Bad electric fuel pump?

Had this happen yesterday and today; drove for a short while and the car wants to die like it's starved for gas, rev it up and it runs bad, but runs.. after a minute or two, or if it does stall and I let it site for a minute, then it's fine.
Today drove it and made a stop for about 30 min, start it up and got about 3 blocks away before it starts again, this time it did die, but i got it started and again was fine, but I noticed that it wants to die after hard acceleration, then give it a minute or two and it's fine again.

I also noticed that I need to pump the hell out of it when it is cold or has not ran for awhile.

The filter is new from last year...

 

How old is your gas?

 

gas is from last week and today.

 

Is your electric fuel pump making any noises that are different from normal humming?

 

Is NY an ethanol state? Plays hell with electric fuel pumps.

 

I would think an electric pump would not bleed off fuel after sitting, and even if it did, it would be a matter of seconds before it pumped up the fuel and the engine started up. And kept running.

does the pump feel hot when it shuts off? What happens when you undo the line, and run the pump? How is the flow?

It sounds like its heating up and has an intermittent open, causing it to shut off or lose performance when hot. Next time it dies, spray the fuel pump with brake cleaner or computer component cleaner. It will cool off right away with that.

If it fires right up, there is your problem. Cooling it off causes the internal break to go back together. when it heats up, it expands and causes an open.

As always, make sure there are no fuel leaks, bad hoses, or electrical connections that need attention.

You could always swap out the pump to see if it the problem or not. You should always have a spare.

 

Where is the pump located on your vehicle?

 

Under the floor on the rear, about 2 feet from the tank.

 

I think DesertRatRodder hit it on the head. The reason I asked about location is that I had a electric pump under the hood one time and it would vapor lock. Since then, I have learned that location was wrong for many reasons. Let us know what you find out.

 

I assume you have a carb and no EFI. What make fuel pump is it? I What you are experiencing isn't a typical fuel pump failure mode. It certainly sounds like a fuel system problem though.

 

What kind of pump is it? I had hell with carter once, went to holly with a regulator and solved it.

 

You might want to check the pickup screen in the tank (if you have one). They get gummed up and start to plug up after sitting for awhile causing the same problems you have discribed. Good Luck!

 

The pump is from the 70's/80's and has been on the car sitting fro 20 years so it only may have 10 years on it, if that, and I cannot tell the make, it clicks the whole time even through the rough running.

I thought vapor lock but the motor did not get hot and it happens rather quicly after it sat.

 

Had it happen again this am, started fine and got down the street a few houses and she would not idle, but if I kept my foot down, or kept it choked it would run, roughly..
Needed to floor it to start and had to push it into the garage, once I let it sit for a minute it started right up and idled fine.

Does an electric pump die slowly or does it just quit?
Car never got hot at all....

 

If you can choke the car or pump it and keep it running, it's not the fuel pump. If it were the fuel pump, choking it and pumping it would be extremely momentary, like buying 30 seconds. Then you would've exhausted the little bit of gas remaining in the bowls and accel pump and the car will just die.

Since you need to take the carb off anyway, unhook the fuel line, route it into a coffee can and have somebody hit the key. You ought to get a half cup or more within a ten count.

Personally, I think you have debris in the carb bowl that's moving and covering up different holes at different times. Or possibly a needle & seat with boogers. The symptoms are more in line the way you describe them.

That thing got one of those cheapie chrome fuel lines? When the chrome flakes off the inside, the resulting symptom is dead nuts on what you describe.

good luck

 

Change your fuel filter, sounds like you are picking up rust/ crud from your fuel tank.
When you start moveing ,crud in your tank gets stired up and blocks the fuel pick up
and filter.


...........Jack

 

Electric pumps usually give problems when the brushes hang up in their holders due to gum up. Also has the brushes wear down they have a tendecy to bounce and loose contact. I have had pumps stop and I hit buttom of tank with a mallet and they start up again, this is a sign it must be replaced.

