Fabio421

Is there any reason that I cannot eliminate the tube going into the top of the pan from the oil fill/catch can? The oil fill/catch can has drain holes into the vee so it should still work fine for adding oil to the engine via the can. I want to reroute the hose that normally goes to the tube coming out of the top of the pan, and instead, route it to my electric oil scavenge pump. I would then make a blanking plate to seal off the hole in the top of the pan. I would also vent the fill/catch can to atmosphere with a filter on the end of a short hose and the Ott pot scrubbers inside the fill/catch can. Is there anything glaringly wrong about this idea? I have blow by that is adding to the already troubled 928 oil control system and the current itteration of the evac system draws oil into places I don't want it. Currently the vacuum for the catch can comes from the airbox before the filter. I plumbed it with 3/4" hose all the way and it works too well. I have oil being drawn all the way to the airbox. It then drips down the intake tube and onto the ground once I shut the car down. . This is a boosted car BTW.

Please discuss.

Dennis Wilson

Devek used to sell a valve that was installed in the rubber hose part of the drain. It was to stop oil being blown from the crankcase to the separator when there was a lot of blowby on old engines. I think the passage was initially designed to put a slight vacuum on the crankcase and provide a faster fill port when adding oil.

Dennis

Leslie 928 S2

85 Euro....6ish pounds boost.

No catch can. No scavenge pump.







No oil loss whatsoever....




It's Carl's oil control system, with additions of Kevin's own invention and design...the two are merged together. Kevin got sick of blowing a quart of oil every time he took the car out.

It may not be pretty, but it works 100%.

PM me if you want further information.

Fabio421

Leslie... PM Sent.

To add a little background:

I have done a leakdown test. I have an issue with cyl. #7. The leaking air is coming through the crankcase so I know it is a ring issue. What I don't know is if it is a stuck ring or a broken ring/ring gland. I have soaked the cyl. in Marvel Mystery oil and my leakdown numbers have been cut in half. I had a 35% bypass on the first test and after numerous MMO treatments I got only 17% bypass when I did a test last night. So things are improving.

The one think I did yesterday was to take the vent hose from the catch can and put it into a latex glove. It blew that thing up like a balloon. I haven't tried it on one of my other cars yet but I don't think that should be happening.

Leslie 928 S2

That doesn't sound right.

Kevin has had a head gasket leak from the cylinder to the head stud, venting into the crank case...which would cause the same symptoms. There would be some pressure, but he thinks that sounds excessive. Might want to also check your head gaskets.

Is the spark plug fouling in that cylinder?

Either way, it sounds like you need to pull your heads to see what's going on in there.

Fabio421

I just did the glove test on another one of my 928's, an 84. It also blew the glove up like a balloon. I guess this is normal. I did notice a difference, on the 84 there were no visible vapors coming out of the catch can but on the car that I am having a problem with it is blowing vapors like crazy.

I just recently changed the plugs so they are not fouled. When I took the old plugs out, that one was more oily than the other. I will post a pic later.

largecar379

Fab-

another area to look at is the air pump.

with my Euro, I have a bad #8 cyl, and the blow by was really bad. removing the air pump cut this blow by quite a bit. (probably a head gasket issue)

as your engine has a blower, this issue is just magnified.

--Russ

Fabio421

Air pump? Hmmm, now where did I put that thing. I know it's around here somewhere. Some people end up with extra bolts when their finished with a project, I end up with air pumps.

Fabio421

What experience do you folks have with the baffle plate that fits below the stock oil can? Devek made one and 928 Motorsports makes one. How well do they work? Any feedback is appreciated.

Thanks

Tampa 928s

Shawn, have you been to a Doctor about this, sounds painful.

"broken ring/ring gland"

Mark primed my wheels today after 8 hours of sanding this week!

Fabio421

I was encouraged to chop off the portion of the oil tube that goes into the oil pan and is covered by oil. It was thought that the crankcase pressure may have been pushing oil up the tube. I did that but it made absolutely no difference in the amount of oil I am seeing at the catch can brether. Here are the before and after pics of the oil tube. BTW, the oil level is above the top of this part of the pan and that is why this didn't work. The reason I went ahead and cut it anyway is two fold. One, I can't see what use this tube serves and no one has been able to tell me. And two, I plan on eventually eliminating this entire tube anyway if cutting it off didn't work.