I've just broken the small line (vacuum?) that runs from the breather hose and disappears under the air filter housing. What is the line for?
Where does it go?
Is it easy to replace?
& What is the line made of?
The plastic is very brittle (@70F) and yellowed. It does not appear to have any oil residue on the inner surface. Other than a general concern about my status as poster child for carelessness, does this deterioration of the tubing indicate anything more troublesome? Thanks.

Yep, pulled off the cover and it basically shattered in three pieces. I've got 4mm Teflon tubing on hand and am wondering if it might be a suitable replacement? It's fantastic stuff, but I don't know specifically what the old stuff is - polyethylene?, so I don't know if it was chosen for some specific reason. Does the female fitting have to be replaced? Thanks.

The small plastic line is a vent from a pressure damper in the fuel circuit. It shouldn't affect the way the car runs. Its there "just in case" the diaphragm in the damper ruptures. I guess they figured if the leaking fuel went into the air cleaner, it was safer than having it spray all over the engine.
Regards,
Randy D.

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W.R.Durrance
ASE Master Tech
Mercedes Tech 20 Years
68 250SE
68 SAAB 96 Ice Racer
69 300SEL 6.3
70 300SEL 3.5
81 300TDT

Chris & Randy,
Thanks very much for your help. I hate it when I break something without knowing what it does. I'm going to give the teflon tubing a shot - it's rated for -400F to +400F, compared to -100 to +175 for most low density polyethylenes. It remains flexible even with liquid N2 running through it, doesn't suffer from age embrittlement, and is chemically inert to just about everything. You can run 300F hydrochloric acid through it continuously with pretty much no effect. Do the other vacuum lines suffer from the same malady?

John