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Carter Electric Fuel Pump Failure

62 Dart Convertible

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So just finished mounting new fuel tank, new 3/8" pickup/sender and new Carter P4070 electric fuel pump.

Worked great for about 15 min and pump decided to quit. Checked it over, seems electric motor is up the creek. Meter reads 20 - 30 k ohms and not steady.

Just chatted with Summit customer service guy. He reckons in 15 years there, he's never seen/heard one of these fail. Made me feel so lucky!? Oh well, he is sending another to me now.

My question -
I do plan on running a 1/4" return line with 0.050" orifice back to tank later. Is a return line a strict necessity with electric pumps or just a "nice to have" to prevent vapor lock? The Carter instructions do not mention a return line at all.

Carter P4070.jpg
 
I ran an Edelbrock Street electric pump 150 GPH. Failed after years of service. Replaced it with same, and it failed after about 150 miles. Summit has never heard of this before. Carried a spare pump for years, then went back to Mo Mopar hipo mechanical pump. Quiet and reliable.
 
I have been using the same Carter pump for over a year now with no problems. I installed a pre filter before the pump and a regular fuel filter close to the engine.
I did not run a return line.
 
they'll stick sometimes. that pump will only do 3 or 4lbs psi. they're fairly simple. take the top cover off and see if the armature is stuck. sometimes it can be free up with some wd40. sitting for long periods of time will let the gas gum up the works. i'd recommend a carter 6903 mech pump.
 
You may want to check out your power source. It mat not be getting enough poop which will kill it. Learned that one the hard way. If its piggy backed on another circuit, it may not be sufficient enough and may need its own.
 
These guys make some good points. I think you just got a clunker pump. I ran a Carter for 7-8 yrs. without a problem & so far my Holley blue (5 yrs.) seems fine & I've never run a return line. I "think" return lines are only necessary with fuel injection & high fuel flow where the pump can pump way more fuel than the injectors need so the excess is sent back to the tank rather than "dead heading" the pump.
 
Thanks for the great replies guys, very considered and appreciated! I will try to explain my rationale.

For until new pump arrives, I plumbed it back to mech pump, and all the drivability problems it had before are still there - I had hoped the new pickup might have cured things as the screen on the old one was partially blocked/broken, but it made no difference.

I went elec for 2 reasons -

1. When I don't drive it for a few weeks, the carbs are bone dry and I would near flatten the battery cranking it until it would fire.

2. Car vapor locks like a MF once it gets nice and warm under the hood. Not just on hot days either - yesterday was a barely warm spring day and I had to park it for 30 min to cool off just to get home.

So plan was/is elec pump, vapor return line to tank. I did consider a Carter 6903 mech pump with a return line, but it wouldn't solve problem 1 (though it probably would be better, the question is how much better?) I would have then also installed a elec solenoid pump in tandem to cure problem 1. I thought since I would have to run wiring/controls for that, I may as well go the whole hog and go the elec pump route. I am an Elec Tech so I know my AC/DC. (No pun intended - though I do feel like I have been on a Highway to Hell..) The electrics are solid - I ran chunky 2.5 sq mm (metric measure - sorry I don't know what #ga you'd call it) from C/B panel through timer/oil pressure relays under dash all way to pump - so it's getting 12V.

I did consider a pump pre-filter, but surely the screen on the new pickup should be all it needs?

I feel quite confident now that I just lucked out and got a dud pump and that it's premature failure isn't attributable to an installation problem.
 
So just finished mounting new fuel tank, new 3/8" pickup/sender and new Carter P4070 electric fuel pump.

Worked great for about 15 min and pump decided to quit. Checked it over, seems electric motor is up the creek. Meter reads 20 - 30 k ohms and not steady.

Just chatted with Summit customer service guy. He reckons in 15 years there, he's never seen/heard one of these fail. Made me feel so lucky!? Oh well, he is sending another to me now.

