fuel leak

[chevy7072]

I have a fuel leak coming from a small rubber hose that connects the steel line coming from the fuel tank to the steel line that's attached to the frame rail (goes to the fuel pump)..Is there any issues that I need to know when replacing it?
I was thinking I'd clamp both sides of the hose and then cut it in the middle and remove one end at a time..just a little concerned on how much gas will come out

[cleszkie]

The end that runs to the tank will run until the tank is emptied to the point that the fuel level in the tank is even with the open end of the fuel line. When you open the end of the fuel line, it creates a syphon and the gas will flow.

[chevy7072]

Is it possible to change the hose without draining the tank first?
any idea what would be the best way to replace it?

[In The Ten Ring]

Originally Posted by chevy7072

I have a fuel leak coming from a small rubber hose that connects the steel line coming from the fuel tank to the steel line that's attached to the frame rail (goes to the fuel pump)..Is there any issues that I need to know when replacing it?
I was thinking I'd clamp both sides of the hose and then cut it in the middle and remove one end at a time..just a little concerned on how much gas will come out

Where exactly is this leak?

I am familiar with these lines as I replaced every inch of my supply line from tank to carb. Just to make sure, your leak is under the passenger side of the cab, where the piece that runs through the floor of the cab and over to the line that is attached to the frame rail?

You shouldn't have much fuel to spill out....I didn't have any spill at all but my truck had sat idle for 9 years before I took my lines apart. If there is a spill, it should only be as much as is in the vertical part of the lines. A rag to catch it should be sufficient. Be sure to be in a well-ventilated place (if inside a garage run a fan and make sure the door is open).

Never be under a vehicle without safety goggles on (rust can and will fall into your eyes). Keep all sources of ignition away. A friend with a CO2 fire extinguisher standing by is a good idea.

I suspect your hose connection has dry rotted and is cracked. It's safe to assume that has happened to each of the rubber hose connections (there are three such connections on the supply line plus those on the vent line if you have a vent line). You also might should suspect rust in all of the fuel system, which means replacing all supply lines, pump, gas tank, and possibly a carb rebuild.

I'd cut through the hose, catch any fuel in a rag, and cut the hose off with a carpenter's knife. I don't think you need worry that much about sparking.

Ugh...replacing fuel lines isn't that hard but you'll need a tube bender, flare kit, and I used poly armor tubing from NAPA. Some guys have used braided steel line and AN fittings from tank to pump and pump to carb but I only plan to use that from pump to carb.

If you replace your lines under your truck, put the original beside the new on a workbench and bend away. You don't have to be exact. You'll use 3/8th inch from tank through under floor and then 5/16 along the frame rail. I used a 3/8 to 5/16 brass union to match up the two different size hoses under the cab floor. I bought a Craftsman Double Flare kit for the bubble flares at the tube ends. Some guys said the tube ends didn't even need flaring as the OEM pump isn't such high pressure and they might be right. A bubble flare is easy to do though.

Anyone else?

[chevy7072]

yes, that's exactly where my leak is coming from.Not planning on replacing the metal fuel lines..not yet anyways ..but its nice talking to someone who has done it..appreciate your advice..thank you

[In The Ten Ring]

Welcome. I hope you don't have to go through a whole fuel line replacement, it can be a daunting process but not very hard once you have an idea what to do.

How stock is your truck? What year, engine, and carburetor? When did you drive it last?

[Stocker]

Welcome aboard! I recently changed my K20's fuel hoses including the one you are talking about.
Had only a small amount of leakage, not enough to be concerned about.
I just removed the old and slipped the new ones on, no problem.

[kwmech]

If this is a daily driver or you have recently driven this truck, when you pop that line off it could come out of there like a full flow drain. Have a drain pan close by and the new hose ready with clamps already installed and be prepared. It could go either way. Goggles on for the splash. Nothing as painful as gas in the eyes. I personally put a steel fuel filter there

[chevy7072]

Thanks everyone for sharing your knowledge...My truck is a 72.. I drive it about 4 days a week, about 40-60 miles a week..Tuesday was the last day I started it.The motor is a GM Performance HT383 (350) put in in 2001..about 55,000 on it. (still have the factory motor in the garage)..running a Edelbrock 600 carb, transmission has been rebuilt, aside from that its stock, even the front suspension, except from brakes and shocks of course. One more question..I haven't had a chance to look at it in the day light hours, but I'm guessing its a 3/8 inch hose?

[kwmech]

With a V8...yes,

[GASoline71]

Originally Posted by chevy7072

Is it possible to change the hose without draining the tank first?
any idea what would be the best way to replace it?

Just be fast...



Gary

[In The Ten Ring]

If a lot of fuel coming out is a possibility, you could get a siphoning pump from the local parts store and pump your gas tank empty (or near so) and into some gasoline cans.

Pour it back in when done.

[randy500]

Use an air blow gun to push the full back into the tank, take the cap off the tank first. I do it that way all the time, a friend once did it on a car with an in tank pump, blew the pump right off the pickup, had to pull the tank to reinstall it so don't use 90 pounds of air pressure.....

[panhead59]

Do it outside. Just have another person put their finger over the metal line when you take the old hose off. It's not under pressure. Or make a short hose that's plugged on one end and temp install. That'll quickly solve most spilling/leakage issues. Have the new line and clamps ready. Just do it fast as previously stated. Working with gas is dangerous and no fun.