RSandy

iTrader: (1)

right, just wana make sure im not gonna run into any aggro later down the line, cos im struggling to get decent answers out of local MOT places

iv smoothed over my fuel filler cap recess on the outside of my s2, due to the recess being rusty etc. and the plan was always to then mount it on the inner wing directly behind, retaining the standard tank, and 90% of the original pipework

iv got a cap and funnel, and some 2" bore flexi fuel neck hose, to join the cap to my standard cut down piping, obviously clamping it securely, and also gonna run some PU sealant round to seal it up safe. im thinking this in itself wont be a problem?

next up, the breather/return pipe that usually rejoins the main feed pipe for refueling to let the air out the tank, this iv cut and is at the same height as the cap, but instead of rejoining the pipework and breathing back into the cap and the cabin, iv got it open to air, and will just put a little gauze over to stop crap getting in. again, is this sufficient? this is the bit thats worrying me to be honest

im doing the job safely, using as much original pipe as poss, and then only using proper flexi fuel hose as a joiner, and it will all be clamped/sealed securely. just dont want some picky MOT man saying its wrong for it to breath to atmosphere and not back into the piping, or that there shudnt be joins in the filler neck pipe

any advice would be great

Matt Baxter

iTrader: (37)

As long as there no leaks andthe cap has a proper seal then there wont be a problem as far as the mot goes, but tbh I would put the new filler behind the rear number plate and put the plate on with Velcro or the like

RSandy

iTrader: (1)

was gonna use a hinged metal rear plate, using a set up like on my mates 65 impala, but relocating behind the plate has been done to death by corsas n shit, iv only done it to get rid of rust and look a bit cleaner lol. plus with it behind the plate, i have to mock up a lot more pipework, as there isnt a straight run to the standard tank from there

Carlos-Titx

Putting the return pipe to atmosphere? Would of thought you would be losing fuel through it evaporating which petrol does at a very fast rate. The fumes displace air so eventually the fumes will fill and then get out and keep going as it is not sealed?????

RSandy

iTrader: (1)

the fumes through that pipe would normally go back into the pipe, and escape thru the breather in the cap, but in this case if they escape thru the cap that will be into the cabin, so surely my breather needs to go to atmosphere? if i seal it completely, i wont be able to fill it up with fuel without it constantly back filling whilst displacing air

Carlos-Titx

I didn't think the tanks vented to atmos through the filler cap. I thought it was sealed and the breather pipe was there for filling up. So you would get fumes when filling any way so having the return would help fill but with the fuel cap on its totally sealed?

I would of thought any form of vent to atmos with regards to fuel would be a fail due to how flammable fuel vapor/air mix is.

I'm not really helping here as I don't know, just thoughts on it. Sorry mate.

RSandy

iTrader: (1)

its ok mate, its a confusing situation i will admit lol

the tank itself has a small breather on top which is piped to breathe to atmosphere. then this extra pipe is there purely to let the air return back to the top of the filler neck so it fills smoothly. then usually it rejoins just before the cap, and then the cap has a small breather pipe off it, also to breathe to atmosphere

my new alloy cap doesnt have a breather pipe off of it, so if i rejoin that filler neck breather, the only place it will breathe is through the cap itself i suppose, which will just make the car stink

but i do see what youre saying, having a fair sized pipe open at the end could let fuel evaporate. i dunno wot to do now at all lol