xrotaryguy

My 84 gsl keeps killing fuel pumps. It has killed a stock 80 pump, some sort of carter pump, 3 universal pumps of varying pressures and columes, and a holly red. It seems like the pumps just get hot and die after about 50 miles on the tripometer. I have a clean tank from a SA, new rubber lines throughout, no leak in the pick up tube in the tank, A rebuilt and beautifully performing carb, new fuel filter, and I can blow through the hard lines with out too much effort. Oh yeah and the pump is running directly off the leading coil with a fuse in line which was supposed to eliminate the chance of this being a fuel pump relay. Im running out of ideas as to what could be causing this. I think I will blow through the lines on my 80 and see how hard they are to blow through as compared to the 84. and maybe try it with the filter in the right way again. It kills pumps wether the filter is in right or not. I didnt find this out on purpose.
any ideas sould be appreciated,
thanks,
Brian

Siraniko

iTrader: (13)

It seem ur frying the F/P motors. Ever thought of running a stand alone wires to the pump? Also a hidden F/P switch is a better than an alarm...A thief cant drive far and he will eventually ditch the car.
.
.
.
.
.
.
.
.
.

.
.
.
.
.
.
.
.
.
.
. in the middle of the street.

bkm_rx7

Ya know, i asked this same question a while back. My '84 gsl (maybe its just this model???) has been doing the same thing. It burned up 3 carter fuel pumps and the stock one...

Anyways, i went with a MSD electronic fuel pump and Mallory fuel pressure regulator and have not had problems since...

Can somebody answer why our cars burn up the pumps?

xrotaryguy

Im glad im not the only one. I was starting to think that i was just retarded or something. I mean its not like its a complicated fuel delivery system or anything. Aside from the carb that is... I am thinking of putting a resistor in line to the pump to see if that makes it run cooler and for longer. I might do an electronic ignition set up on my rx 4 so theres a donor for the resistor lol. how long has the msd pump been working?

bkm_rx7

For the longest time i thought i was the only one too!!! Glad to hear im not the only one around here with bad luck, lol.

As far as the MSD that i have, it ran for a week or so on my car, then i bought a new holley carburetor and punched a hole in my old radiator on accident, so im kinda at a stopping point at the moment. But ive been very pleased with it and i doubt it will end up burning out.

xrotaryguy

My holley red lasted over a week but then died too. So Im still not real optamistic. I am thinking that perhaps I have a blockage in the return line. Maybe the fuel pump is dead heading too much. We shall see

mcnannay

im thinking the exact same thing, i was reading fb II's post on his blockage problem, he didn't even know he had a blocked return line until he tried sticking a coat hangar down there....

im willing to bet that is the problem...the return line, causing the pump to work really hard and burn up....

we were able to blow air through my lil bros lines (bkm rx7) but so was fb II, he even shot gas out of the filler neck when he did it....and he can't even get a coat hanger 10 inches past the return line??? so i don't think air is doing the trick. I would suggest clearing out your return lines or running new ones...which is what im suggesting to you too brenden!

what a freaking headache that crap is, i was stranded once about 3 miles from home because his fuel pump died for the 4th time....pissed me off

good luck, lets try to figure this one out and let us know what happens with it!

xrotaryguy

that was my next project. Its reassuring to know that someone is thinking the same thing. But hey. What else can I think? I have done EVERYTHING else. lol. I bought a bunch of 5/16 and 1/4 inch brake line yesterday at work and now I am just waiting for the right moment. You know for work to not interfere and for the gf to be ok with me in the garage and for jupiter to lign up with the clingons circling uranus. Im also reassured by the fact that someone else could blow through their lines and still had clogged lines. I think I see the moons aligning now.
Brian

xrotaryguy

so far I have gotten the fuel delivery line replaced and the old one seemed fine so I really hopw its the return line.

IanS

iTrader: (4)

If air wont work, here is an idea/explanation:

clamp air nozzle to water hose without female end
clamp fuel line (long piece) to hard line
clamp other end of fuel line to air nozzle
hook up water hose to water
give the air nozzle trigger a squeeze

I am saying use an air nozzle because they have a small outlet and would be easier to clamp to the fuel line. Also since air goes through and fluid doesnt, maybe you need to force fluid through it to get the chunk of crud out.

