I need to replace a small section of fuel hose the large line between the Square filter (12 mm and my two-port Bosch fuel pump. I already replaced but used incorrect hose size 12.7mm/1/2"so was going to go with 11mm or 7/16"

Ever since replacing with the new line I have a horrendous noise coming from the pump so I am guessing though not sure that the line size is the problem since I did not have any noise before... nothing is kinked or losse that would cause any noise either.

I dont think the fuel is under pressure there and could use SAE R7 line which is rated for 50psi,

However, was looking for R9 line which seems to have better ethanol / chemical rating and is higher pressure 100 psi.

Any thoughts on R7 versus R9?

Í cannot seem to source any R9 line in 7/16" /. 11 mm

This is what i used on the latest one i did.

https://www.amazon.com/gp/product/B07S9DF58...=UTF8&psc=1

have quite a lot left over as i only needed a few inches.

That would work if you'd like to sell me a couple feet

Wish I knew the rating though because R9 would be best although R7 would work ... it says E85 gas so I'm sure it cannot be less than R7