+2 Fuel tank breather

[h20hamelan]

It would be interesting to find out more from rdssdi, though maybe time is not on our side.

https://www.carbuilder.com/uk/fuel-tank-breather-valve

Same as the Newton, Pegasus is 4x as much $

https://www.pegasusautoracing.com/produ ... RecID=8453

I wonder if making the filler threadable

0A773C6A-7FCC-4B20-9577-0B6F8561C889.jpeg (67.99 KiB) Viewed 986 times

[mbell]

Many cars use carbon vent canisters ?

Modern cars have "EVAP" systems to avoid fuel fumes escaping to the atmosphere. These are carbon canistor that are used to capture the fumes and some plumbing/solenoids that allow the fumes to be sucked into the intake and burned at a suitable time.

These systems also have monitoring capability to ensure the tanks are aren't leaking fumes and the systems are working. These are the most common cause of check engine lights on modern cars.

Now, if I could find a way of converting these old cars to capless tanks, I'd be happy..

I think that would be quite ugly unless you relocated the filler into the trunk or something. Lots of options for different setups at:
https://www.fillernecksupply.com/

[h20hamelan]

Modifying this somehow?

[lomh 13]

Today I received my two filters and I filled them with activated carbon that I use on my boat.

I installed them at the outlet of the two vents for testing.
Head to the gas station to refuel. I no longer smell gasoline in the garage.
No modification of the original circuit, 5 € for the two filters and 10 minutes for the installation.

[JJ66]

Hi All, Its taken me some time but I have finally rebuilt my fuel system: POR15 treatment of the tank, rebuilt fuel pump (original mechanical AC item), cleaned out carbs and revised breather system. For the breather system I followed the same practice as many others, brief overview of how I did it as follows:

Welded a 3/8" BSP collar into the filler neck, below pic shows finished job with brass fitting screwed into the collar:

The collar protrudes into the filler neck by about 8mm and is no issue for the pump nozzle. The brass fitting is a 3/8" BSP with 1/2" OD tail, bought from CarBuilder.com. When fitted it looks like this, brass fitting equally spaced between the rubber grommet and the neck clamp:

I made a manifold block out of aluminium and stuck it to the top of the tank with velcro, this manifold block has 3 x 3/8" BSP with 1/2" tails, same as the filler neck, the fourth outlet on the manifold block is 1/8" BSP with a 1/4" tail:

Next Pic is close up of the manifold block and the collar for the filler neck:

I made two of each part and so have one manifold block and threaded collar for the filler neck spare, If anyone would like them (FOC) just DM me and I'll send them.

The 3/8" larger bore fittings are connected with 1/2" ID breather hose from Car Builder, a pipe goes from each of the breather spigots at either side of the tank to the manifold block, then a 1/2" pipe form manifold block to filler neck, this takes care of the need for fast breathing during filling. The small bore pipe then goes from the 1/8" BSP tail and goes up through one of the original breather pipes, up and over the screen and out at the lower cill. Only one is needed as that's all you should need for breathing when running. With plenty of washing up liquid (Fairy, of course) I was able to feed the small bore pipe up through the original, it wasn't easy but I got it on the 5th attempt!! Very pleased to do this without disturbing the headlining.

Below pic shows small bore pipe poking out from original large bore

This all seemed to work quite well and I am super pleased with the result in terms of fuel smell in the garage, basically there isn't any which is a huge improvement!! The car is running fine and fuel filling is good.

Thanks to all for the previous posts with ideas and suggestions on how to do this. Don't forget, please contact me if anyone would like the spare manifold block and threaded collar.

Thanks, Jonathan

[Peter +2]

Jonathan

PM sent.

Peter

[alfadave]

Further to lomh13 and his charcoal filters......

is there a cheap/simple more user friendly solution? A basic push in filter?

I have the original type of "up and over " vent pipes on my 68 Plus 2

I fill up 3/4 full without a problem, just a fuel smell.

I did used to use 2 corks with tell tale ribbons, but a bit inconvenient.

[mbell]

There are valves designed specifically for fuel tanks:
https://www.carbuilder.com/uk/in-line-f ... hose-tails

But these are just a plug in type solution on the +2. The standard breather setup serves three purposes:
1) Allow air in to replace fuel as it is used
2) Allow air to exit at high rate from the top of the tank to enabling filling of the tank above 1/2
3) Prevent fuel escaping from the breather in a roll over situation

All these function are required and so any modification needs to not prevent them. A filter on the ends of the breather hose may help remove the fuel smell but is likely to slow the rate air can leave the tank and possibly impact filling of the tank.