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Discussion Starter #1
I've been having starting problems. Most the time when I turn the key the engine will turn over but not fire. I'll crank it for a couple of seconds, stop, and when I try it again it will start right up.

I ran the fuel pump pressure test, and when I grounded the FP pin on the test plug, the pump kicks on and the pressure reads 40. But, as soon as I remove the ground the pressure drops to 0. With the engine running the pressure reads between 32-34, and when I remove the vacuum hose off the regulator it jumps up to 40.

The engine runs fine and idles smoothly at 650 in neutral, and although I didn't pull the return line to see if its leaking there, I'm pretty sure it's not the regulator or a leaking injector. So, I've come to the conclusion that the check valve in the fuel pump isn't working.

I'm not sure how the check valve works, but I was wondering if it could be gummed up. And, if it is, would something like SeaFoam or another cleaner, free the valve back up. I really don't want to have to drop the tank and change the pump. I've just read too many stories about getting 20 yr old fuel line couplings unconnected.:whiteflag
 

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Chillin on the Gulf Coast
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The check valve could be blocked open. I wouldn't think that it would be blocked with crud, but more something solid. There is a sock filter on the bottom of the pump housing that could have failed. I mean if that filter alone has not been changed in 20 something years... Its probably time to man up and fix this the right way.
 

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Discussion Starter #3
That's more of a "blind guess" than a "conclusion". ;)A really stout spring, a shaft, a pintle, & a molded plastic seat, operated by a diaphragm.Not likely, but this IS likely:

I really don't want to have to buy gas, but it's a fact of driving. :hahaStop reading stories & read this caption:

Somehow I knew when I saw that you posted to my thread that you'd say something like 'Stop reading stories & read this caption:' or Get Er Done.

But I have no shame, so beggin for someone to tell me I might not have to drop the tank came easily. And, by the way, it was not a "blind guess" maybe not an educated guess but certainly I must have been on the right track since you posted the instruction on pulling the pump and not the fuel rail.:haha
 

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Discussion Starter #4
Since you're apparently not gonna even pull the vacuum line off the regulator to check, what would be the point of giving you even-more-complicated instructions on changing it? You wanna go with the pump? There you go! ;) If you change the pump, and it doesn't help, and you come back asking about the regulator, I'll probably post instructions then.
Actually, I did pull the vacuum line, posted that in my initial post. the fuel pressure jumped to 40 lbs. I didn't mention that there was no gas smell in the hose, but there wasn't. The manual said to pull the return line from the fuel rail and plug it to see if the pressure would hold. but haven't done anything else yet.

Ended up having to work on my rear brakes after the brake adjuster cable broke and the lever and spring go stuck in the shoes and tore up the drum. The rest of my time has been used for Christmas shopping and putting up lights.

But, when I do get back to the fuel issue, I'm not really sure how I'm going to plug up the rail return line. Or, how I'm going to check for leaking injectors if plugging the line doesn't fix the problem. Until then I'll have to live with the fact that it's not going to start the first time I turn the key.
 

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I have a problem similar to yours. My fuel pump will run for 30sec. Or so then I will start will run fine but when I shut off then restart It runs for a long time still like it's loosing prime. There are no leaks. Where should I look first ?
 

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Discussion Starter #6
I have a problem similar to yours. My fuel pump will run for 30sec. Or so then I will start will run fine but when I shut off then restart It runs for a long time still like it's loosing prime. There are no leaks. Where should I look first ?
Doesn't actually sound like my problem. My pump maintains 40 lbs of pressure while the engine in running. It's just that it won't hold the pressure for more than a second once the engine isn't running.

Cold or Warm, when I turn the Key it won't start right away. I'll hold it for about 3 seconds, stop for a second and then try again. Then it will start almost immediately on the second try.

I'd start with a fuel pressure check. I don't believe that your pump should run that long. I can hear mine for a few seconds after I turn the key to ON. Then I think it stops until I turn the Key to Start. If it's working properly it should hold the pressure that builds up during the first few seconds that you have it set to ON. And, they the pump should start running again once you turn the Key to Start and the ECC detects the Dizzy is turning.

I think you need to be sure that what you think is happening with the pump is actually happening.
 
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