Tank to pump fuel hose diameter?

[Gunter]

1980 SC
It's the short hose from tank to pump with clamps.

What is the actual I.D.?

[kees]

I think it's 11.8 x 17.8 mm fuel line (12x18,5)

ID 11.8 mm

Bulk Fuel Line, (11.8mm X 17.8mm) 911/911 Turbo (1974-89)
Partnumber 999 181 168 50

The length is 90 mm.


Kees.

[squelch]

Don't know if it's the same, but on my '84 Carrera the inner diameter is 12mm and the outer diameter is 18mm.

[burgermeister]

I used 7/16" or 1/2" fuel line - I think I got the 7/16" to fit (snugly) on the tank, but I'm not positive that it fit on the fuel pump nubbin, in which case I would have used the 1/2" line....

Metric fuel line is difficult to procure in our neck of the woods.

[spuggy]

This might help, if your pump is one of these:

[burgermeister]

The conversions Bosch lists appear messed up ... 3/8" is 9.5mm in my book, and 1/2" is 12.7 mm (thus the ability to use a 1/2" wrench on a 13mm nut).