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Lots of smoke, plus oil in intake manifold - bad oil control seals?

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Old 08-21-10, 05:05 PM
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Lots of smoke, plus oil in intake manifold - bad oil control seals?

I swapped a s4 j-spec motor into my car about 6 months ago. I finally got the standalone and other stuff fixed last month and have been driving it more, but it is smoking quite a lot. Thinking it was the turbo, I put on a brand new BNR stage 4. After putting it on, it is still smoking. Today I pulled the intake manifold to block off the oil injection system and do a few other things.

The first thing I noticed is that the rear secondary running is pitch black, the front secondary is darker than normal, and the primaries are pretty much clean. Also, the inside of the collection chamber for the secondary runners in the UIM is pitch black, and there is even a little bit of oil pooled at the bottom of it.

I'm pretty sure this means the oil control rings are shot, is that correct?
Old 08-21-10, 05:11 PM
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It smoke a little bit all the time, more under boost, and puts out a total smoke screen when I shift under boost - a massive cloud comes out when I let off the throttle, then mostly clears up when I get back on the gas.

Also, there is a weak side seal on the front rotor - I get about 95-95-60 compression.

My hypothesis is that the blowby from the weak side seal is pressurizing the oil system, causing it to leak out a weak oil control ring in the rear rotor. Sound reasonable?

Finally, I know it is a crapshoot to drop in a j-spec motor. I knew that going into it, but it had good compression so I wanted to get the haltech sorted first if at all possible - which I have done. I just want to make sure its not something else before I pull the motor.
Old 08-21-10, 06:02 PM
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If you have oil in the intake my first guess would be the turbo
Old 08-21-10, 06:14 PM
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Thats what I thought too, but I have freshly rebuilt turbo and it smokes like it did with the old turbo. Also, the old turbo didn't show any signs of leaking oil once I pulled it.
Old 08-22-10, 12:23 AM
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Are you running a pcv hose to the intake?


From what I remember, the only way oil will get inside the intake manifolds is either the turbo leaking oil (compressor or turbine side), pcv blowby, or the oil injectors on the LIM (though that doesnt explain oil in the UIM).
I might be missing something.

If the side seal is bad, it might also cause the oil control rings in the front rotor to go bad also and leak oil.
Old 08-22-10, 12:38 AM
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No, the nipples on the oil filler neck are vented to atmosphere - a catch can is on the to-do list.
Old 08-22-10, 08:57 AM
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Blowby sounds like a reasonable hypothesis. When an oil control ring starts to fail due to age/whatever, one of the most commons symptom is smoke as you pop the clutch in to shift.
Old 08-22-10, 10:29 AM
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If you have only one bad pulse on the rear rotor, then there must be a cracked or chipped side seal. I'd wager that is what is pressurizing your crankcase. At the same time, it will pollute the oil with fuel, making it thinner and thinner, causing more smoke.
Old 08-22-10, 11:31 AM
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After I got it running right and put on the new turbo I did the water treatment then changed the oil. After that the smoking got even worse, and my oil pressure was higher than before. I was hoping that I could get the side seal unstuck as a last resort, but I think it just removed some of the carbon that was helping it seal. Oh well. I got the haltech squared away which is the most important thing, plus I learned a hell of a lot about it while I've been tinkering with it.

Would it hurt it to drive it for another week or two like this? I need to get my other car into the shop to get aligned and balanced, plus I REALLY need to get the RX-7 into the shop to have a wheel bearing replaced.
Old 08-22-10, 12:09 PM
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It sounds like its a blow by problem. Now if you notice the blowby in your car is recirculated from the Oil fill tube and recirculated back before the turbo.
If you disconnect the hose and plug it at the intake to not have a vacuum leak you will blow oil out onto wherever the hose is pointing, you can tape a gatorade bottle so it doesnt spray everywhere and just check it form time to time. That will keep you from smoking as much.
The smoke you see when you let off the throttle is the oil pooled up int he manifold getting sucked in by the vacuum produced when you close the throttle plates.
Old 11-13-10, 12:31 PM
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i have a problem like this as well, i took turbo off (the turbo had been working before hand) and attached the maf on the the intercooler to see if it would still smoke and it did. so i know its not the turbine but i want to know if the problem is internally related or just something that not connected right. the car smokes like crazy as soon as its started up. its an s4 turbo streetport. its just been rebuilt and ive started the car 4 times. after the last start up i decided that enough was enough i took the engine out there was a huge pool of oil on the ground. i also noticed that there was a lot of oil accumulated on the uim and it poured out when i removed it... i also noticed that the brake booster vacume line that goes behind the mani had some oil in it... one og my oil meetering lines had broke when installing the rebuild but with the use of a heat gun it was "fixed" but even if this was an issue i highly doubt that the omp would smoke up the way this car would smoke...
Old 11-13-10, 12:32 PM
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heres the video of the amazing smoke


<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/YuG0ZV27hDo?fs=1&amp;hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/YuG0ZV27hDo?fs=1&amp;hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>
Old 11-13-10, 02:37 PM
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mine use to smoke, but i put motercroite oil i think that how u spell it
ill get the name later, but it stop all my smoking and fix alot stuff, u can give that a try bro
Old 11-13-10, 05:37 PM
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Its basically what I had originally though. Basically, it was caused by a bad oil control ring as best I could tell. I'm afraid thats what yours looks like - I can't think of something else that could cause it to smoke that bad other than a bad turbo oil seal. I am far from an expert, but thats what it looks like to me.
Old 11-13-10, 08:19 PM
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Originally Posted by Sideways7
Its basically what I had originally though. Basically, it was caused by a bad oil control ring as best I could tell. I'm afraid thats what yours looks like - I can't think of something else that could cause it to smoke that bad other than a bad turbo oil seal. I am far from an expert, but thats what it looks like to me.
thats what i had figured, i highly doubt it was the turbo, its a fresh rebuild with warranty and its going to get taken apart either way, i just want to know why it is that my UIM has oil in it? any ideas? will a plugged up oil injector make this king of oil excess? i also checked the intercooler for blow by and found none...so i highly doubt that its turbo related.....and since the motor has blown soo much oil into the turbo hot side, will that deteriorate the turbo heavily?
Old 11-13-10, 08:36 PM
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Mine had oil in the UIM as well. In fact, there was even oil as far up as the throttle body. I think it is due to the intake pulses going through the intake due to port openings and closes. I can't remember the specifics of it, but basically the force of the rotor closing the port pushes the air back through the intake. In fact, the NA engine actually makes about 1 PSI of boost due to this - Mazda called it dynamic supercharging. It threw me for a loop as well. I was convinced it was the turbo, and when I put on the BNR hybrid it was still smoking.
Old 11-14-10, 01:58 AM
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oh i see, very good info here
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