98 Tdi 110 Fuel line size

[uninformed]

Im adding a CAV filter/water seperator to my fuel system. That is, Im leaving the factory sedimenter in place, adding the CAV in between it and the fuel filter in the engine bay.

I will be mounting it to the back of my truck cab.

The CAV filter head has M12x1.5 threads. I can get hyd fittings with this and a dowty washer to seal on CAV face.

The stock LR fuel line is nylon tube of 10mm OD (aprox 8mm ID).

Will I have problems if I use 1/4" line from the sedimeter to the CAV, from CAV back to Nylon line?

For all the fittings I can find, its either 1/4 or 3/8~10mm. I have not been able to source any 5/16~8mm fittings.

Reason Is Im trying to avoid bulky fittings.

cheers
Serg

[uninformed]

Anyone?

[Ancient Mariner]

Why do you want 5/16" fittings are you going to run the return back to the filter
Tap the CAV 1/4 BSP and use a 1/4" bsp x 3/8 nylon union

AM

[uninformed]

Thanks Noel,

nice looking CAV you have there. Is it a off the shelf kit from Donaldson?

My route will be:

Fuel tank to LR sedimenter at rear left. (As per factory set up)
Sedimenter to my CAV along left chassis rail to left side, back of cab.
Cav, along the back of cab to right side chassis rail to pick up original fuel line.

Currently the LR fuel line goes from the sedimenter, across the chassis cross member then along the right side chassis rail to engine bay filter.

I also have some room restrictions. I need to come out of the CAV and use 90 bends/elbows straight away.

I did not think of retapping the existing thread. I certainly could give that a go but I would not produce as good a job as the machine that did it in the factory.

At this stage it looks like I can source some M12x1.5 to JIC-05 (1/2-20 thread) forged male to male 90 elbows. These wont be too bulky and I can bend some metal tube and get some fittings for the end. Hose from this metal tube to LR fuel line can be 10mm/3/8"

cheers
Serg

[uninformed]

Noel, that bsp-nylon compression fitting, does it have a male spigot that goes inside the nylon tube?

Is it a IFS brand by chance?

[Ancient Mariner]

Serg the fitting are Yorkshire TubeFit .you can use a spigot but is not required If you are using for air brakes or recovery points might be worth while:D

Noel