Hose Connections to K&N filters for Carbs- post a pic of yours

[bavaria911]

Team -

I need some help. Drove the car yesterday -- after operation went to conduct maintenance (Post PMCS).
Suprised as I lifed the engine lid, an oily substance leaking from the hoses connected to the K&N filters mounted on the weber carbs, also leaked on the red engine cover.
My hosing has a larger diameter hose mounted on the oil tank, on the other end a plastic spliter leads to two smaller diameter hoses connecting each to the filter lids. This system has been this way for 12 years, but never had this issue before.
I have seen some Pelicans mount a canister with a small filter on top that is mounted near the oil tank. Does this help stop the carbs from pulling oil from the tank?
Is there a better system (other than stock - I do have a MFI stock filter housing in the basement). I believe my hosing is incorrect.

Can some pelicans post a picture of their filter system?

Little help please.
Vr,
Bavaria911

[911pcars]

The post-factory oil tank system is usually vented from the hose at the oil filler tube, to a catch can and then to the carbs or atmosphere (carbs preferred). This is because any oil slung from the crankcase has a chance to slow down in the oil tank. The circuit you describe in your car takes crankcase pressure directly and routes them to each carb. I'm surprised you haven't experienced oil in your filter housings before with this setup unless there's a place for oil to collect and drain back into the engine.

That said, your comment:
"This system has been this way for 12 years, but never had this issue before." tells me this system has worked well for you up until recently. That could mean an increase in crankcase pressure due to blowby (combustion gases leaking past the rings) and/or a leaking hose or loose hose connection. A compression test might be in order to confirm the compression numbers are within spec.

As for venting, there have been a series of lengthy threads (with photos) on the subject. Use the search term, "catch can".

Hope this helps,
Sherwood

[bavaria911]

Sherwood,
This is helpful advice. I am having backfires and blowby issues -- and taking my car to the local expert (AT Speed in Maryland).
I'll look up the Catch Can threads on Sunday.
Vr,
Bavaria911

[bavaria911]

Here is a picture of the breather hoses connected to the oil tank and spliting off the the K&N filters.

Does any Pelican see an issue? The car recently had the gas tank cleaned out and 46 Webers rebuilt - but now badly popping and backfiring. Thus the reason I drove the car to another shop to dial in the webers and tune the motor.
Vr,
Bavaria911

[911pcars]

Originally Posted by bavaria911

Here is a picture of the breather hoses connected to the oil tank and spliting off the the K&N filters.

Does any Pelican see an issue? The car recently had the gas tank cleaned out and 46 Webers rebuilt - but now badly popping and backfiring. Thus the reason I drove the car to another shop to dial in the webers and tune the motor.
Vr,
Bavaria911

The breather setup you have is typical. The hose to the K&Ns is from the oil filler tube. I see no issues there.

So, in addition to an oil film in the engine compartment, the carbs are acting out following gas tank cleaning? I'd say not related.

Issue #1: oil leak
Isssue #2: A/F mixture

Let's see what your shop says.

Sherwood

[RoninLB]

Do I see a red engine shroud in that pic?

[bavaria911]

Why yes you do. It's an original red one.

Bavaria911