Fuel Spill

[76okievette]

Here is what happened, my 76 coupe sat in the gargare for about 3 weeks then when I went to drive it it started right up no problems but after I pulled out I noticed about a half gallon of gas had leaked out on the gargare floor. Car does not normally leak, no leaks before I started it and no leaks after or during the drive. I have let the car sit again for a week and will start it over the weekend to see if it does the same thing again, any ideas on what it could be?

 

[Phill]

if the gas that leaked out left a stain on the floor that should narrow it down as far as where to look. first time i read your post i thought you had said half a tank of gas. first thing i thought of was, he must have some teenagers.

 

[LVMYVT76]

could be a fuelpump, or a rubber hose leaking by the fuel pump or near the tank, could be the tank leaking. Need to know which end the fuel was at to help narrow the cause down.

 

[White75]

It's probalby a rubber hose that's dry rotted. Where was the puddle?
On ours, the leak was dripping onto the passenger side muffler and frame rail area. I replaced the 2 lines leading from the gas tank to the hard lines and both of them were pretty badly deteriorated.
To fix it, Drop the tank at least a foot or so to get at the lines, remove the passenger side taillights to get the lines where they go to the hard lines just above the muffler (unless you can remove the muffler as it will make it a little bit easier to reach too). replace the lines and the clamps as well (might as well since you're there)

If your leak is at the front it's probably near your fuel pump and those lines are pretty easy to replace. If it's still leaking around there, it could be the pump at that point, another easy fix. Luckily most of the lines between the tank and pump are hard lines. If you're leaking there, you'll have to replace those of course.
To help track the leak, use talcum powder dabbed on the lines to track where the leak is to narrow down which line it is (however if it's a rubber line, do yourself a favor and replace them all as they will all probably be deteriorated)

Your tank is probably OK but you can look at it when you drop it to see of there are any spots where you see residue from leaks, however, it would be leaking when standing still too if it was the tank. To test that, fill up the car with gas cans (don't drive to the station in the vette), if it leaks and the car hasn't run (causing the fuel to run through bad lines) then you have a hole in your tank. If you get your leak when the engine is on or notice it after the car is off, then it's your lines. Either way, siphon out as much as possible back into gas cans to make the tank lighter when you drop it (trust me, a full tank is heavy as hell)

 

[76okievette]

The puddle was at the front, so I will take a hard look at the fuel pump but it did not continue to leak which has me confused. So my thoughts are that pretty much rules out a busted line. Could the fuel pump "flood" and run over when first started up?
I have a good fire extinguisher and am keeping a close eye on it when I start the car.
Also watching my neighbor she has been eyeing my car lately.

Will start her up on Saturday and see if it happens again, am tring to sell the car so would love to get it fixed before anyone comes to look at it.

 

[LVMYVT76]

If it is the rubber hose by the fuel pump, that is a molded hose, be sure to order it as such, using fuel line hose will kink as the lines gets warm, as I learned from experience.

 

[White75]

The puddle was at the front, so I will take a hard look at the fuel pump but it did not continue to leak which has me confused. So my thoughts are that pretty much rules out a busted line. Could the fuel pump "flood" and run over when first started up?
I have a good fire extinguisher and am keeping a close eye on it when I start the car.
Also watching my neighbor she has been eyeing my car lately.

Will start her up on Saturday and see if it happens again, am tring to sell the car so would love to get it fixed before anyone comes to look at it.

It could still be a busted line. When the engine isn't running, fuel isn't flowing and there isn't the pressure that would cause the line to leak. Use the talcum powder method to trace the source of the leak.

The leak could also be your car crying for you not to sell her. Listen to her.

 

[76okievette]

It could still be a busted line. When the engine isn't running, fuel isn't flowing and there isn't the pressure that would cause the line to leak. Use the talcum powder method to trace the source of the leak.

The leak could also be your car crying for you not to sell her. Listen to her.

Thanks, I will check the fuel lines and pump this weekend, I think she is just jealous because I parked the new 08 vette next to her in the gargare

I will let you know what I find.

