w-30 (on sale for $0.99/qt). I suspect both products are snake oil... but I'll report back with the results after 500 miles or so.
I've used engine restorer on several vehicles with good results. My 86' trooper had 140 pounds of compression on all 4 cylinders, front and rear main seals leaked, and smoked a little. I ran engine restorer for 3K miles and it stopped leaking oil, stopped smoking, and last compression test yielded 185 on all 4 cylinders. Not to bad for 8 dollars.
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