Rubber Fuel Line

[FordFarmer]

Quick question, what size is the rubber line that goes from the plastic supply line to the mechanical fuel pump. I replaced it just a while ago with 5/16, that was my best guess. It didn't have the size markings on it and the ends were too stretched to take a good measurement. Went on the pump ok but sliding it over the plastic supply line was a bear, even using some soap to lube it up. Makes me wonder if I have the wrong size or my skinny ass just needs to try harder. It's barely on far enough for the clamp...barely.

Thanks

 

[savage]

Mine was 3/8 fuel line.

 

[broncodriver99]

Are you slipping the rubber directly over the plastic? I think there should be a nylon or brass barbed splice/union there. I think 5/16" is correct though.

 

[FordFarmer]

Mine was 3/8 fuel line.

That would likely make it easier because....

Are you slipping the rubber directly over the plastic? I think there should be a nylon or brass barbed splice/union there. I think 5/16" is correct though.

There is no barbed splice/union. Not saying there shouldn't be one, just that it's not there. Would it be be a compression fitting on the plastic side and the barbed male fitting on the rubber side?

 

[broncodriver99]

I just used a standard barbed on both sides when I did mine.

 

[alphamale]

Just replaced mine last week and sed 5/16". It was a real pain gettingbit over the air brake tbbing but even worse getting it over the nipple of the sending unit. Wish I would have thought of using soap to cut down on some of the friction. I also placed a small brass inser insidebthebplastic tubing tobhellp reinforce it against crushing under the hose clamps.

 

[DirtDonk]

I've always used 3/8" on all lines between the tank and pump, then 5/16" between pump and carburetor. This is for a stock pump and stock carburetor. Most aftermarket carbs use 3/8" fittings, so adapting is needed with a stock pump.

Paul

 

[FordFarmer]

I've always used 3/8" on all lines between the tank and pump, then 5/16" between pump and carburetor. This is for a stock pump and stock carburetor. Most aftermarket carbs use 3/8" fittings, so adapting is needed with a stock pump.

Paul

It is a stock pump and a stock (2100) carb. For a second opinion, do you slide the rubber hose over the plastic or use a fitting as previously mentioned? Is the plastic tube 5/16 also? Sorry for all the questions, normally I'd dive a little deeper myself but I've got a hand full of kids right now and a quick Q on the phone here or there is all I can manage right now!

 

[broncodriver99]

Just looked back through my receipts. When I redid mine I used 5/16" ID which is 3/8" OD. I see where I bought and returned 5/16" OD tubing as it was too small. I guess it depends which diameter they are quoting. I had noting to compare to as the PO of my Bronco ran soft rubber fuel line from the tank to the fuel pump, didn't work so well. %)

 

[DirtDonk]

For a second opinion, do you slide the rubber hose over the plastic or use a fitting as previously mentioned?

I've always just slid it over the plastic tubing myself. Never had a problem with that method. Although, if you can source a barbbed fitting that would work with the plastic tubing, that would seem to be an even better option.

Is the plastic tube 5/16 also?

Just visually I'd have to call it 3/8" from memory. Whether it's exactly that, or some metric equivalent (not common back then, but not unheard of either), the 3/8" ID rubber line seems to fit fairly well.
That holds true of the factory pump inlet sometimes as well. I say "sometimes" because I've seen different designs, where on one the inlet is a cast-in fitting that works with a 3/8" hose, and another one has a threaded hole that fits standard tubing ends. Depending on what fitting you find, you could use 3/8" or 5/16" in that application.

I'll have to go back and check out the one I just did a few weeks ago to remind me what type it was, but it took 3/8" for sure. This particular Bronco had a pre-bent line kit which is a 3/8" hard line with threaded barbbed fitting like this: http://www.wildhorses4x4.com/product/Fitting_3-8_BARB_1-4_NPT
I may have used the same type of fitting on the pump side, or I might have cut a 3/8" pre-flared hard line down to just a few inches to use as the pump inlet.
Don't remember, but it was something along those lines.

Paul

 

[alphamale]

I've always used 3/8" on all lines between the tank and pump, then 5/16" between pump and carburetor. This is for a stock pump and stock carburetor. Most aftermarket carbs use 3/8" fittings, so adapting is needed with a stock pump.

Paul

I did the same. The airbrake tubing was 3/8 and the rubber was 5/16. Everything in front of the pump went on fine. Putting the rubber hose over the air brake tubing and the nipple on the sending unit was a seriius PITA! Maybe I was supposed to use a different method to cinnect it but its running now!

 

[Rustytruck]

In 1974 the factory just slid the hose over the plastic tube. They used all 3/8 line. On the plastic end you should use 2 opposing hose clamps especially if using an electric pusher pump. 5/16" line was uses on the steel tube to the fuel filter on the carb.

 

[FordFarmer]

All is well with a 3/8 hose. Thanks for the quick help guys.