Board Logo

Fuel Fumes
Sbug 71 - August 9th, 2011 at 08:28 PM

Here's another one for the experienced Dubber,

I'm getting strong petrol fumes from the fuel tank of the super beetle. I suspect it could be to do with the fuel tank vent system. Has anybody had similar experience or could shed some light on the subject? Open to all suggestions.

Regards.


Bizarre - August 9th, 2011 at 08:35 PM

yep - it will be your vent system

Are all your hoses there??
Does the tank "hissss" when you take the cap off??
Are the hoses cracked??

have a look here
http://www.superbeetlesonly.com/forum/index.php?showtopic=11143&hl=fuel 

and here

http://www.superbeetlesonly.com/forum/index.php?showtopic=11885&hl=smell 


waveman1500 - August 9th, 2011 at 09:07 PM

My advice is the following:
First, replace the seal around your fuel cap.
Second, replace ALL of the breather hoses. Don't bother checking them for cracks, replace everything.
Third, after you have done all of this it will probably still smell of fuel. Buy 98 octane fuel, it smells better. I have a slight preference for V-Power over Ultimate but they both smell better than 95! :D


SebastienPeek - August 9th, 2011 at 09:11 PM

Premium in anything, V-Power is the best!

I have read somewhere that anything above 1966, the valve seats and heads were able to utilise unleaded petrol without massive corrosion. Read it somewhere...
But regardless, I will forever use 98 octane in Zelda and whatever aircooled VW I will own from hereon in.

:)


Sbug 71 - August 10th, 2011 at 05:41 PM

I've always used Ultimate but that is about to change because I'm sick of waiting for a pump while the person in front pays for his fuel and orders a latte and foot long sub instead of moving his car to a parking bay.

I'll go ahead and replace hoses first and see how that goes.

Thanks yet again for the help.

Cheers.


68AutoBug - August 10th, 2011 at 06:54 PM

Quote:
Originally posted by waveman1500
My advice is the following:
First, replace the seal around your fuel cap.
Second, replace ALL of the breather hoses. Don't bother checking them for cracks, replace everything.
Third, after you have done all of this it will probably still smell of fuel. Buy 98 octane fuel, it smells better. I have a slight preference for V-Power over Ultimate but they both smell better than 95! :D


Yes
I use v-power usually or 98...
and I agree about the fuel hoses and breather hoses..
as You can't find the small cracks in the cotton covered hoses

once all those are replaced...

the fuel smell should disappear...

Lee


waveman1500 - August 10th, 2011 at 07:42 PM

Sbug71, just out of interest, does your car still have the condensing chamber thing under the dash? Mine is missing. Could you please take some photos of what your fuel breather system looks like and how it's plumbed? Thanks.


Bizarre - August 10th, 2011 at 09:03 PM

Quote:
Originally posted by waveman1500
the condensing chamber thing under the dash? ks.


Do you mean the one that is in front of the air box on L bugs??

They were a 1975 thing only??

You can see it in one of the SBO links I posted


Sbug 71 - August 15th, 2011 at 08:19 PM

Sorry Waveman 1500. I tried to get some decent photos but couldn't attach them. They weren't good photos anyway.

Basically there's 2 small hoses on the left and right sides of the tank. Each of these hoses goes to a white plastic tube (chamber) tucked way up behind the dash. When you overfill the tank the excess fuel is stored in the plastic chamber. When the fuel level drops it runs back into the tank. I've also read about a charcoal canister mounted towards the back of the car for the vapours to be stored and then fed to the carby but I haven't seen it on my car. Perhaps it was recently removed when the motor was rebuilt and the twin carbys fitted. I'd have to ask the engine builder.

Hope this helps. I'll keep trying with the photos to give you a better picture.


Bizarre - August 15th, 2011 at 08:28 PM

If you are talking about this thing then you need to follow the steps in the SBO link I have posted


SebastienPeek - August 15th, 2011 at 08:29 PM

Bizarre, isn't that an L bug's front?

Cos that looks exactly like mine... Not an S Bugs...?


Bizarre - August 15th, 2011 at 08:31 PM

Correct - but I am talking about the "tube/condenser/chamber" thingie

They crack and stink of petrol


SebastienPeek - August 15th, 2011 at 08:38 PM

Ohhh, my apologies :)


Sbug 71 - August 16th, 2011 at 08:16 PM

It looks a bit different to that one and is hidden up behind the air box but I reckon it's the same sort of set up. I don't really want to replace it cos access is difficult but if it gets rid of the smell then I'll have to. Are these spares readily available from most VW parts suppliers?


1303Steve - August 16th, 2011 at 08:55 PM

Hi

The filler tube can also act like a wick and stay constantly wet but not drip.

You could also have a leaking fuel tank.

Stev


Sbug 71 - September 11th, 2011 at 11:28 AM

It was the 40 year old piece of 50mm hose that joins the filler tube to the tank. I replaced it with some hard core, high pressure oil hose from Clark Rubber. That was the only suitable thing I could find. No auto store in my area had anything suitable.


Bizarre - September 11th, 2011 at 02:40 PM

That "may" do for a while, but keep an eye out for propper stuff

Some one may be able to answer

I replaced mine and it was a lot dearer than I thought
Think I got mine from Earls @ Silverwater