rusty's_silver_bullet-7

I have a freshly rebuilt motor (Single Turbo set up) and have been getting gas in my crankcase oil. I have a catch-can set up on the upper crankcase vent and I'm getting almost pure gas in this as well (small amounts). Just changed my oil yesterday after 1000 miles and the oil looked and smelled like it was full of gas.

I've done a couple of searches on the forum but haven't found anything directly addressing this issue. I'm thinking leaky injector (o-ring) and I'm planning a "leak-down" test after running the fuel pump to test for this....

Anyone else seen this annoying problem? Any ideas?

Car starts (and is running) ok. Mods in sig.

XSTransAm

gas in the oil is a common problem, i havent been able to find out where mine is coming from, maybe the combustion chamber blowby?

spurvo

If I recall, didn't Goodfella find that tighter tolerances on his side seals solved this probelm, as it is blowby under turbo pressure that causes it? I have it too, BTW, have since I got the motor from Pineapple...

KaiFD3S

iTrader: (37)

Have that same issue to...but car runs fine with it so I'm not to worried about it....

Mahjik

iTrader: (1)

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/gas-oil-filler-neck-312496/

CowsniperRX7

iTrader: (3)

I too have this problem. It just makes me want to change my oil more often which is a good thing.

rusty's_silver_bullet-7

Appreciate the feedback from everyone but I think we're talking about some different issues here. I have had my car for over 6 years and I know it very well. This is not the "usual" "oil smells like gas issue" that I have had on previous engines (number 4 just went in) - which is inherent in rotary engines. This is not typical blow-by around the side seals.

Yesterday the oil poured out of the bottom of my car like gas - I had asked the shop to collect a sample - which they did. It appeared very diluted with gas - more than the 10% quoted in one of the threads as "typical" after the chemical analysis......

Couple of questions though.....

Is this typical "blow-by" only an indication of the compression around the side and corner seals? Or could the A/F or richness of the mixture also contribute?

GoodfellaFD3S

iTrader: (213)

Good memory . In my case it was *excessively* loose side seals, not within spec at all. Rusty, I was having many of the same problems that you are. I started building my own motors and the problem mysteriously went away. Not saying that bad side seal clearancing is the cause in your case, but it could be.