Laydownthepwn

Hello.

I have.a 2000 supercharged Miata. It has just under 23k miles. I purchased the vehicle a few months ago and have been combating an issue with oil loss.

When under boost, the car blows a pretty good amount of oil out the breather tube. If I give it 5 or so good pulls, it needs about half a quart added. Car is running about 6psi btw.

A couple things I have tried. New pcv. Got an upgraded one from Fab9. No dice. Tried putting a crankcase breather filter on instead of routing back to the intake in hopes the boost was pulling too Much vacuum. Nope. I have a compression tester coming in the mail but am curious of there is anything else I can try? I installed a catch can a little while back and it is bone dry. After I get done driving there is some vapor in there but no oil. This oil is coming out the breather tube, not the pcv.

The car runs fine. Doesn't smoke. Pulls hard. I am kinda stumped. Any helps is appreciated!

Thanks!

Mudflap

Gonna need you to explain what you mean by the breather tube. You mention a catch can, but you need to carefully describe the setup.

TheScaryOne

iTrader: (3)

I assume with the breather filter it's just dumping all over the exhaust? Have you tried capping the PCV at the manifold to make sure its not pressurizing your crank case? If that fixes it a check valve inline might be a permanent fix.

Arca_ex

iTrader: (2)

Step 1 is making sure your PCV system is working and you're not feeding boost through the PCV valve etc, and if that is not screwed up then next step is a leak down test.

sixshooter

iTrader: (12)

Read the PCV thread sticky.

Laydownthepwn

Just wanted to follow up to my thread.

I read through the catch can thread, numerous breather system threads, and havent found the solution. I thought my issue might have been bad sealing on the valve cover baffles. I pulled those out, cleaned, and resealed. That did not seem to do the trick. The car still has LOTS of oil that comes out of the breather tube (driver's side of the valve cover). I did a compression test and read 180,150,150,180. Dont think it is bad rings. Any other suggestions? i am really out of ideas now.

sixshooter

iTrader: (12)

If you really want to solve the problem then you will throw the PCV valve in the trash, cap the intake manifold port, and route both sides of the valve cover to a breather can. This will actually solve your problem.

If you do not want to solve your problem then you may continue to attempt to use the PCV valve (which closes when you go into boost) and the undersized to vent hole on the hot side of the valve cover. This may require several iterations, modifications, undulations, gyrations, and exasperations before reaching a workable solution. That workable solution will either be a gigantic outlet on the hot side going to a breather (and opening up to all the passages twice their normal size inside the valve cover) or connecting both sides of the valve cover to the breather has I mentioned in the previous paragraph.

Your compression numbers have too much variation which is not the end of the world but may be contributing to your blow by issues. What sort of engine management are you using?

Laydownthepwn

Cool. Thanks for the insight. I am up for ditching the PCV if that will help things. Any suggestions on which breather to get?

I bought the car with an old piggyback system installed. Should have an Adaptronic unit coming in the mail one day this week. But for now, it is running a super outdated EMS. It is a SDS EMS-3 to be specific.

sixshooter

iTrader: (12)

I'm using an Allstar breather tank but there are a dozen good choices with internal baffles.

https://www.summitracing.com/parts/a...SABEgJGDvD_BwE

Laydownthepwn

one more update on this thread. I did what you said with the breather can, and by god it worked. thanks for all the help. you saved me a lot of frustration!

sixshooter

iTrader: (12)

I'm happy to help with this. It was a thorn in my side once upon a time as well.

I only wish everyone else listened... Sigh.