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Petrol tank venting

5 May 2010, 7:53am
Hi
I've got a Carisma Century SS100 replica running on cortina/sierra mechanicals. I have had great trouble putting petrol in without it blowing back over the paintwork. I even tried using a filler can and a funnel. There is a vent at the top of the tank and I discovered last night that a previous owner had blanked this off with a bolt - idiot! I haven't tried refilling since this discovery but I'm sure it should make a significant difference.
The question is - what should I do with the rubber hose now? (no medical jokes please) Some valves seem really expensive.
I also want to relocate the filler but the flexible hose I need costs £18 + VAT + carriage for 0.5 metre and I need almost 1 metre. It's 60mm or 2" id and needs to be flexible. Anyone got any ideas - I've tried Car Builder Solutions. Additionally I need an adaptor which costs about £16 so it could turn into a costly exercise - minimum £60 plus the cost of a valve.
All advice gratefully received
Ocheye
5 May 2010, 2:58pm
Route the vent pipe up as high as it will go (above the filler) then loop it over and back down as low as you can go without it protruding from the bottom of the car and make sure it is away from anything hot (exhaust).

It is important to make sure it is above the filler so the fuel level will not reach the top, otherwise you will create a syphon and get wet and rather flamable feet! You then take it down as far as possible, so the syphon effect won't happen if god forbid you roll the thing
5 May 2010, 3:05pm
Petrol tank venting

Hi Chris
Thanks for the very sensible (and cheap) solution.
The only problem is that the filler cap (Aston type) is mounted on top so I can't get up that high with the vent pipe. I can get within an inch though and the nozzle will be below that. I am unlikely ever to fill it to the brim though. Do you reckon I should be OK?

Andy
5 May 2010, 3:08pm
That would have to be you're judgement, just think how far you have to stick the nozzle in
5 May 2010, 3:26pm
chrislandy wrote:
That would have to be you're judgement, just think how far you have to stick the nozzle in


Should be OK by my reckoning and I would have to overfill the tank which is unlikely on my budget! Any thoughts on flexible filler pipe?
CARISMA (Derek Back 2).jpg

This attachment isn't my car but shows the position of the filler cap.
5 May 2010, 3:34pm
When I made mine I used straight petrol hose (preformed bends are expensive!) and pre-bent 2.5" mild steel exhaust pipe sections
5 May 2010, 4:21pm
Hello Andy

Just a little word of caution...

Petrol hose is expensive because its composition is diffferent to your ordinary run of the mill rubber hose. If you find a cheaper alternative - make sure that it is rated to carry petrol - otherwise you may suddenly find it has become permeable!

Robin
5 May 2010, 5:15pm
Ah yes, I should have said, I used roughly 3/8th bore thin wall aluminium tube for the vent pipe which I connected to the tank using petrol hose.