94 940 with a B230FT, PCV issue?

mojomello · Post by **mojomello** » 13 Dec 2011, 19:40

Hey guys, I have a 94 940 with a B230FT that "burps" oil out of the filler cap. It usually does this in heavy stop and go traffic, or when driving through parking lots. It also smokes like crazy if it sits at an idle for an extended period of time. I have replaced the vent box and the flame trap as well as cleaned the vacuum line going from the flame trap to the intake manifold. The only "weak link" is the breather hose coming from the vent box to the air intake, which is cracked underneath the foam sleeve and doesn't seal quite right at the point where it contacts the air intake. Am I on the right track? I hope it's as simple as replacing the breather hose, but I wanna make sure.

Post by **billofdurham** » 14 Dec 2011, 12:17

I have replaced the vent box and the flame trap

The turbo doesn't have a flame trap so if you have put one in it may be restricting the flow.

Bill.

mojomello · Post by **mojomello** » 14 Dec 2011, 15:36

Isn't the flame trap the little plastic elbow that attaches to the top of the oil separator to which you connect the breather tube and the vacuum line?

Post by **billofdurham** » 15 Dec 2011, 11:44

The attached shows the difference between the crankcase ventilation system on the 940 turbo and the 940 non-turbo engines. It is part #5 on the second picture which is only used on the non-turbo.

I would suggest replacing the breather hose as it is obviously broken but don't think that will be the cause of the problem. Oil coming out of the filler cap is usually because the filler cap seal needs replacing.

The breather box, if clogged, can cause the turbo to blow oil through its seals. Since you replaced the breather box has the smoke diminished at all?

Check the hoses and fittings to and around the turbo to be sure none are loose or have leaks. This can cause poor acceleration or running rich. If the turbo has lots of miles on it you may have a bad turbo which is blowing oil. Don't drive with the turbo blowing oil as it will clog the catalytic converter.

Bill.

mojomello · Post by **mojomello** » 15 Dec 2011, 16:24

Thanks Bill, I'll get on that this weekend. Sorry about the mix up with the part terminology, IPD has both that elbow and the attaching hose that connects it to the oil separator listed as "flame trap hose and flametrap"

mojomello · Post by **mojomello** » 15 Dec 2011, 16:32

The filler cap is new, I even change out the seal because it was still doing it even after I replaced it. I have to bend the tabs after every time I take it off, or things get messy. So, no that situation hasn't improved at all. I did happen to notice that the coolant level was slightly low, and I added some. Wouldn't you know it, it stopped both problems. This, I don't understand.

Post by **billofdurham** » 16 Dec 2011, 11:33

Coincidence? The turbo does need coolant and possibly with that being low it wasn't cooling enough.

Bill.

mojomello · Post by **mojomello** » 17 Dec 2011, 07:38

Ok, it still smokes. I got stuck at a train crossing, and I looked in my mirror and saw a huge cloud behind me. I think you're right about it being turbo related, if I hold the brake and gas it till my gauge registers it'll blow all the smoke out and stop for a minute, but if I just rev it while in neutral, it doesn't effect it.