69 911 "crankcase breather longer pipe ?" can't locate external diagram

[H.G.P.]

Looking at my Haynes Manual, I can't find a complete external picture of the oil breather outlet housing with the longer pipe directly behind it (best I can describe it). Is the longer pipe (whatever it is) to be blocked off?




69 911 "Little Bull"

[H.G.P.]

...and there are two electrical connections attached to this "housing".

[H.G.P.]

...and the longer narrow pipe is facing to the left when viewing from the rear of the car.

[Jim Sims]

The longer, smaller diameter pipe that goes to the left or the driver's side is the nozzle to receive the return oil line from an MFI fuel injection pump. The shorter but larger in diameter pipe to the right or passenger's side is for the breather hose to the oil tank. I presume you no longer have an MFI system if you're asking this question. If this is the case you can simply plug the smaller diameter pipe. There are some good photo's of this system as it was originally configured for a MFI system on pages 148 and 149 of Lindsay Porter and Peter Morgan's Haynes Porsche 911 Restoration Manual. Cheers, Jim

[H.G.P.]

Thanks Jim. (Yes, converted carbs)

[joehahn]

Does anyone have an digital pic or parts diagram they could post to clarify?

I know which is the oil breather hose (big) but I have a small diameter hose off the back of the air cleaner housing that leads to a small tube in front of engine bay that conveniently drips onto the floor of wherever I park. I am not sure why oil makes it all the way up into the cleaner housing, nor do I understand why it evacuates into a tube that simply opens to the bottom of the car. In the interest of parking spots all over the area and the environment I would like to fix it.

Joe 68 L

[Jim Sims]

Joe, That tube off the bottom of the air cleaner housing leads to a small rubber "duck bill" type drain valve mounted on the engine sheet metal on the front passenger side just below the engine sheet metal to body rubber seal. The valve is near where the wiring harness passes through the sheet metal on the way to the starter. This valve is to drain unwanted liquids (usually oil) from the bottom of the air cleaner housing. I recall reading in an old "Up Fixing" volume that there are instances where oil in the tank (at nominal fill levels) expands due to entrained water vapor and combustion products (oil tank "mayonaise") and pushes oil through the breather hose into the air cleaner housing and then out onto the ground through the duck bill valve. This was the result of not having a good hot run to clean stuff out of the oil? Your oil level could also just be too high. Cheers, Jim

[joehahn]

Thanks Jim! and you are right, there is a rubber "finger" type thing off that tube that leaks the oil. My dipstick reads dead center so I am not sure I have too much oil in there? Any ideas on what to do in the alternative? Hot run = long drive in hot weather? Thanks.

Joe 68 L

[Jim Sims]

Run time: 30 minutes with the oil above the boiling point of water at your altitude. For Ohio, I'd get the oil up to 215 degrees F. I may also have the scenario for oil getting into the air cleaner incorrect; I'll have to go reread the article tonight. Jim