Gidday,
Petrol fumesin the cabin and boot, how does one eliminate this annoying problem ?
Les.
Gidday,
Petrol fumesin the cabin and boot, how does one eliminate this annoying problem ?
Les.
Apart from the obvious of checking for leaks, the fuel tank breather hoses may have perished. Check where they exit under the rear wheel arches - if one of them is no longer poking out of the grommet, itâll be venting into the car. Apart from those two pipes, thereâs a gasket around the fuel sender unit thatâll make a pong inside the car.
Good luck.
Sean.
Greetings, possible solutions have been described on a lot of previous threads here.
I suggest keywords âfuel smell +2 ventsâ or something like that. There are several things on a +2 that can create your problem. Tank venting seems to be the culprit frequently and the remedies vary.
Hi
I have an early +2 and the vent pipes just poke through the wheelarch and hang there, so I do get a lot of smells.
I have just replaced the cap seal and this really cut down the smells. I got the seal after much searching from SJ sportscars I think it was about ?2.
give them a call.
Jason
The vent pipes are the worst cuprit, but I recently discovered that there are actually 2 seals on the fuel cap. One is the big âwasherâ that seals the top of the filler pipe. The other is a small rubber âtubeâ that sits behind the other one & itâs sprung plate, in the middle of the cap inside the spring. This one seals the sprung plate to the cap. Take the cap apart & youâll see what I mean. If either one isnât working, youâll not only get a smell (outside) but the common overflow of fuel down the rear wing around righthand bendsâŚ
Matthew
Interesting, Thanks.
Les.
Hi All,
I am looking to replace my petrol tank vent pipes. The original ones have lost all of there flexibility and would probably crack if I attempted to change there shape.
Can anyone suggest a supplier for this pipe or confirm the diameter?
Thanks
Dave
Paul Matty lists Breather hose at ?1.75 (per metre presumably)âŚ
I was thinking of getting them to replace mine as I donât fancy trying to remove the rear screen - any ideas how much theyâd charge?
Dave,
Spyder (Andy) told me that the pipes start off flexible but harden rapidly (possibly due to the effects of petrol fumes?). They are then difficult to remove. He sees this as standard and it helps the pipes hold their position over the back of the screen. It may be a red herring but you may not need to change the hoses.
The Spyder solution takes the output from the vents to a âTâ piece in the fuel filler. This is fine for putting any excess fuel and fumes back into the tank but doesnât vent for any pressure variations. The fuel cap has to leak to accommodate pressure changes.
For my rebuild, Iâm planning to put in standard pipes to the top point where they will join at âTâ piece with a small diameter vent pipe leading to one wheel arch. That should allow the system to breathe while limiting the fumes. Not my idea but it seems a good solution.
Iâm very open to other ideas.
Mike
A standard +2 petrol tank requires large diameter breathers to enable filling of the tank beyond half capacity. This is because the filler pipe feeds into the tank half way down. If you only have small bore breathing capacity it will enable the tank to breath for normal running, (if you have a breathing filler cap) but will take ages to fill the tank beyound half full. Piping the breather into the filler kneck will not enable the tank to breath under normal running. The standard filler cap is fully sealed and 2 psi suction on a petrol tank is enough to collapse the tank.
Standard 1/2" bore polyhene pipe is all you need from any plastics suppliers. Make sure the two pipes run over the roof lining and exit out the inner sills through new close fitting well sealed grommits otherwise the fumes will get back into the car. This requires removal of the rear screen and carefully peeling back the roof lining.
Gordon
Thanks to all. The replies were, as always, very helpful. I was also wondering if anyone had looked into the modification shown within the owner?s manual where they fit carbon canister filters?
Has anyone ever done this or come across a car that had it fitted? Are they still available and did it work?
I know ultimately there would be a usable life for the filter as at some point the carbon would become saturated. I have looked on the web but have been unable to find a suitable supplier - anyone else looked into this?
Any thoughts
David
Dave,
Iâll look at the manual tomorrow, I donât remember anything about carbon filters. However I am dubious about whether they would deal with the volume of fuel involved.
My reply to Gordon also seems to have gone astray (with my memory?) Gordon is absolutely right with his comments but unfortunately, the result of the standard half inch hoses is a a garage that stinks of petrol and I am still after a solution and I know a lot of other owners are too.
We need a way of venting the tank to allow filling while preventing fuel/vapuor escaping in large quanitites. Has anyone got a solution?
Mike
The charcoal canisters are part of a vapor recovery system as now mandated and in all cars. The tank vents through the canister which absorbs the fuel vapor and when it is saturated it returns the vapor to the carb to be burned.
I had a new alloy tank made by Axminster Specialist panels. As I specified, the tank height was lowerd to make room for two Mocal breather vents. The vents are supposed to close to the atmosphere between a pre-set negative and positive pressure. What that is I do not know. In addition they will prevent fuel from exiting in the event of a turn over, full tank or âsloshingâ fuel in turns.
I have attached a photo of the installed tank. I have a few gallons in the tank and have run the engine. The car is in a large shop and there is no smell of gasoline. Either the vents work or the volume of air in the shop disperse any fumes.
Bob
Bob,
Looks like you have a neat solution, can you give a few details please?
Do the Mocal valves vent into the boot or do you have a pipe leading out somewhere?
Does the tank still fill reasonably quickly?
Did you think about putting the valve on the standard outlet (where the pipe goes vertical). Iâm would rather retain the original tank.
thanks
Mike
Those look like serious earth straps
Matthew
The Mocal breather vents have a rubber fuel line attached. I attached an AN -6 90 deg. elbow barbed to the vent and pushed on the vent hose. I route it directly to the wheel arch exits. Crossed above the tank rather than above the rear screen. I have attached a photo that details the hose hook up. I have since added a hose clamp.
I have a roll of the ground strap. It will work properly but does have an unnecessary âheavy dutyâ look. It will be hidden behind the boot / tank panel.
Bob
nice setup M8
Bob,
looks excellent.
Iâm sure that the pressure settings on the Mocal valves will ensure that they are normally shut and prevent petrol vapour escaping in normal use. After Gordonâs post, I guess my only concern is whether the back pressure slows the tank filling. Have you tried it yet?
By the way, I looked up the carbon filters on the 'net. We donât have the rule in the UK so it was news to me. Looks like the US is very keen on reducing emissions from fuel eveporation through fuel tank breathers, must be your hotter weather. Driving gas guzzlers and then worrying about such small issues, have I missed the point?
Mike
I assumed that evaporative emissions were responsible for a large part of air pollution and relatively easy to control. With hysteria the norm and environmental crazies everywhere it is difficult to tell where the truth lies.
I have not filled my tank but I cannot see why the breather vents would alter filling ability.
I will soon have the car âon the roadâ (at least 3 blocks from the resto shop to the upholstery shop). I will let you know.
Bob
If you squeeze the filler pump handle too hard once you are passed half full the petrol will fly out and soak you. Take the polish off the car body as well not counting the fire hazard. It does this anyway with good full bore breathers and can only be worse with restricted breathers. Can take ages to fill tank to the brim. Takes the edge off having a quick release filler cap donât you think?
In passing, how much petrol should a +2 tank hold, the manual says 10 gallon (Imperial) a few more American. I have only managed 9 and a bit in mine.
Gordon