 

I looked into the tank last year when I replaced the fuel guage float and it was pretty clean,
I did have a needle problem last year, and put 2 new holley needles in.

I have a handheld vacuum/pressure guage and I will put that on the fuel line to see what I have.

I have 2 fuel filters on it, one before the pump and one before the carb, the fuel line is steel line and rubber, rubber from the tank through the filter and to the steel line that runs to the carb and rubber from that line to the fuel filter and to the carb.

I believe that the pump is an old Stewart Warner, from a conversation with a club member, based on description and sound.
I picked a new one up anyway since I would need a new one soon.

I put one of those glass filters on last year when the same thing happened so I could see fuel flow, and when it acts like it does it appears that the flow is low...

 

i've ran into the same problem in a later model f.i. system that left me stranded 6 hrs from home. it would start up fine then after five min. of idling it would die and not start then cool down it would start alright then go down the road for a bit then die. then it finally gave up. The problem was it would heat up then not produce the volume and light on the pressure and the car would die. it was the pump.

 

Perhaps it is a stupid question.

Any chance you recently replaced the gas cap with something non vented?

Could it be developing a vacuum situation in the tank? An easy test is to get it start sputtering and pop the cap off.

Also replace all the filters.

If you are using rubber between the tank and pump, replace it with a section of metal line with short rubber connections. You could have a bad line.

 

The filler is a sealed unit from Rock Valley with a sealed cap, I have a vent tapped into the fillet and run up from the neck inside the fender with steel line, the rubber is new, I had the same problem last year that went away, and it is only short pieces.

 

Time to clean the lines and replace the filters. After that replace the pump with a spare if you have one or get a new one. If problem still exists than attack the carb.

I have a Stewart Warner pump that is about 20 years old and runs good. I do carry a spare just in case. Ethanol will totally screw up your rubber pieces and gaskets over time, so refreshing those parts with parts that are not subject to ethanol failure might be good way to go as preventive maintenance.

I also run two inline fuel filters, one standard size between the tank and the pump and a biggie up front under the hood. They tend to catch all the trash.

 

I think shifty shifterton is on to something, random blockage in the carb maybe trash or old varnish.clean the carb and use air to blow out all passages.

 

I'm thinking about this and I have had this problem for awhile but is disappears, I rebuilt the carb last year with all new gaskets needles etc, all new rubber from last year with new filters from last year, with less than 200 miles on all...

All are the same symptom, except the needle was stuck and I could see gas just pouring out of the carb, but at least 3 or 4 or more times over the last 2 years, and each one I thought was something else.

I am going to check the fuel pressure tonight to see what's what

 

Ran my pressure guage off of the gas line, it showed 6.4 psi steady, it took a good 30 seconds to get there...

Not sure if my pressure guage is good since it sits at 2.5 instead of 0 with nothing hooked.

Took the primary and secondary bowls off, and replaced both needles, cleaned everything up and re set the floats.

Took the glass filter apart cleaned everything up and put back in, blew air through the line from the filter to the carb too.

put back together and ran down the street and...same thing wants to die, and will not idle, was running fine until I tromped on it. Barely got it home.
So I get the new fuel pump tomorrow will see if it makes a difference.

 

I would check filters and check for water in gas first.

 

Well, I got the new electric fuel pump and put it on today, and pulled the old one.

It is/was a Bendix cylindrical style with a replaceable filter in the canister. I could not read it since it was covered in grease/undercoating, but oncve removed I could see what it was.

I believe they were popular in the 60's and from the looks of the filter inside it it may not have been changed since then.
I cannot imagine how it worked for so long.

Tomorrow I get a new filter and line for before the pump and I hope to notice a difference.

 

Sounds like the nasty clogged filter could be your culprit. Maybe in the past it was intermitent because it would clog, then enough pressure would build to unclog it, but now it is just cluster-clogged to the max. Hopefully this fixes it. I absolutely hate chasing shit like this. I feel for ya.

Rudy