Viton fuel line size

[benmack1]

I see several folks mentioning Viton fuel line replacements for use with biodiesel. Here is my dilmena-I don't know what all should be replaced and with what parts. Model 1993 300D 2.5L diesel - engine 602.962 (I think).


1) If I understand correctly, I can get the small injector to injector braided return lines from the frypower site - easy enough.

2) Should I replace the hose that connects the metal supply tube to the primary filter (and hose from filter to injector pump supply. (What size is the ID and OD and thickness I should get in Viton for this). Also soft viton or firm/hard viton (looks like there are two vitons according to McMaster-Carr catalog).

3) Same question as #2 for the return line hose from the secondary filter to the metal tube that runs back to the tank.

4) Does anyone sell a Viton tank line with the fitting attached or how do I replace this one? Does this need replacement typically? Is there something like this where the return re-enters the tank? (maybe I am confused but that is my understanding of the components - any corrections appreciated.)

Any advice appreciated on specs and what should be replaced.

[Biodiesel300TD]

MB seems to use 5/16" fuel line most of the time.

The supply line has a threaded fitting that goes into the tank screen. Unscrew the fitting and remove the hose from the car. There is a regular hose barb under the crimp on the end of the hose. If you cut the crimp off you can put a regular hose on with a hose clamp.

[Cervan]

viton does not expand so you must get the exact size correct, or you will end up breaking the line or not getting it on there.

[Biodiesel300TD]

Viton is very stretchy. The manufacturer claims it will stretch to twice it's length.

[Oldwolf]

I’m going to restart this post because it answers some of my questions about prepping a 602.962 for biodiesel use.

For now I’m replacing my 1993 vintage fuel line with new regular type fuel line. Hopefully this will last a few years with b20 and the occasional B100.

The supply line has a threaded fitting that goes into the tank screen. Unscrew the fitting and remove the hose from the car. There is a regular hose barb under the crimp on the end of the hose. If you cut the crimp off you can put a regular hose on with a hose clamp.

This is good to know and makes it much easier to change to Viton.

What about the fuel heater? Are there any seals that need to be changed in it?

The IP shutoff lever has an o-ring on the shaft. Is the Fryerpower “shut off valve o-ring” what I need?

Can the clear fuel lines after the final filter stay or should they be upgraded?

So it I am thinking that the tubing and seals that need upgrading on the 602.962 are:

1)Under hood black fuel lines
2)Braided injector return lines
3)IP shut off lever shaft o-ring
4)Fuel heater under hood seals ??????
5)Clear fuel lines ??????
6)Black line between fuel tank and hard line

If anyone can answer my questions I’d appreciate it.

[WINGAS]

Its not the clear fuel lines, but the o rings associated with them that should be done.

Yes, get with Jim on the return lines and Orings. Buy SAE 30R9 5/16" fuel line ( injector line as iots called) for the feed and returns.

On the 95, the o ring that went first is the one that went with the prefilter.

Also, extended bio use will cause the delivery valve seals to give up, so if you're in there, you might then clean the top of the IP to spotless, pull the hard lines and pull the DVs CAREFULLY so as not to disturb any of the springs/shims, etc, and put new ORINGs on. I plan on doing this to any "new" diesel I buy.