what's that part- take two

Started by Repco Lad, July 04, 2011, 10:03:16 PM

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Repco Lad

Whilst every-one has their thinking caps on working on Al's question, can some-one tell me what this valve is for?

Pulled the back seat out and found it hiding behind the rear support.

Looks like it should have a hose coming off it

Thanks

RL

njh1964

Hi RL,

That looks very like the one-way or breather valve for a fuel vapour system. If it is, then it should be connected to a plastic vapour tank inside the boot.

Regards,


Nick
Now:
1968 Alfa Romeo GT 1300 Junior - Complete Restoration Project
2002 Alfa Romeo 147 Twin Spark - Track Day Car
Previously:
1974 Alfasud TI - First Car

Repco Lad

Thanks Nick,

Thought it was either fuel or vacuum related. Doesn't have a fuel smell, but better get onto that asap!

Worryingly, when I pulled the seats out there were a few cigarette butts under the seat. There's a new take on 'breakfast of champions'- Winnie blues and V-max?
Who knew I was (literally) buying an old bomb when I bought it!!!

RL

njh1964

Hi RL,

I'm pretty sure that the one-way nature of the valve lets air into the system (ie to prevent a vacuum lock) so that the fuel vapour can be sucked up to the charcoal canister and then into the intake manifold to be burned off.

Mind you, some spare fuel vapours floating around in the back of the car, add a lighted ciggie, and you've got a much cheaper means of getting some extra boost (one time only ;D) than a nitros system.

Cheers,


Nick

Now:
1968 Alfa Romeo GT 1300 Junior - Complete Restoration Project
2002 Alfa Romeo 147 Twin Spark - Track Day Car
Previously:
1974 Alfasud TI - First Car

Al Campbell

Yep, that's the air inlet valve. Lets air in to the tank in the case of a vacuum. It's fitted to a tee in the vapour line from the oil separator on the cam cover to the condensate tank on the top of the fuel tank (if we're looking at a GTV6).

You should be able to blow into that little spigot. If the tubing is all in good nick and the petrol filler cap seals, then it should be hard to blow in. Take the filler cap off and blowing in should be a little easier. There may or may not be a one way valve to the left of the inlet vale, preventing tank vapour going back to the engine. On the GTV6 at least, on the top of the petrol tank there is a small metal tube that takes the rubber tube from the condensate tank, there is a small metal plug that has a tiny hole in it. It's supposed to stop vapour going back up, if it's blocked with goop after 30 years, you won't be able to blow into the inlet valve.

Do you have petrol fume smells in the cabin in hot weather?

AL.

Repco Lad

Thanks for the feedback.

Checked it out- it's connected as it should be. Will relocate back under the parcel shelf

RL

Al Campbell

#6
Your valve is item No. 3 in the attached diagram.

AL.