My question -
I do plan on running a 1/4" return line with 0.050" orifice back to tank later. Is a return line a strict necessity with electric pumps or just a "nice to have" to prevent vapor lock? The Carter instructions do not mention a return line at all.

View attachment 368065
Tech guys always say that "this is the first time I've heard of that". Return line not necessary, pump only puts out low pressure (for carb) and a return line would only reduce the fuel flow at higher eng output. Have a pump just like yours and first one failed in short order also. Parts store replaced w/ no questions. I used a fuel filter off of an 80s era corvette (can't remember exact year) between tank & pump that has 3/8" in & out. Filter is about 3X the size of a std fuel filter. I figured I needed that to insure that no debris gets into the pump since I'm running an old tank. I'm also nervous about the pump and don't wander far from home. Planning on going back to mech. I have the pump running off of a relay that has full voltage from a reliable source. Also have an impact switch wired into the circuit to kill pump in case of collision. If interested I'll try to find the # of the Corvette filter. Think I have it somewhere.
 
Electric pumps are push pumps so keep as low and close to the tank as possible and as quoted check voltage at pump and ground
 
Tech guys always say that "this is the first time I've heard of that". Return line not necessary, pump only puts out low pressure (for carb) and a return line would only reduce the fuel flow at higher eng output. Have a pump just like yours and first one failed in short order also. Parts store replaced w/ no questions. I used a fuel filter off of an 80s era corvette (can't remember exact year) between tank & pump that has 3/8" in & out. Filter is about 3X the size of a std fuel filter. I figured I needed that to insure that no debris gets into the pump since I'm running an old tank. I'm also nervous about the pump and don't wander far from home. Planning on going back to mech. I have the pump running off of a relay that has full voltage from a reliable source. Also have an impact switch wired into the circuit to kill pump in case of collision. If interested I'll try to find the # of the Corvette filter. Think I have it somewhere.

Hi KarNut46. I have brand new tank, and pickup/filter sock. The pump failure is totally not debris related so I don't think I need another filter. (I do have a new 3/8" Wix fuel filter I did consider installing...) I will be installing a return line (with 0.050" restrictor) from a vapor separating filter as the vapor lock I get is ridiculous - I need to keep the fuel moving and bleed off vapor using this -

WIX-33040.jpg

Electric pumps are push pumps so keep as low and close to the tank as possible and as quoted check voltage at pump and ground

Hi bm02tj
Pump suction is maybe 8" above pickup and 1" away from tank - Carter recommend no more than 24", and obviously less is better. I will be shifting/lowering new pump a few inches anyway to gain more clearance. Voltage is not an issue.
 
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Been using Carter electric pumps for years on street cars and racers.Using it as a pusher at he tank to the mechanical pump.Only once did I have one fail right out of the box.(Nothing is perfect) I like to run a before pump filter and a after at the carb.Also on street cars,installed a switch(and relay) to prime the carb after sitting for days.Turn it on for full throttle blasts and off letting the mechanical do the job for regular driving.
 
I always run an electric pump on my cars. One thing is yes you want the pump as low and close to the tank as you can get it. And fuel under pressure being pushed up to the carb will not vapor lock as easily as fuel being pulled up to the fuel pump on the eng under vacum. Having the fuel being pushed under pressure will help fight vapor lock a good bit. I have never had any vapor lock problems at all and I drive on some very hot days. Now the only problem I had was this pump gas fuel wanting to boil in the carb fuel bowls if the fuel gets to hot as the cheap pump gas of today with the ethanal in it will boil if the fuel gets around 190 to 200 degrees. And when it boils it will make it run rich as on my Holley 850 it will boil the fuel to push out the internal bowl vents right into the carb throat. Buts thats a different problem then vapor lock as running a wooden or phenolic spacer under the carb is big help to fight fuel boiling. It sounds like you want to run a return line like the factory did with the 3 nipple fuel filter as the third line went back to the tank through a restrictor in the filter to let vapor push out the return line and go back to the tank. I dont remember the size of the restrictor but the .050 you said I believe is about right and if the stock mechanical pump can handle it the electric pump should with no problem as at that small size it dont effect fuel pressure or volume. Many guys do run stronger pumps today and run a return line that bleeds off enough fuel to keep the fuel pressure correct but you need the right pump and fuel pressure regulator to run that setup. It also helps keep the fuel cooler by having some fuel always moving.I have run Holley pumps most of my life and I have seen 2 of them go up in the 40 some years I have fooled with cars. I would just install the new pump they send you and recheck my power and ground circuits. Good luck with it , Ron
 
