Fuel Feed Line Size

[harrycarry250]

Hello all,

As the name suggests...

Does anyone know the size of the steel fuel feed lines that run beneath the vehicle? My main pressurized feed line is rusted out right where it bends up to meet the engine bay join. Looking for the size of the line, fitting size, and flare style from anyone who has patched this before.

Thank you

 

[gsxr]

Don't know the exact size but it is metric with metric DIN/ISO bubble flare fittings, and I think it may be 6mm tubing...

 

[harrycarry250]

Just confirmed on my car it's 8mm if anyone else needs that.

 

[JC220]

Best to get 8mm Kunifer line and remake it from front to back. This was on my w140 recently. Hard to bend so I had to buy a Ridgid bender for this pipe.

 

[GRAEME JOHNSON]

That was interesting work when you replaced all those lines Joe
As the cars age its something we are all going to face
A lot of the steel fuel and SLS etc lines are NLA from Mercedes and the metal is hard to form
It would be good to know the correct sizes for the different systems, is cunifer even strong
enough for the pressures in the SLS ?
I tried to have a fuel line and some SLS lines made by cutting and flareing the steel fuel line
that was available and some longer steel brake lines but the garages tool was struggling with
the flares as the metal was so hard
It would be fantastic as a dedicated how to with sizes , fittings ,type of flare required etc for each of the different systems
Graeme Johnson

 

[JC220]

That was interesting work when you replaced all those lines Joe
As the cars age its something we are all going to face
A lot of the steel fuel and SLS etc lines are NLA from Mercedes and the metal is hard to form
It would be good to know the correct sizes for the different systems, is cunifer even strong
enough for the pressures in the SLS ?
I tried to have a fuel line and some SLS lines made by cutting and flareing the steel fuel line
that was available and some longer steel brake lines but the garages tool was struggling with
the flares as the metal was so hard
It would be fantastic as a dedicated how to with sizes , fittings ,type of flare required etc for each of the different systems
Graeme Johnson

Kunifer is a very strong pipe and resistant to road salts etc but I am unsure about using it on an SLS system. Do we know what the max pressure that system operates under?

8mm Kunifer pipe has a rated working pressure of 120bar.

I did have to buy a larger Kamasa brand flaring tool for these size of pipes and it does it with ease. As does the Ridgid bender but it is also spendy

On my cars I do work towards replacing all hard lines with Kunifer. Brake lines and fuel lines. Haven't had issues with SLS or ABC hard lines yet but would probably use it for those too if I could.