Fuel tank expansion tank

[Drew]

Hi all, does anyone know how this works? Part no. 16121117520

I have an E9 which simply vents vapour from the fuel tank down a single small bore hose to the atmosphere. On a warm day my garage stinks of fuel, and this shonky design may be the cause of fuel smells when driving also.

I recall that my 6er had three small bore ports by the tank filler neck, which connected to a plastic filter/tank, and no bad fuel smells. Wondering how easy it would be to refit the E24 expansion tank (or similar) to an E9?

In particular, why the three ports on the E24 filler neck? My E9 only has one, so if I needed three that would be an issue!

Thanks
Drew

[mdkohler]

Hi Drew, I just removed my tank from an '85 635. It does have 3 lines coming out of it like you thought.

3 lines tank

tank 3 lines.PNG (920.02 KiB) Viewed 2139 times

I don't know if this goes to it or not, but I did find a plastic box with 3 lines when the parts were removed. Maybe that is what you are talking about? If so, I have them both for sale if interested.

Breather box maybe?

breather maybe..PNG (674.54 KiB) Viewed 2139 times

[Drew]

Hi Marc, thanks for posting the piccies. Yes, that looks similar to what I remember. An E24 tank won't fit my car I'm afraid, but I have heard that some E9 owners braze on 2 more vent pipes (to get a total of 3) and then fit the plastic evap control vent canister.
I was hoping I could work out a way of doing this without that hard work.
If I knew what the tank did and how it did it I was hoping to rig up something similar using only the single vent pipe I have

Cheers
Drew