I always run an electric pump on my cars. One thing is yes you want the pump as low and close to the tank as you can get it. And fuel under pressure being pushed up to the carb will not vapor lock as easily as fuel being pulled up to the fuel pump on the eng under vacum. Having the fuel being pushed under pressure will help fight vapor lock a good bit. I have never had any vapor lock problems at all and I drive on some very hot days. Now the only problem I had was this pump gas fuel wanting to boil in the carb fuel bowls if the fuel gets to hot as the cheap pump gas of today with the ethanal in it will boil if the fuel gets around 190 to 200 degrees. And when it boils it will make it run rich as on my Holley 850 it will boil the fuel to push out the internal bowl vents right into the carb throat. Buts thats a different problem then vapor lock as running a wooden or phenolic spacer under the carb is big help to fight fuel boiling. It sounds like you want to run a return line like the factory did with the 3 nipple fuel filter as the third line went back to the tank through a restrictor in the filter to let vapor push out the return line and go back to the tank. I dont remember the size of the restrictor but the .050 you said I believe is about right and if the stock mechanical pump can handle it the electric pump should with no problem as at that small size it dont effect fuel pressure or volume. Many guys do run stronger pumps today and run a return line that bleeds off enough fuel to keep the fuel pressure correct but you need the right pump and fuel pressure regulator to run that setup. It also helps keep the fuel cooler by having some fuel always moving.I have run Holley pumps most of my life and I have seen 2 of them go up in the 40 some years I have fooled with cars. I would just install the new pump they send you and recheck my power and ground circuits. Good luck with it , Ron

Hi Ron

I appreciate the reply! I really do hope the elec pump and return line do cure my vapor lock problems. New pump arrived yesterday, so no guessing what I'm doing this weekend?! I have a pair of 1/2" phenolic spacers I will be also installing soon to try keep the carbs cooler.
 
Electric pump did nothing to improve symptoms of hot restart, or pumping after car sets for a week or more. Zip. The Carter manual pump performs just as well,without the noise. A 1/2 inch spacer and wrapped fuel lines caused much improvement. Ehtanol boils before fuel even when car running at 180.
 
I've been thinking about an electric pump in my A100. When the truck sits for a few weeks, it takes forever to draw fuel up to the crab. I was thinking an electric pump would help push the fuel up, and reduce the time spent cranking 'dry'.
Since it's a truck, the noise for my application should be less of a concern. :thumbsup:
 
Hi Ron

I appreciate the reply! I really do hope the elec pump and return line do cure my vapor lock problems. New pump arrived yesterday, so no guessing what I'm doing this weekend?! I have a pair of 1/2" phenolic spacers I will be also installing soon to try keep the carbs cooler.



