Well the title says from the crankcase for a lack of a better word..so I used piston terminology. To everyone who remembers me, I have been at the regional training center for Toyota/Scion preparing for the launch of the new Tacoma. Needless to say I haven't been around here for a while.

My issue is smoke. The PO had put a breather filter on the oil filler neck. I have neglected to change it because of work, but plan on it. I don't see how it can be good as it allows moisture to enter. When I was looking under the hood and wrapped it up briefly, a small puff of smoke come from the filter. I shut it down about a minute later, pulled the dipstick and seen smoke come from there. It almost seems like homogenized fuel vapors similar to when you see when you remove a carburetor. I am concerned about this because I don't want anything bad happening to her. Although I am a master with piston engines, I readily admit I would not invest in undertaking the rebuild of the 13B myself. And more importantly, I would feel bad if something happened and I put a single turbo LS1 I have sitting around in her. I just can't do that to a rare rotary automobile.

Vehicle has a 13B motor with a Holley carb.

Please let me hear what you guys have to offer. Thanks all.

-Ray

 

Rotarys seal fuel mix in the combustion chamber similiar to piston engines. They use 1 metal side seal, the o-ring carrier and the o-ring. If you're getting fuel vapors in the crankcase, it's bypassing the seals as it does in a piston engine.

Since you're running the Holley, you may be running it to rich.

 

So basically said it is the equivlence of bas piston rings. That's no good. Funny because it did it months ago when I first bought it and it seemingly stopped. Then today it happened again in the high RPM snap throttle. Maybe being so cold it was the effect of "seeing your breath." Doubt it though. I'd like to hear more about this. You ever see this? If someone could post a diagram of this metal side seal, o-ring and carrier assembly I would appreciate it. How critical is this to the longevity of my motor?

 

If you snapped the throttle shut at high rpms, minorly worn seals will smoke. Some members have found that Lucas Oil Tratment will cut down on the smoke. The extra burning oil can actualy lube the apex seals more, possibly extendeding the engine life. Main cause of the blowby is the o-rings, but carboned up side seals and control rings can contribute to it if they are sticking.

Look in the FSM in the engine section. The rebuild section will show all the parts.

 

Alright then not all that bad. My understanding is that it will not harm or hurt the engine any time soon. I had no idea, because such problems with piston motors usually mean poor engine performance and extensive work being required.
Kind of funny how it can actually HELP the engine. Long live the rotary. Really strange how it does it so randomly months apart. Thanks alot Trich. If you feel anything else should be added, then please, by all means do so.

-Ray

 

I'm not a fan of those breathers. They only belong on piston engines, if that.

To keep the moisture from building up in the "crank case", I run a vacuum line from the nipple on the oil filler neck, to the base of the carb. Others like to get all fancy and add a pcv valve, but I haven't had issues running without one.

Also, if the car has not been driven much lately then the seals may work themselves loose with a little use, and start sealing better. Running some Seafoam through the tank can speed up this process greatly.

If, after all that, you are still having issues with fuel vapors in the crank case then you can either choose to ignore it or try adding Lucas in place of oil. I use 1 quart with every oil change (due to my horribly worn oil control rings) and it works wonders.

Holland Michigan is only a couple hours away from you, and we're starting to have monthly meets. The next one is April 28th, and will take place right after the first Autocross race in our area for the year. If you can make it, you will be more than welcom. Had a couple rotorheads at the last meet a couple of weeks ago that were from Chicago. Good luck!

 

I really appreciate the invite, however with work I don't know if I can make it. I would love to come sometime to one of them though. You say it may be because it hasn't been driven and it has been about a month since last started since I have been out of town. I am sure the seals will settle back in place after a short trip. These rotaries seem to be quite forgiving.