Sorry idiot question fitting for vacuum ? next to dist cover on engine

[BaronYoungman]

I am trying to figure out what the line (small hard plastic) it connects to a fitting next to the distributor cover on the front of the engine.  My other car is in storage and this line is broken and I cannot figure out what it does or where it goes?  It is a 1970 280sl auto USA.
Thanks, Bob

If no one has a idea I can post a pix after work

[kampala]

Baron,

I am not exactly sure of your question -- think you are not asking about the dizzy vacuum -- so you must be asking about the fuel vapor line.    Since your car is a 70/71 USA model, it probably has all the emissions stuff (or had it at one time)  --- this model has a plastic line that runs from the front of the engine down to a fitting by the crank and this plastic line runs all the way back to the fuel expansion tank on the left side of the trunk.  It takes the fumes and sucks them into the crankcase.

[georgem]

No such thing as an idiot question...............

My guess is that its the vacuum advance/retard  tube- runs from the can on the side of the distributor to the intake manifold - either to the top or bottom, depending if your car is vacuum advance or retard. On my car it is clear plastic which joins with a thicker rubber tube (smaller pushed into the larger - no fitting) just before  it joins the manifold

[BaronYoungman]

here are pictures... crankcase vent? looks  like it was capped off?

[hkollan]

Hi,

That is for connecting the fuel vapor return line on later US model 280's.
It runs under the car from the fuel expansion tank  in the trunk along with the Fuel and brake lines.
It is a black plastic line that often gets brittle from engine heat and age, and eventually brakes.

Hans

[JamesL]

That's a good question idiot

[BaronYoungman]

ok, any reason I should not leave it capped?
Bob

[wwheeler]

Not sure I would have any problem leaving it capped. More of concern is somewhere on the other end there could be a hose with fuel vapors coming out. Might want to make sure of it's status.

[ctaylor738]

You can easily re-connect it with a piece of flexible hose that will slip over the fitting and the plastic tube.