1972 oil vent hose questions

[rickO]

I'm not new to the forum but this is my first post. I’m also fairly new to early 911s.* Currently trying to sort out the various vent hoses for a 1972T--the oddball.* The PET diagram isn't much help.

The picture should help.


1.* I have a new, preformed hose that (supposedly) runs from the crankcase breather to the Oil tank.* I'd like to confirm that this is correct and that the hose connects to the rearward, upper vent outlet on the oil tank (It also seems to fit OK on the forward, lower outlet) See 2a as related. *Also, I'm unsure which way the hose is oriented as it seems to fit either way.* The best way seems to be with short bend on the oil tank end, which sends the hose back behind the air cleaner and air cleaner vent hose.* Part number on this hose is 930 107 399 00.* The hose previously one the car is a length of plain braided line, which seemed to work fine.* Both ends have hose clamps.

2.The air cleaner has three vent lines:
a.* Supplier provided a braided 24mm line for the run from the air cleaner T to the oil tank.*(Part# 999 180 035 5A) Fits fine, but want to verify that this line runs from the air cleaner to the forward, lower outlet on the oil tank.* Also that there are no hose clamps. (Picture shows nut driver stuck in this line simulating the t-connection)
b. *7.5 mm line runs from air cleaner drain to drain valve on front of engine.* No question here. *(Part # NLA 180 030 52)
c. *12 mm braided hose connects to air cleaner T (opposite the 24 mm flame trap outlet) (Picture shows nut driver stuck in this line simulating the t-connection) and runs across and down the drivers side of the engine compartment and connects to a hard line between the frame and transmission mount.* Where does this hose eventually end in the front of the car? (Part # NLA 180 029 50)
d.* In messing about with the above line (C), I discovered another (12mm?) line that is not connected to anything.* This hose was laying along the firewall hiding behind the wiring harness.* The end is about 6" short of the passenger side shock upper mount and has a hose clamp.* This hose parallels the Air cleaner hose (in Question C) and goes across and down the drivers side of the engine compartment and connects to a second hard line just inboard of hose in Question C.* Marked with a piece of yellow tap. I have no idea what this line is or where it goes so any help would help.
e. Is removing the transmission crossmember to gain better access to replace these two lines advisable? I can see the clamps but there isn’t much room to work. *

Thanks so much.* Just trying to sort it and get it right.* RickO

[Rusty]

Come by for lunch, maybe we can figure it out.

[Richy]

The other 12 mm braided hose goes to a fitting on the fiberglass engine shroud . It runs between the mfi pump and the mfi lines . It is part of the charcoal fuel evaporation filter system . You may need a longer piece .

[EsGeht]

Parts Book shows upper vent hose (#36 in illustration) attaches to air cleaner at spark arrestor, passenger side, lower vent hose attaches to engine (#33). In picture of my '72, upper large braided hose (#36) attaches to air cleaner at spark arrestor, passenger side; lower large braided hose (#33) attaches to engine, at breather. Smaller braided hose (the one lying along the firewall in your picture) attaches to the spark arrestor, drivers side. Smallest rubber hose attaches to air cleaner drain and leads to front of engine, drain outlet.

[rickO]

Thanks so much for the info and the pics. Helps greatly--I should be good to go now.