Spitfire Petrol Tank Venting

[Paul L]

I will be using my donor Spitfire 1500's petrol tank in my Cordite build.
There was some perished rubber remains on the top of the short open pipe you can see here...
( Excuse the poor photo )



Neither Rimmer Bros, nor Canley Classics, stock a replacement 'vent cap' part.
A bit of internet searching suggested this part is used to seal/cap the pipe, not vent it.

The internet debates covered two main areas:
- The petrol tank will be sufficiently vented through the petrol cap.
- The petrol tank venting pipe was really a requirement for the US market.

This is the filler cap I will be using on my Cordite (again from my donor).
But I couldn't see any difference in the Rimmer Bros. photos of vented & unvented caps.
(i.e. No obvious pin hole in the top of the cap that I've seen on some motorbikes.)



But the inside rubber seal if definitely the vented one...



So my questions for today are:

- How can you tell if the filler cap is vented?

- If it is vented, I can safely seal this open pipe in the petrol tank can't I?

Cheers, Paul.

[Psycho pops]

Hi I went through the same issue, vent or not. I don't believe my cap is vented and so put a short length of fuel pipe on the stub and a disposable plastic fuel filter on the end just to remove the risk of anything getting in.
I have sealed off that side of the tank from the car compartment so shouldnt get any undue smell in the cockpit, just so long as my petrol doesnt all evaporate on a hot day I hope these steps will be adequate.
Unless of course someone out there knows different.
Pops

[davecymru]

I had a short length of rubber pipe on that vent when i got my tank, i simply replaced that with a 'new' short length of rubber fuel pipe and that's seen me good for this last year/1,000 miles, so that'll do me!

[Paul L]

Thanks chaps.

So is it simply the rubber seal that makes the filler cap vented, or is there something else I should look for?

Cheers, Paul.

[MoriniMan]

The very simplest tank vent is a length of tubing with several coils in it and the end level with the bottom of the tank. This will trap any fuel that splashes into the vent and fuel won't pour out of the vent if the vehicle is rolled. It might of course pour out of the cap if the seal isn't good!