The_Dude

UI dunno but .. putting water .. in the fuel lines ? :S Isn't that a bad idea ? !? :S

xrotaryguy

Yeah I guess water is bad but its not like it would be in there for a long time or anything. I live in phoenix az so as soon as its in its evaporated again at 105 degrees in the garage. I am thinking that this really isnt the problem though. As improbable as it is hhat there are actualy other fuel delivery components on this car that can even be looked into I still cant find any blockage in these lines as I am replacing them. Not in the delivery or the return line. I think that I will put a resistor in in the harness to the pump before I drive it again just to try and conserve fuel pumps.
And if that doesnt work Im seriously thinking about rigging up some kind of dual pump system where the two pumps trade off. That way when one gets hot it shuts down and the other starts up. I think I could do it with a couple of relays and an adjustable temperature sending unit for an aftermatket radiator fan. That would be pretty cool. Its a rediculous idea really but I dont have any other ideas anymore.
I dunno maybe the tank is the problem. Has any one else ever used a SA tank in an FB Rx7? I cant imagine why there would be a problem but like I say Im running out of ideas.
How bout this... What is the best #%&*ing fuel pump on the face of the planet? Can I just put a kick *** fuel pump that will take what ever abuse this car is dishing out in it and call it good? Something better than a holley red cause I killed one of those. It lasted longer than all the rest but it still died in like a week or so. How bout a stock isuzu diesel pump from a 80 ford ranger. hahaha. Something... Anything! haha cause I dont think that this fuel line replacement thing is going to change anything.

xrotaryguy

Ok dudes, new lines are in and I have like 50 miles on this pump this time around. Thats 20 miles further than the last pump. Im hoping that my fiancee will stay around the house long for me to drive around on the freeway with my cell phone for a hundred miles or so and see what happens. Wish me luck

Ultralights

instead of using water, use metho/ kero or similar based solvents???

mcnannay

man i hope that cures your problem, because thats gonna be what we are going to do next on my bros car...run new lines

capri93

Use laquer(sp) thinner or if your looking for I high pressure pump get one from a ford powerstroke diesel but get braided steel lines befor running it to far or poof.

xrotaryguy

sorry man didnt cure the prob. I used this fuel pump about... I dunno 70 miles? not too good. I bought a balast resistor today and I fugure that will run the pump off about 8 volts. I cant think of anything else to do. everything from the tank to the carb and back again has now been repleced. Any more ideas? I also noticed that the volt meter reads almost 14 volts but thats not a bad thing for sure. I kinda figure that its cause the car doesnt get run much and so the battery is down a little. Do you think a bad voltage regulator could do it? how do you check a voltage regulator? Im sure its mentioned in the Hanes manual.

Rx7carl

This tells me 2 things. First off, is the pump located in the engine compartment? That will kill a pump quicker-n-****. They arent designed to pull that much head on the inlet side. Your killing it by over working it. Second, running it off the ign coil is causing it to run at a lower voltage than it needs to have as the coil will cause a voltage drop in the circut. You need a dedicated circut either off batt hot or ign hot (study the wiring diagram to see how the circuts are split up). And that pump needs to be as close to the tank as possible.

xrotaryguy

the proble was not cured. The pump only lasted about 70 miles. I am going to try putting a resister in the cuel pump circuit so that its getting about 8 volts instead of 12. Actually I think my regulator is putting out almost 14 all the time according to my dash guage. I dont think thats really too much. Especially since the car sits so much I kinda figure the battery needs a little charging when it finally does get driven and thats why it reads high. Maybe I should check my regulator. Or just toss another one in there. Is it the same as a SA regulator? have one of those lying around. I hope this works cause Im running out of fuel pumps haha. I'll have to start warrantying them again and you know that looks a little suspicious at auto zone

mar3

iTrader: (8)

I think Carl's hit it on the head...an electric pump CANNOT be installed under the hood...it needs to be as close to the fuel tank as possible and below the lowest point of the gas tank if at all possible...

rototiller1

your burning up your pumps due to a loss of fuel on the inlet side of the pump. The fuel cools the pump. I had this problem, the cause was sediment in the tank restricting flow to the pump, FLUSH the tank!

Rx7carl

Hijack- rototiller, your an A&P?

rototiller1

yes

xrotaryguy

can you guys see my last 2 posts cause I cant. Any how I keep trying to post that The fuel lines did not fix anything. I have installed a resistor in the fuel pump circuit. I am hoping that the pump is for some reason getting too much voltage. how much is too much? maybe my regulator is bad. even then though you wouldnt think say 15 volts instead of 13.5 would kill the thing. I dunno. We'll see I guess

xrotaryguy

Ok now I can see my newer posts and not my older ones. Weird. Any how I Hope that the tank isnt my problem cause this tank is the second one that I have had in the car. If I burn up this pump I will look into getting another tank... again