Fuel Smell in 73 911

[Blue Baron]

Whenever I fill the fuel tank, I get a strong fuel smell inside my car. It usually goes away in half an hour or so. I would appreciate your thoughts. It only happens when I fill the tank. Thanks!

[timmy2]

Tank to filler neck rubber may have cracks?

[kent olsen]

Or the overfill hose

[wayner]

Venting tank


tank http://forums.pelicanparts.com/porsche-911-technical-forum/677889-1971-vapor-canister-delete.html

[grizzfan]

There is some "how-to's" in the search engine which was very valuable for me.

I have a '73 with a '75 CIS engine. Close inspection revealed a real horror story. There are two gas-fume accumulators (for lack of a better term. They are properly named in the PET schematics along with part numbers). One is under the dash in the frunk. It's an almost square, black plastic item with two ports for tubing. Both tubes were not hooked up. It's also a bear to properly attach so I left it to dangle; very light and not in the way of anything important.

There is another in the driver's side wheel well with two ports. It's pretty big, opaque bottle that looks like a juice container or coffee pot filler. On my car the whole shebang was missing including a clamp to hold the thing in place. The clamp is NLA and may be hard to source. I used a heavy duty bungee cord and a block of 2"x 4" to wedge it in. I found a used "bottle" from jr@retroautomotiveproducts.com for about $80. Upon closer inspection I determined that all the associated tubing was shot, so I replaced it. There are several places to source evap control tubing and most will tell you what and what it cannot be used for. It's pretty inexpensive and you'll need two sizes all of which is detailed in the PET diagrams.

I decided not to replace the braded lines that exit the charcoal canister and end up in the CIS as they looked OK and the job looked too hard!!

At the bottom of the page I have zero gas smell now and feel I've added a measure of safety to boot.

Best,

Tom

[wayner]

I read where Michel Keyser ( speed merchant author ) had his race car burst into flames when fuel from that missing system got onto a hot brake rotor

[grizzfan]

Wayner posts:

I read where Michel Keyser ( speed merchant author ) had his race car burst into flames when fuel from that missing system got onto a hot brake rotor

I can visualize that happening. However so much of mine was either gone or disconnected that the probability for that exact problem was remote. All the fumes were collecting around the under frunk dash collector. But that's not good either!!!

Tom

[wayner]

Imagine a spark in the frunk!

Yikes...

[Neilnaz]

I had none of the original system in my car when I bought it and the petrol tank just vented straight to atmosphere. The garage always smelt of petrol and the car was a fire hazard. I didn't realise this straight away but decided to investigate.

I decided to vent the tank via a (modern(ish) from a VW Golf Mk IV) carbon canister and then a small air filter. The result is that there are no petrol fumes. The original fittings are very hard to come by especially in NZ.

Cheers, Neil