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Old 07-29-2012, 10:26 PM   #21
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akazero- yes it is a open air bov, and I see what you're getting at, maybe I need to recirculate. good point.
krissetsfire- The previous owner just rebuilt the bottom end before blowing the turbo and says the compression is perfect. I would like to verify that though, because craigslist is anarchy. and I'm not going to turn up the boost. I was just a little frustrated when I typed that because I was hoping this thing to be at least fast-ish.
I tracked one of the oil leaks to the bov, so I pulled some boost pipes and found a shocking amount of oil inside. I'm fairly sure its just leftover from the turbo blowing; I've only driven it 8 miles since rebuilding the turbo. But on my valve cover where I would expect there to be a breather, it is vented to my intake pipe right before my turbo. I found a good amount of oil in that pipe too, and thats before the turbo. again, it could be leftover oil, but why is that vented that way? seems questionable, and like a potential source of oil going into the boost pipes to me.
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Old 07-29-2012, 10:58 PM   #22
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sooo if the rings didn't seat during rebuild or it wans't done well you could have a lot of blowby. i'd test compression but i'd check the leak down. it'll tell you your heads condition as well.

oil from the breather valve would indicate blowby to me i hope it's not!

unless you are racing or putting your motor under extreme pressure little to no oil should make it through there. it's just to relieve pressure.
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Old 07-30-2012, 12:44 AM   #23
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Quote:
Originally Posted by bloodnstuff View Post
on my valve cover where I would expect there to be a breather, it is vented to my intake pipe right before my turbo. I found a good amount of oil in that pipe too, and thats before the turbo. again, it could be leftover oil, but why is that vented that way? seems questionable, and like a potential source of oil going into the boost pipes to me.
I never figured out why companies design their turbo kits like this. Why would you want turbo inlet (vacuum) to pull crankcase vapor through your intake tract and back into your engine? I call this CGR (crankcase gas recirculation) because it reminds me of the same thing as EGR (exhaust gas recirculation). I understand the need for the crankcase to have vacuum assistance, but why plumb it to a turbo inlet?
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Old 07-30-2012, 07:11 PM   #24
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results of compression test:

dry wet
90 105
70 105
175 220
165 240

I'd really like to believe that its the the head, but with my luck, its rings. Although, the wet test helped on the good cylinders by roughly the same percentage as the bad. so maybe my luck has changed and its the head? or both? F, idk, im a shitty mechanic. either way, there is no easy way out of this one. opinions?
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Old 08-02-2012, 12:40 AM   #25
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Well, so far I have had two heads with bent valves and only one thrown rod. No piston blow-by to speak of. So from my stats head is much more likely....
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