Overhaul complete fuel system - 77 suburban

[mistaake]

I have a new carburetor on the way, but I want to go way overkill and overhaul the whole fuel system. I don't want any junk to get into the new carb and I don't ever want this truck to leave me stranded again - at least for fuel issues

In addition to replacing the carburetor I am thinking about the following:

1. Fuel line. I haven't looked under the truck, but do I just run fuel hose (3/8? 5/16? what is the best size?) from the tank to the fuel filter to the fuel pump to the carburetor? Or is there anything more complex than that - like hard line or something? Any reason not just to run "regular" fuel line the whole way, or should I leave the hard line in place, and blow it out with a compressor or something?

2. Fuel pump. I see two options on RockAuto: 2 line and 3 line. Which one do I need? or would there be some benefit to switching to an electric fuel pump?

3. Fuel filter. I guess the new carb will come with a little filter on the carb. But can I put a real fuel filter in between the tank and the fuel pump? Should I just go to work and buy a random fuel filter with ends to connect hose to?

4. Fuel tank. Should I just let some gas run out into a clear container and look if it's pretty clean, and if it's fine, leave it alone? Or is there some way I can clean it without removing it entirely?

Thank you for any input!

 

[Georgeb]

If it were mine. I would flush the line out real good and use a Delco pump and a good inline filter after the pump as well as the carb filter. I did run for many yeas with just an inline filter and no carb filter tho. If you opt to replace line you will want to run 3/8" steel line as much as possible and as little hose as possible.

 

[Georgeb]

Also if there is crap in the tank you may want to carry a spare filter and the tools to change it.

 

[mistaake]

If it were mine. I would flush the line out real good and use a Delco pump and a good inline filter after the pump as well as the carb filter. I did run for many yeas with just an inline filter and no carb filter tho. If you opt to replace line you will want to run 3/8" steel line as much as possible and as little hose as possible.

Thanks for the input! So I should put an inline filter after the pump?

I figured out by looking at mine that I have the fuel pump with three lines. So I picked up one of those at work.

 

[Camar068]

I wasn't aware about the different fuel hoses until I came across da_raabi's post about it. If you're going to use any hose, I'd suggest getting the SAE 30R9 instead of the cheap stuff. Below is the link so you can read up on it.

http://www.gmsquarebody.com/forum/showthread.php?t=13208&highlight=fuel+hose

 

[yevgenievich]

As mentioned, use good hose, filter between pump and the carburator and blow out the hard lines(replace if damaged). If you have concerns on the fuel tank, drop it and clean. The filter sock on the end of the pick up tube might have fallen apart over the years.

 

[mistaake]

If it were mine. I would flush the line out real good and use a Delco pump and a good inline filter after the pump as well as the carb filter. I did run for many yeas with just an inline filter and no carb filter tho. If you opt to replace line you will want to run 3/8" steel line as much as possible and as little hose as possible.

what is the downside to just being lazy and running quality fuel hose the whole way? is it a safety issue? won't pass smog? loss of fuel pressure?

As mentioned, use good hose, filter between pump and the carburator and blow out the hard lines(replace if damaged). If you have concerns on the fuel tank, drop it and clean. The filter sock on the end of the pick up tube might have fallen apart over the years.

can i just connect some hose to the fuel pump, crank the engine, and spray it into a clear bottle and look at it, to determine whether the fuel in the tank is clean?

by the way the truck died/stalled on me in the middle of driving again yesterday. i checked under the hood and there was fuel everywhere coming out of the carburetor and forming a huge puddle of gasoline on the intake manifold and smoke coming out of carburetor. i don't know if it was a good idea but i sprayed some starting fluid into the carb put the air cleaner back on and held the gas petal to the floor and cranked. after doing that for a while (didn't do all the cranking at once because i don't want to kill the starter completely) it started up but there was a lot of dense gray and blue smoke out of exhaust.

hey, at least i know the fuel system up to the carb is fine, but i want to go through it anyway because i want the new carburetor to last forever

 

[Georgeb]

Running all hose is a safety issue in my opinion. It sounds to me like your float is sticking or you are getting crap in the needle and seat. Good filtration will be your best bet.

 

[mistaake]

Running all hose is a safety issue in my opinion. It sounds to me like your float is sticking or you are getting crap in the needle and seat. Good filtration will be your best bet.

yup we determined float is sticking and thats why new carb is on its way! i just want the new one to last forever

 

[yevgenievich]

You want as little hose as possible for safety/durability. Running the pump and seeing clear fuel give no indication on the condition of the pick up tube. It is probably fine, but if you want to be sure, the only way is to drop the tank.