It will help as an electric pump pushing fuel from the tank under pressure will work better then any mech pump pulling fuel under pressure when it comes to fighting vapor lock. Just like why coolant is under pressure since 1 lb of pressure raises the boiling point of coolant 3 degrees. And this pump gas with ethanol makes it worse then it was years ago. The wood or phenolic spacer helps alot as even if your car runs 200 as long as the fuel in the carb bowl is kept cool enough (which it can boil at 180 with ethanal in the fuel) it wont boil. My buddies car was running about 185 on a hot day and he did not have any spacer under his carb and his fuel started boiling while we were in traffic at Carlisle as it was about 98 degrees outside. He did not know why his car was flooding out real bad but I knew what it was right away. But he had no wood or phenolic spacer and he also did not have his fuel line insulated at all. I also run my fuel line up inside the pass wheelwell to keep the fuel line away from heat as much as I can since I drive on the street alot. Ron
 
Been using Carter electric pumps for years on street cars and racers.Using it as a pusher at he tank to the mechanical pump.Only once did I have one fail right out of the box.(Nothing is perfect) I like to run a before pump filter and a after at the carb.Also on street cars,installed a switch(and relay) to prime the carb after sitting for days.Turn it on for full throttle blasts and off letting the mechanical do the job for regular driving.
I do the exact same thing. Works great. Lately, I've been using the electric all the time for regular driving as hard driving tends to suck the bowls dry with the mechanical only.
 
Electric pump did nothing to improve symptoms of hot restart, or pumping after car sets for a week or more. Zip. The Carter manual pump performs just as well,without the noise. A 1/2 inch spacer and wrapped fuel lines caused much improvement. Ehtanol boils before fuel even when car running at 180.



How can you say and electric pump did not help when car sits for a week. All you have to do is turn the key on and let the carb bowls fill if they went empty. You cant do that with a mech pump as you will have to crank the eng over for a bit to get fuel back in the carb bowls. Course my carb bowls dont go empty even after mine sits for a month. I still just hit the pedal a couple times and then crank it and it fires right up. But if you have problems with the bowls going dry of course an electric pump will save the hassle of having to crank the crap out of it to fill the carb bowls. Now if your carb bowls stay full for the week or so then it wont make any difference as to how it starts after it sits. But it sounds like you were saying your carb bowls get low on fuel when it sits for a week ? Ron
 
Hi Ron

I appreciate the reply! I really do hope the elec pump and return line do cure my vapor lock problems. New pump arrived yesterday, so no guessing what I'm doing this weekend?! I have a pair of 1/2" phenolic spacers I will be also installing soon to try keep the carbs cooler.


One thing I forgot to mention was when the factory had the vapor return line to the tank from the 3 port filter or vapor canister as some call it that they had a spring loaded valve in the tank where that vapor return line goes into the tank. The reason was to keep a small amount of pressure in that line so it wont let the line and filter go empty by draining the fuel back into the tank when the eng is off. Course if you use an electric pump you may be ok without that spring loaded check valve as if the filter or bowls drain back the vapor return line you can just wait a few seconds to crank it after turning the key and electric pump on. Some also use an oil pressure switch to work the electric fuel pump but if you do you can just wire a switch to bypass it to fill the carb before you crank the eng. Ron
 
One thing I forgot to mention was when the factory had the vapor return line to the tank from the 3 port filter or vapor canister as some call it that they had a spring loaded valve in the tank where that vapor return line goes into the tank. The reason was to keep a small amount of pressure in that line so it wont let the line and filter go empty by draining the fuel back into the tank when the eng is off. Course if you use an electric pump you may be ok without that spring loaded check valve as if the filter or bowls drain back the vapor return line you can just wait a few seconds to crank it after turning the key and electric pump on. Some also use an oil pressure switch to work the electric fuel pump but if you do you can just wire a switch to bypass it to fill the carb before you crank the eng. Ron

Great points you make Ron, thanks! I have put the replacement electric pump in and went out on a cruise last weekend. All went well - so far! I have not put return line in yet, but will during next week. For electrical control, when I turn the key to "on", an electronic timer energises pump for 10 seconds, then stops (plenty time to ensure bowls are filled). Then pump is energised during cranking, and again once started only if oil pressure light is "off". I cut into the dash loom and wired in a connector for my timer/relays to make it easy to remove if needed. Control systems are my "wheelhouse".
 
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