Removing old fuel lines

[In The Ten Ring]

It's high time I removed my old fuel line. I ASSUME the best way to remove the in-cab lines is upwards not downwards. Is that correct?

I also plan to use dishwashing detergent on those rubber grommets in the cab floor to get the lines through easier then remove the grommets and replace....what say you guys?

I would think one should put the new grommet into the floor THEN feed the line through it....does that sound right?

[AussieinNC]

I run a small tubing cutter thru the old line as it nears the cab floor, then again where the joiner is near the cross member....then just pull the old lines out....

I put the grommet on the in cab piece of new fuel pipe first, using dish soap on the grommet...place new pipe down into the cab floor then using a little dish soap, work the grommet into place...

Before joining the fuel pipe to the rubber joiner hose under the cab, I put the upper joiner piece in place between the pipe and the sender unit...this holds the upper line more or less in the finished location and lessens the need to redo clamps etc.

Always use fuel grade hoses and clamps...I always use screw clamps not spring clamps....

Good time to remind you to use a metal canister fuel filter, not plastic....

Have fun...

[External]

I'm new to my truck. Please tell me more about this plastic fuel filter and the rubber hoses.
I see metal lines running to rubber ones then plastic filter , more rubber hoses then finally metal again just before the carb.

[dmjlambert]

The stock routing is metal lines everywhere except 2 short pieces of rubber hose. One rubber hose piece is between the metal tube the runs along the frame and the metal tube that pokes down through the floor of the cab. The other rubber hose piece attaches the fuel pump to the metal tube the runs along the frame. Output of the fuel pump is a metal line that goes directly into the carburetor which has an internal filter. Fuel under pressure is best kept in all metal. Some non-stock type carburetors do not have internal fuel filters, and for those you can add a metal can type fuel filter in one of the short rubber lines, such as the one feeding the fuel pump.

I used to have those clear plastic inline filters, and I don't think they are worth anything. On mine, the filter broke loose from the inside and you could see it just floating around in there. Obviously it was not doing any filtering at that point. I had that happen with 3 of them. Now I'm just using the carburetor's built-in filter and not having any problems on my daily driver truck.

The problem with rubber hoses on the pressure side of the fuel pump is modern gas deteriorates rubber at an alarming rate, supposedly because of the ethanol in it. If you have a hose crack or one of those plastic inline filters crack, and it starts spraying gas all over your hot engine and exhaust manifolds, that is a fire hazard. A couple of short pieces of rubber hose attaching to the tube that runs along the frame has no pressure and if it cracks it is going to dribble straight down, stink up your garage or driveway or the road and most likely won't be as hazardous.

There are lots of opinions on how to do it right. A large number of new-to-the-forum first posts with pictures show a rubber fuel line running from the fuel pump to the carburetor with an inline plastic fuel filter posed right above the valve cover or exhaust manifold. Mine was one of those! I heard from some fine folks here that I ought to take care of that.

[External]

Thank you kind sir. I will also avoid the firestarter plastic filter.
Adding these items to the list of goodies.

[AussieinNC]

I strongly recommend that there is never a canister style fuel filter inserted between the fuel pump and the carb inlet...

A solid metal double flared pipe is the best and safest way to transfer the fuel from pump outlet to carb inlet.

When you use rubber connector hoses you should ensure the hose is clearly labelled for ethanol content fuel usage. Lower grade rubber hose for say water or vacuum is not suitable as it will deteriorate quickly.

Finally, always use fuel grade screw type clamps to secure the hoses to the pipes.

Stay safe and have fun...

[External]

I have one of those canisters you described. When I remove this, will the tiny one in my carb do the job?

[dmjlambert]

It's doing the job for me. I removed and looked at the filter after more than a year, and there was no visible contaminants. I replaced the filter and inlet gasket anyway just to have a fresh one. If you have a lot of crud in your old plastic see-through filter, you could probably put a fresh one of those between the frame tubing and the fuel pump inlet for a few weeks and see if you catch any more crud. If it catches more, you could switch to a metal one and replace it once per year. If you don't find any more crud in the new filter after a few weeks, just remove it and go with the stock setup. If you have not seen the sock on the end of the tube that goes down into your tank, you could remove the sending unit and inspect that sock. It is replaceable and does the job of basic filtering.

[External]

I'll check for the sock. Doubt it's there. But to hear that news about each little filter doing the job and lasting a year is great! Thanks for looking out for us and our fire traps. I'll fix it before it burns down!!