Fuel tank breather

[chris.richard]

I have a roll-over valve on my tank breather outlet, at what level should the hose end go? Above the tank by the louvre or can it go low so fumes go into the wheel well? Does it matter, or would the valve prevent syphoning? :confused:

TIA

[Arthur]

Chris,

It's supposed to go low so any overflow/vent is low to the ground.
I noted that Dave Carson (In Hugh's shop years ago) laid his flat against the frame tube, about level.

I have recently moved mine so its pointing up nearer the louvres. Reason - when oriented down the way, the overflow tube filled with petrol, and it pooled under the car during filling. (actually when started just after filling when the pressure valve return started and with it the vapour pressure) Once it started flowing there was somewhat of a syphon effect, and it could dump a significant amount. Finally got fed up of either spilling it or short-filling an already v.small tank, so moved it to point up the way.
No significant change in tank breathing performance, and no spills.

Arthur.

[David May]

Mine too siphoned out when taken straight down (despite the valve). I've now taken it up high before returning down to vent below chassis level. OK.

Dave May

[Sando]

On the Genuine cars the breather in the middle above the rear window is a Beta tank breather so I'm told. Anyone have one or know if you can still get them?
Tryphon?
cheers
rob :cool:
(plastic screw with a small hole in at the moment till I get one !) :)

[tryphon]

I don't know from which FIAT bin the part comes from but it's indeed mounted in the middle of the rear windshield just below the engine louvres. It vents to the atmosphere.
It is connected, of course, to both fuel tanks and the connection to the tanks is just below the fuel caps.

Factory, and most other, Group 4 cars used a different system that didn't vent to the atmosphere.