Porsche Enthusiasts Club Forum

Hi All

The fuel breather tank ...the long black plastic one that is fitted in the rear wing above the wheel....

Does it actually do anything ?

The reason I ask is that today my car went through its annual MOT.

That tank had dropped and was rubbing on the rear tyre and after removing it , it had obviously been doing it for a while as its was split from the rubbing...

The metal pipe that runs round the back from it to the rear PU had rotted away years ago and I never bothered replacing it..

Its called an "Expansion Tank" in Pet 7 but I cannot really see the point in replacing it as the weather in the UK is rarely hot enough to allow fuel to expand if thats its purpose >>> ???

Any advice appreciated...after removing it , I filled my tank to the brim (£94 worth ) and there is no leaking or fuel smell at all...

I am inclined not to bother replacing it unless anyone knows better...

So is it worth replacing for new, plus all the metal breather piping at the rear or no point ???

All the best Brett

probably an emissions requirement in some territories, but if the mot boys are happy, and you don't have any probs with its deletion, then why bother

Hi Steve

I never thought of that lol

You may well be right as a guy on Rennlist says his American 928 hasnt got it at all...

All the best Brett

Hi

Number 14 in the Pet illustration is the part I am taking about and its big....around 20 inches long roughly....




All the best Brett

If the car has been running without it, I would be tempted to leave it. However, it is a braver man than me who knows better than Porsche engineering. I've sent an email to Simon Watson to see if he has one. If Simon phones you Brett, I told him about your requirement. He'll use the number on your signature, are you in work today?

Hi Lee

Yes I am at work, I am a bit of a workaholic...lol

I really cannot see it "having" to be there as it was hanging down, rubbing on the tyre and split...

If its for fuel "fumes" I cant see how it works as there is no return pipe....

All the best Brett

If you fill your petrol tank up to capacity with cold petrol then go for a long drive the petrol will warm up and expand. The tank is there to catch the expanded fuel and vapor.

Any excess fuel and vapor is dumped out through the tube behind the number plate. (27)

There is also a check valve. (19) Circled in photo.

I think it just acts as an extended fuel tank - the fuel returns by gravity when there is room for it.

Removing it could cost you some fuel and could be a safety risk (?) but then who fills their tank up that much anyway.

Ben

Hi

Good pictures, thanks

I think I will do without it,at least until I smell any fuel or see any leaks...

The long pipe (25) rotted away years ago so I dont think that tank matters much in the UK, although I could see the point of it in hot climates...

All the best Brett

I had a similar issue but after removing it I haven't noticed any difference or problems so I think you'll be ok without it.