 

[76okievette]

Ok did it again this weekend but I was watching and the fuel was coming from the fuel pump, new one ordered and will install as soon as it arrives, any pointers and advice on the install, it seems pretty stright forward.
Thanks

 

[White75]

Ok did it again this weekend but I was watching and the fuel was coming from the fuel pump, new one ordered and will install as soon as it arrives, any pointers and advice on the install, it seems pretty stright forward.
Thanks

Cool. Glad you found it. I'd go ahead and replace the lines too.
One hint:
Preassemble the fuel pump with the backing plate, gaskets and bolts which will make it easier to keep the pushrod in the right position against the pump arm. You will also want to rotate the engine to move the cam lobe to the lowest position (whatever it's called )
I'm sure someone has a better explanation

 

[76okievette]

I read in one of the install manuals that you are suppose to remove the bolt in the lower rigth corner next to the forward bold holding the pump on and replace it with a longer bolt this is supposed to hold the push rod in place while you replace the pump, anyone heard of this?

 

[Vette79]

I read in one of the install manuals that you are suppose to remove the bolt in the lower rigth corner next to the forward bold holding the pump on and replace it with a longer bolt this is supposed to hold the push rod in place while you replace the pump, anyone heard of this?

It's not any of the four bolts that hold the pump in place. It's the bolt just below the AC bracket bolt on the front side of the motor where the fuel pump is. I replaced my fuel pump last spring and used plenty of pre-lube to keep it in place while installing the pushrod. As mentioned, used the pre-molded rubber fuel lines if you are replacing.

 

[Koop]

A half a gallon of gas is quite a bit. I hope you don't have a gas water heater or a gas dryer in your garage. Fire and fiberglass don't mix well (not to mention it might be bad for your garage and home).

 

[JohnZ]

I read in one of the install manuals that you are suppose to remove the bolt in the lower rigth corner next to the forward bold holding the pump on and replace it with a longer bolt this is supposed to hold the push rod in place while you replace the pump, anyone heard of this?

Photo below shows the location of the 3/8"-16 x 1/2" shipping bolt; remove it and use a 1"-long bolt temporarily to hold the fuel pump pushrod up in position while you change the pump. Just install it finger-tight (no wrench), and be sure to remove it and replace it with the correct 1/2"-long bolt, with sealer on the threads, BEFORE you start the engine.

If you set #1 at TDC on the compression stroke first, that will put the pushrod on the base circle of the cam lobe that drives it and it will simplify installation of the pump.

You'll also need to clamp off the rubber hose from the main line to the pump, or the contents of the tank will end up on the floor; I use a pair of plastic hose pliers with rounded jaws that won't damage the hose.

 

[White75]

Now that's a good find. Will save that for later
As far as a fuel line plug, a golf tee works well too and doesn't crimp the line.

Photo below shows the location of the 3/8"-16 x 1/2" shipping bolt; remove it and use a 1"-long bolt temporarily to hold the fuel pump pushrod up in position while you change the pump. Just install it finger-tight (no wrench), and be sure to remove it and replace it with the correct 1/2"-long bolt, with sealer on the threads, BEFORE you start the engine.

If you set #1 at TDC on the compression stroke first, that will put the pushrod on the base circle of the cam lobe that drives it and it will simplify installation of the pump.

You'll also need to clamp off the rubber hose from the main line to the pump, or the contents of the tank will end up on the floor; I use a pair of plastic hose pliers with rounded jaws that won't damage the hose.

 

[76okievette]

Great info due to the weather the pump has not arrived yet but I expect it today and nope to get it changed this weekend. Luck me I did not have any problems with the gas spill no fires just a bad smell for a day or two. Thanks all.

 

[THORIN]

One last thing. On my 76, same problem. It turned out someone had pulled the engine at some time and when they put it back in they reversed one of the mounting bolts. This bolt was close enough to the pump that it banged on it and broke the seals on the pump. So check to make sure nothing is close to the pump that might have caused this.

 

[73shark]

May be too late for you but discovered an easier way to hold the pump pushrod in while installing the pump than using the bolt in the front of the block. Put a small gob of grease on the end that goes in the block and it will stick to the cam lobe.