Fuel Pump Leaking
Thread Starter
Racer
Joined: Apr 2000
Posts: 279
Likes: 0
From: MOONACHIE NJ
Fuel Pump Leaking
HI.Went for a ride yesterday and smelled gas pulled over and looked under to see a few drops of gas leaking from the fuel pump.The leak is coming from the connection or at least it looks like from were the line from the gas tank runs into the fuel pump.I checked the connection and it was tight.Was wondering when it was put back on if there is supposed to be any sealer or something on the threads..The line from the pump to the carb is ok.It was fine before the rebuild.Thanks for any help. >STW<Frank
Tech Contributor
Joined: Aug 1999
Posts: 15,173
Likes: 3,982
From: Connecticut, USA
Re: Fuel Pump Leaking (NJ74STINGRAY)
Frank,
Do you have the rubber "s" hose from the main gas line to the pump or a differant connection to the pump? Also is it the stock Delco pump or an aftermarket one? A lot of the aftermarket mechanical pumps have a gasket around them do you can reposition the fitting to your car application- maybe it's leaking from that point?
Gary
Do you have the rubber "s" hose from the main gas line to the pump or a differant connection to the pump? Also is it the stock Delco pump or an aftermarket one? A lot of the aftermarket mechanical pumps have a gasket around them do you can reposition the fitting to your car application- maybe it's leaking from that point?
Gary
Melting Slicks
Joined: Apr 2001
Posts: 2,280
Likes: 0
From: colorado springs CO
Re: Fuel Pump Leaking (NJ74STINGRAY)
usually the fuel lines get very cracked with age.....
get some long lengths of line ~4 feet or soo... and when you disconnect the old lines put the 4 foot lines on it and let it hang over the fender... since the lines are soo long and going up and over the fender --then this is the same as plugging the lines...--although much easier..
now u can install new fuel pump in peace... might as well put a new one on while your there!!
u shouldnt need pipe sealer on the brass fittings, although some people do use thread tape on em...
get some long lengths of line ~4 feet or soo... and when you disconnect the old lines put the 4 foot lines on it and let it hang over the fender... since the lines are soo long and going up and over the fender --then this is the same as plugging the lines...--although much easier..
now u can install new fuel pump in peace... might as well put a new one on while your there!!
u shouldnt need pipe sealer on the brass fittings, although some people do use thread tape on em...
Drifting
Joined: Nov 2000
Posts: 1,390
Likes: 39
From: North Brunswick NJ
Re: Fuel Pump Leaking (gtr1999)
Frank,
If you have the original style fuel pump, you will have a steel flare nut line running from the pump to the carb and a rubber line running from the frame rail to the pump. If the rubber line is old and the spring clamps are the original, I woud replace the all the rubber parts and the clamps. I would be carefull that the gas is not coming from the weap hole in the pump. If this is the case it tells you that the pump diaphram is leaking and the pump needs replacing. I would also check the oil for any gas leaking into the oil. Before you remove any of the gas lines you need to pinch off the fuel flow from the tank as gravity will give you a constant flow of gas,especially if the tank is full, this can be dangerous. Obviously now open flames or smoking when doing this job.
Regards
Ed
If you have the original style fuel pump, you will have a steel flare nut line running from the pump to the carb and a rubber line running from the frame rail to the pump. If the rubber line is old and the spring clamps are the original, I woud replace the all the rubber parts and the clamps. I would be carefull that the gas is not coming from the weap hole in the pump. If this is the case it tells you that the pump diaphram is leaking and the pump needs replacing. I would also check the oil for any gas leaking into the oil. Before you remove any of the gas lines you need to pinch off the fuel flow from the tank as gravity will give you a constant flow of gas,especially if the tank is full, this can be dangerous. Obviously now open flames or smoking when doing this job.
Regards
Ed
Thread Starter
Racer
Joined: Apr 2000
Posts: 279
Likes: 0
From: MOONACHIE NJ
Re: Fuel Pump Leaking (ED DINAPOLI)
HI Guy's,Just crawled out from under the car,not much room on sides of garage.Checked the rubber hoses and clamps look fine,the pump to carb line>METAL< has a drip coming from the flange connection from the pump to the carb.Loosened it up and then retightned it.Ed the oil does smell like gas and has a feel to it liek it is not as thick as it should be.Looks like an orginal style pump.Is the pump shot.
Drifting
Joined: Nov 2000
Posts: 1,390
Likes: 39
From: North Brunswick NJ
Re: Fuel Pump Leaking (NJ74STINGRAY)
Frank,
If you are getteing gas in your oil ,it sounds like the pump is leaking. You will need to replace the pump if this is the case. You need to very carefull with a gas leak in an enclosed garage. Make sure you disconnect the battery ,keep all open flames and elcetrical appliances away from the area. You will also need to change your oil. Good luck.
