Expansion tank ?

[Deschodt]

Ok, my stupid question of the month:

While dissasembling my 83 SC's fenders, I found a tank secured behind the driver side headlight bucket. The PET calls it an expansion tank. My stupid Q, is for the expansion of what ?? It was bone dry...



It's connected to 2 small hoses and I cannot trace them. It seems too big for a brake reservoir overflow, though who knows, and the only other fluid could be for gas but it seems too flimsy for that.. Anyone knows for sure ?

It's NOT the washer fluid tank, it's in front of that... Thanks !

[Kroggers]

Fuel.

[ossiblue]

Originally Posted by Kroggers

Fuel.

+1

The top hose comes from the filler neck/vapor recovery box (if so equipped). The bottom hose goes into the luggage area, runs behind the fuel tank and back into the engine compartment where the vapors are burned via the intake.

The container you found probably would not have liquid in it as it's designed to capture any liquid overflow, allow it to evaporate, and send the fumes to the engine instead of the atmosphere.

edit: Almost forgot--the fumes go into the charcoal cannister in the luggage compartment where they are "held" until sucked into the engine.

edit: Actually, I think I got that reversed--the bottom hose is from the filler neck/overflow, and the top hose goes to the luggage area. That makes more sense as fuel vapor rises.

[Deschodt]

Thank you both ! I'll make sure to put it back on then ! Another reason to stick with my fenders then, but that is another story...

[RWebb]

It is probably time to replace all the hoses -- are they hard, cracked anywhere, or brown? Plastic ones should be clear.

several threads on this... search vapor + emission