Have been getting a bit of pressure in my fuel tank for a little while now, have checked the little hole to see if it was blocked by the rubber gasket, it wasn't. Went for a ride in the Peaks on Saturday, was quite warm but not hot, went to fill up with petrol after about 150 miles, really struggled to get the cap open (electric keyless), when I did there was a massive jet of pressurised hot petrol fumes, not very pleasant, filled up and carried on. When I got back home I opened the cap, and again pressure, but no vapour jet this time. Googled it, and it seems in hotter countries it's a bit of an issue, if the tank is over filled, has to be a certain distance from top, then the EVAP canister nonsense fills up with petrol and won't vent. What a stupid idea that you have to try and be precise when filling up, if it did more mpg I wouldn't have to brim it. There seems to very various options to overcome it, I've gone for the easy option and left everything in place, canister, valve, pipes etc, but have modified and re-routed the breather pipe so it can breath easily, rather than going into the stupid canister. Hopefully cured it, will find out at the weekend
you may start getting lamda stuck lean errors if you leave the pipe off from the tank going to the canister.
it does seem crazy and thought there would be a "correction" by now as goes back several years. First i remember vented fuel on opening cap, not on this Forum. this also:- https://www.ducatiforum.co.uk/threads/fuel-boiling-issue.69645/
Ok, I'll have to ride it to see what happens. It won't difficult to put it all back as it was if I have to. It's a stupid idea !!
That sounds great having fuel boiling between your legs. It could coincide with me fitting the keyless cap, don't see why though, See what happens, if errors or still pressure then will try putting the original cap back on.
yes and no. i get why they do it, but it could be done better. i've started seeing quite a few EVAP issues over the last couple of years. usually Vauxhall. depending how badly the EVAP valve fails and in what position it can take a few miles to log an error and or run quite badly if fully jammed open. and just last week i have seen a near new mazda with a contaminated EVAP system due to over filling.
Check the gasket as when I changed mine over once it caused the bike to stall and had to release the cap to start again . There is a small hole that you may have not aligned right or over tightened the bolts . Worth a check
I have checked that, and it runs fine, no hesitation at all, even watched the gasket hole at it as I lowered the cap onto the tank, I'm as sure as I can be that it's lined up
I replaced my evap canister twice before I gave up and vented the tank to atmosphere. I did extend the line all the way down so it vents under the belly pan. I also blocked the line that runs from the canister to the purge valve. I've run it this way for over 18,000 miles without issues. No pressure in the tank, no error messages and the engine runs perfect. On very hot days I do get an occasional whiff of fuel if I'm stopped in calm conditions and the tank is near empty. Small price to pay.
That's good to know, thanks. Don't mind the occasional petrol smell, better than having it spray in your face.
Went out this morning for a quick 50 mile blast, obviously wasn't very warm today but when I got back there was no pressure in the tank or a petrol smell, so far so good.
