Breather hose to air filter cannister

[denson]

Hello:

I own a 1970 911 S. My U.S car has the breather hose that hooks up to the extension on the air filter housing (nose) and hooks up to a connection near the oil filter.

Some pictures of the same motor I have seen do not have this hose, but the air filter housing (nose) is there, but just with without the hose connected.

Is this hose needed?, what does it do?, and should I keep it in place.? If you guys recommend removing it, do I cap the connection near the oil filter?

Thanks for the help! .

[classic]

My understanding is that it has a harm up function for starting, if you look at the pluming it takes heat from the right hand heat exchanger through the flapper and delivers it to your induction intake.

Do you need it? depends on your climate i would think. For me in Australia, mine didn't have it fitted. I found that on early mornings i had to play around with the hand throttle to get her running.

I fitted the pipe and it did start on cold morning easier, or maybe that was my imagination?

[orange911]

My oil tank vent hose is on the back of the filter housing. I believe the intention was to burn the vapor in the motor instead venting to atmosphere. I have seen some put an external tank to catch the oil from the mist and mount a filter on top of the tank. I have also seen the tank used with a line to the air cleaner housing to still burn the vapor and still catch the mist. This is best if you don't want oil getting into your air cleaner.