85 Vette Fuel Pump
Thread Starter
Cruising
Joined: Jan 2007
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85 Vette Fuel Pump
Hi all! I posted here for the first time almost 7 months ago but can't find thread? Car still isn't running but at least it cranks now because that was one of the two problems! My carpenter an x-stereo alarm guy figured it out in 10 minutes, something to do with the alarm! I think I have the other problem of not starting is faulty fuel pump! Don't hear it turn on when the key is first turned? A friend put his finger on the schrader valve and said yes there is fuel in there but he thought it should shoot out rather then seep out and he believes the fuel presssure should be about 40 pounds? So my question now is, do you have to pull the tank to replace pump?
Thanks in advance!
Car Freak or was that Car Fool for having too many cars? lol!!!
Thanks in advance!
Car Freak or was that Car Fool for having too many cars? lol!!!
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
You don't have to pull the tank, take off the fuel door by lifting it up and removing the screws under it. With that out of the way you will see a rubber boot, CAREFULLY take it out. It tears easily so be careful. Once the boot is out you can see the tank and all you have to do is take the screws out around the perimeter of the cover you see, remove the hoses noting where they came from for replacement. Just lift up on the cover and the fuel pump will come with it. Don't forget to replace the sock too. By far the easiest fuel pump R&R you will ever do.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
....easy to replace. Took me about 1/2 hour. Pay attention to which way the sock is on the pump and which way it is located in the tank.Fuel pressure for an 85 should be 36-40 PSI with the vacuum line to the fuel pressure regulator disconnected and plugged.
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Cruising
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Burning Brakes
Joined: Apr 2004
Posts: 762
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From: Huntington ma
when you open the fuel door you can see four small screws ( same as interior trim screws), in the corners of the base, that hold down the door and base assembly. Take out those four screws and the door/base will lift straight up and off. Now you can pry out the rubber boot. Then all is revealed...
The sock at the end of the pump Should come with the new pump - just make sure it's aligned the same way as the old one. You have to press the sock onto the end of the pump after you stick the pump onto the sender assy. It's also cheap insurance to replace the Pulsator (the connecting link between the pump itself and the line on the sending unit assembly) while you are in there... That is something you have to buy separately.
Oh - also not a bad idea to get a new Gasket for the sender assy when you buy the pump (it Won't come with the pump..). This is the square-ish shape gasket between the sender assy and the tank itself. You may be able to re-use the old one OK, or not..
The sock at the end of the pump Should come with the new pump - just make sure it's aligned the same way as the old one. You have to press the sock onto the end of the pump after you stick the pump onto the sender assy. It's also cheap insurance to replace the Pulsator (the connecting link between the pump itself and the line on the sending unit assembly) while you are in there... That is something you have to buy separately.
Oh - also not a bad idea to get a new Gasket for the sender assy when you buy the pump (it Won't come with the pump..). This is the square-ish shape gasket between the sender assy and the tank itself. You may be able to re-use the old one OK, or not..
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Don't just throw money at it. Diagnose and confirm that the pump is bad before you replace it. It is difficult to translate the length of the squirt out of the Schrader valve into psi. Check your fuel pressure with a gauge. You say you don't hear the pump run when you turn the key. You DO know that the pump is only supposed to run for about 2 seconds when you turn the key, right? Is there power to the pump? Is the fuse good? Is the fuel pump relay, relaying? How is the fuel filter?
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Intermediate
Joined: May 2005
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From: Toronto
Is the "Pulsator" the rectangular plastic piece with the 3 wires coming out of the top and bottom?
If so, I'd appreciate it if someone let me know where can I get one as well as a complete sending unit - they seem to be discontinued at AC Delco Canada.
Thanks.
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Cruising
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Le Mans Master
Joined: Sep 2006
Posts: 6,050
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
relay
Fuel pump relay is at the back of the left rocker cover on the firewall. just unclip the wire harness connector, and remove the two screws that hold it to the firewall. a 1/4" ratchet, a 9/32 socket with a universal and extension gets it good
Last edited by coupeguy2001; Jul 15, 2007 at 10:52 AM.
Thread Starter
Cruising
Joined: Jan 2007
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Thanks! Nice avatar! What color is that 85? charcoal?
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by Car Freak
Hi! I replaced the fuel filter! Is the fuel pump relay easier to replace then the pump itself and where exactly is it? I also checked fuses and they look to be good. Thanks
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Thread Starter
Cruising
Joined: Jan 2007
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Unbelievable. It isn't an either/or situation. You don't replace the easiest one to get to. You trouble shoot to determine what the problem is, and then you fix or replace the cause. Your FSM has a trouble shooting chart just for this problem, if you can't reason your way through it.
RACE ON!!!
RACE ON!!!