Ed
If you are getteing gas in your oil ,it sounds like the pump is leaking. You will need to replace the pump if this is the case. You need to very carefull with a gas leak in an enclosed garage. Make sure you disconnect the battery ,keep all open flames and elcetrical appliances away from the area. You will also need to change your oil. Good luck.
Ed
Thread Starter
Racer
Joined: Apr 2000
Posts: 279
Likes: 0
From: MOONACHIE NJ
Re: Fuel Pump Leaking (ED DINAPOLI)
Thanks Ed,I will give my mechanic a call tomm and see when he can do it.To cold and like you said I don't want to mess around with it in an attached garage.Figures the only thing the engine rebuilder did not replace.Any recomandations on a pump or just go back to stock one.Thanks All for your replies.Frank
Drifting
Joined: Nov 2000
Posts: 1,390
Likes: 39
From: North Brunswick NJ
Re: Fuel Pump Leaking (NJ74STINGRAY)
Frank,
Sorry for your trouble. If you are not going to modify your engine, I would go with the straight GM replacement. Make sure you dont get an LT1 pump as it will not have a return line. Best of luck.
Ed
Sorry for your trouble. If you are not going to modify your engine, I would go with the straight GM replacement. Make sure you dont get an LT1 pump as it will not have a return line. Best of luck.
Ed
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Tech Contributor
Joined: Aug 1999
Posts: 15,173
Likes: 3,982
From: Connecticut, USA
Re: Fuel Pump Leaking (NJ74STINGRAY)
Hi Frank I just checked back and see you found the problem. I would use a Delco original type pump vs the aftermarket performance type. I have the Delco on my 72 and a Carter mechanical on the 69. I had some installation problems routing the gas hoses on the 69 where the Delco bolted rioght in and everything fit well. I remember changing the pump in a garage during the winter too with about 2' space between the car and wall-PITA! I was 20 years younger and 30 lbs lighter then so that helped! :D I picked up the original type pumps lines and filter last year so I'll be changing the 69 back when I start rebuilding it.
If all goes well I look forward to Sat.
If all goes well I look forward to Sat.
Team Owner
Joined: Aug 1999
Posts: 28,707
Likes: 4
From: Fort Mill, SC via NJ
Re: Fuel Pump Leaking (gtr1999)
Frank I remember someone suggesting changing the pump when we were at the rebuilder :blueangel: :cheers:
Ritchie did say the pump looked fairly new though.
Ritchie did say the pump looked fairly new though.
Thread Starter
Racer
Joined: Apr 2000
Posts: 279
Likes: 0
From: MOONACHIE NJ
Re: Fuel Pump Leaking (CWUin82)
HI JIm,How you doing?You got much snow? Yes jim alway's something. Joe asked the rebuilder and the pump LOOKED brand new.Good thing I did not get stuck.As always thank's for the help guy's! See you on sat Jim & Gary
Instructor
Joined: Jun 2001
Posts: 131
Likes: 0
Re: Fuel Pump Leaking (NJ74STINGRAY)
Yup. Like the other guys have said: It probably the rubber fuel lines that are cracked. If they're hard and don't flex easily, replace them. New clips too. The tines broke off my mine when I tried to get them off. Besides, the new clips are shiny and red! :conehead
Personally, I'm in the Teflon thread tape camp. Also, the GM assembly manuals refer to a rubber sealant/lubricant when you put the rubber lines on the fuel pump.
I've heard that using a little bit of transmission fluid to help seal the rubber hose on the fitting helps. The theory is that the fluid would "burn" off and seal the connection. Fact or fiction? Maybe the Forum knows. :)
-Rexx
Personally, I'm in the Teflon thread tape camp. Also, the GM assembly manuals refer to a rubber sealant/lubricant when you put the rubber lines on the fuel pump.
I've heard that using a little bit of transmission fluid to help seal the rubber hose on the fitting helps. The theory is that the fluid would "burn" off and seal the connection. Fact or fiction? Maybe the Forum knows. :)
-Rexx
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
Re: Fuel Pump Leaking (NJ74STINGRAY)
The fuel pump is designed so that there is a vent running to the outside of the pump casing. There needs to be one so that the diaphram can move. It's also convenient so that when the diaphram gets a hole in it you will immediately see fuel leaking out. I would recommend replacing the fuel pump with a stock replacement and see if that stops the leak. No fuel should be getting into the oil though, but there's always a first.
