oil breather hose

[Adelaide901]

Has anyone got a picture of where the oil breather hoses should go in an early 911 (1971)?

I seem to have one from the tank to the top of the engine, and another from the oil filler neck to the air box. However I am not so sure if the one to the air box is correct, it leaks a lot of oil from it.

Help please!

[Flat6pac]

Thats the way they go.
The one to the air cleaner forward is used to pull in the oil fumes and burn them the other uses the tank to breath the oil fumes from inside the engine.
becareful of your oil level after warm up. You dont want it running into the carb area
Bruce

[911pcars]

Originally Posted by Flat6pac

Thats the way they go.
The one to the air cleaner forward is used to pull in the oil fumes and burn them the other uses the tank to breath the oil fumes from inside the engine.
becareful of your oil level after warm up. You dont want it running into the carb area
Bruce

Yes. Check oil tank level only with a hot engine. Even then, many folks run with 1/2-1 qt. less than "full" on the dipstick to prevent this.

Sherwood

[Adelaide901]

Thanks for the reply guys.

I have seen the K&N breather hose filter on Pelican, are there any down sides to installing this that you are aware off?

[911pcars]

Originally Posted by Adelaide901

Thanks for the reply guys.

I have seen the K&N breather hose filter on Pelican, are there any down sides to installing this that you are aware off?

Here's a couple:

Unburned hydrocarbons introduced into the atmosphere.

Does not address the collection of oil while venting the crankcase; excess oil may coat the engine compartment in small or larger quantities.

Other than that, no.

Sherwood

[RWebb]

for "may", substitute "will"

and it does not have to be "excess" in the sense of slightly over-filled -- hard driving will put an oil mist on your B-you-T-full carbs or MFI stacks...

[trekkor]

I just got a tip from a well known 911 racer on breather hoses.
He suggests installing an inverted cone, inline in the breather hose with a small hole in the tip.

This allows fumes to go through the center hole, while the oil accumulates around the cone and flows back into the motor through the breather outlet.

I haven't spent any time searching for this 'cone' piece, but I will.


KT

[911pcars]

Originally Posted by trekkor

I just got a tip from a well known 911 racer on breather hoses.
He suggests installing an inverted cone, inline in the breather hose with a small hole in the tip.

This allows fumes to go through the center hole, while the oil accumulates around the cone and flows back into the motor through the breather outlet.

I haven't spent any time searching for this 'cone' piece, but I will.


KT

This sounds like a cone-shaped cap with a hole in it. What makes him think only fumes will exit the orifice? There should first be a mechanism to separate fumes from liquid.

Sherwood

[minoclan]

Read this thread. I think what you are looking for is pictured in Jack Olsen's post.

Engine wants to die upon removal of oil filler cap?

[Adelaide901]

Thanks guys. The information is gold!