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-   -   Oil out of Breather and tailpipe (https://www.miataturbo.net/engine-performance-56/oil-out-breather-tailpipe-79783/)

wolfram 06-30-2014 09:25 AM

Oil out of Breather and tailpipe
 
I found a few other posts here that are similar to my symptoms, but not quite the same, so I thought i'd open a new thread.

I have a fresh rebuilt 1.6 (new forged rods, rings, turbo rebuild kit, new head, new oil pump). I have oil splattering out of my breather (and yes i have replaced the PCV). I noticed some smoke only after about 12psi and shortly after during the engine braking after above 12psi. When I parked, I opened the hood and saw oil splatter around the breather filter off the driver side valve cover. I am debating installing an oil catch, but wanted to check what was wrong with this first. Any thoughts?

Miater 06-30-2014 02:39 PM

How many miles on the rebuild?

How were the rings setup? End gap and position in relation to one another.

How is the PCV setup? Filter on one side, other side goes to intake with check valve?

Do you have a vacuum gauge?

wolfram 06-30-2014 02:57 PM

The two top compression rings were set 90deg off from each other and the oil ring was another 90deg off of the bottom of those two. Only about 500 miles on the engine, broke it in as normal (lots of engine braking at high rpm) and changed the oil at 25miles, 50, 100, 200, 500 (just changed it). Vaccuum looks good at idle, and overall the engine runs good and strong, just odd that i have positive crank pressure enough to blow out the breather filter on the valve cover.

wolfram 06-30-2014 02:58 PM

Also, I'll run another compression test, but i tested it about 100 miles ago and the were all in the 150psi range +/- 5psi or so. Would a leak down be a good test for these symptoms?

wolfram 06-30-2014 04:27 PM

The more i think about it, it seems to be building boost a little slower than before the rebuild. Also, idle seems to have the same vacuum, however i have noticed that at cruise, it seems to be less vacuum and around 10-15% throttle, it wants to go to 0 vacuum (0 boost).

What are the chances my exhaust cam is off one tooth? could this be part of the positive crankcase pressure issue, as well as the slower boost ramp? Seems to run well, so thats why it was hard for me to believe being off a bit that it would still rev up to 6500 and feel sound pretty good. Does seem that it could be a bit off by the way it feels, but is that even possible at this point?

wolfram 06-30-2014 04:35 PM

Also, it may not be a function of boost pressure like i said above (over 12psi), it could just be a function of RPM since they both will be increasing with RPM. I dont really see less than 12psi above 4,800 RPM anyway...


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