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Gents, 1989 Bronco, 302, EB. Nothing fancy. Mostly stock. Been my restoration project for the past year.

I'm going to tackle replacing the high pressure fuel pump on the rail and the fuel filter this weekend. I'm a year into owning the truck and haven't done that yet and they both look pretty old. Plus it is taking more than a few seconds to start up in the morning, but once the lines are primed all is well. Seems like a good idea to change them both at the same time and only smell like gasoline once.

Any wisdom or advice before I start this on Sunday? Looks pretty simple. Disconnect the battery, a few bolts, and the fuel lines. Try to catch the gas that spills. I also noticed a bleeder button to depressurize.

Thanks,

Sig
 

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I replaced my in tank fuel pump about 3 years ago on the 1993. I read a ton of reviews about what to purchase. The overall consensus on the interweb was to bite the bullet and use OEM replacement parts..... the entire OEM unit is around $185. I of course went my own way and bought the Chinese knock off pump only for around 35$ on Amazon. You can buy just the pump and install it into the existing module that contains the fuel sending and float... and since my gauge was fine... i just replaced the pump and purchased a metal float instead of the cheap plastic float that it had. I also purchased the quick disconnect fittings for the fuel lines since they can be a PAIN to remove. I'm glad I did because I destroyed one removing the line. I did the fuel pump access panel after dropping the tank. This was also a great move because the cheap pump only lasted 3 years. i have priced a replacement and this time will try the Bosch pump for 90$ on Amazon. We will see how long that one lasts... but it took me 10 minutes to pull with the access panel.


During my research i also found that the in tank pump is cooled by the gas. Since This was on my toy and not my daily driver I never had more than a 1/8 of a tank at any given time soooooo I might have added the fail rate by not keeping it cool enough.

The experts will be responding to let you know if you have the in tank or the two pump configuration.... but this is what I did on my 1993
 

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Replaced the high pressure pump on the rail (it was the original one) and the fuel filter today. Delphi pump and a Motorcraft filter. Project complete! Only challenge was the wires that connect to the pump. Had to change them over from the push on type to eye rings for the new pump.

However now the truck won't start. By that I mean it cranks but doesn't catch. I turned the key to the "On" position five times to prime the pump before trying to start. I can hear the normal sounds of the pump turning on. I'm reluctant to just run the starter for a long period of time.

Is there something I'm missing here? Should I just try starting it longer?
 

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Just double checked the fuel line connections. Re-connected the clips on filter and pump. No leaks. Just tried starting it again. Won't start. Let it crank for about 7 seconds. The rail pump is working. I hear it turning before and after crank, but fuel is clearly not making it to the engine.
 

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Yo Siggy,
Is spark present while it's turning over at normal speed?
Pull vacuum line to Fuel Pressure Regulator, if any gas or aroma THEREOF, replace FPR


On a cold engine, while cranking see if there is good pressure at fuel rail schrader valve, KOEO should be 35-45 PSI

Following from 1989 Ford Bronco EVTM, Emissions (yellowish/red book cover) & Pre-Delivery Manuals, Partial via mrnewland1 in Google Drive @
1989 Service manual - Google Drive
163044

163045
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"
Checking for fuel involves two separate tests. One is to check that the fuel pump is functioning and supplying the correct amount of pressure.

The other test is making sure that the PCM is activating the fuel injectors. This can easily be accomplished by using a noid light to check for these On/Off activation pulses the PCM sends to the injectors.

Now, what makes testing the fuel pump pretty easy, is that your Ford pickup (van, SUV) has a Schrader valve located on the fuel injector rail to which you can attach a fuel pressure gauge. So, let's say you attached a fuel pressure gauge, you'll get one of two results:

For a step-by-step explanation on how to test the fuel pump, check out this tutorial: How To Test The Fuel Pump (Ford 4.9L, 5.0L, 5.8L).

NOTE: You can run down to your local AutoZone or O'Reilly Auto Parts and rent one or, you can buy one online. You can check out the following link: Actron CP7838 Professional Fuel Pressure Tester


CASE 1: Fuel pressure is at specification This result confirms that the fuel pump is OK and doing its part. Also, this test result confirms that the following components are OK too:

  1. Fuel pump fuse.
  2. Fuel pump relay.
  3. Fuel pump inertia switch.
And so, there's no need to spend time testing them or money replacing them.

CASE 2: Fuel pressure is not present. This usually means that the pump has failed, but not always. I would recommend testing/checking the following before condemning the fuel pump:

  1. The fuel pump inertia switch.
    1. Checking to see if the inertia switch has tripped is very important, before condemning the fuel pump.
    2. If the inertia switch has been tripped, the fuel pump will not power up. So checking it and resetting it (if it has tripped) will save you from replacing a good fuel pump.
  2. Fuel pump power circuit.
 

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So after reading through a whole bunch of other posts I think the fuel pressure regulator may be the culprit. Before replacing the pump and filter it would take more than a few seconds to start in the morning, but after that everything was normal. Going to the store to buy a regulator now.
 

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So i did smell some fuel odor from the FPR vacuum line. I have now changed the Fuel pressure regulator and it still won't start. BTW those three little screws that hold in the FPR are a bugger to get out!

To recap the fuel system work. I replaced the fuel reservoir back in Dec 19 due to a leaking O-ring. Replaced the EGR solenoid in April when I finally replaced all the vacuum lines. Then decided to replace the pump & filter because it was taking more than a few seconds to start in the morning. Replaced the rail mounted fuel pump and fuel filter this morning. No leaks. Cranks, but doesn't start. Replaced the Fuel Pressure regulator. No improvement. Cranks, but Doesn't start.

I can hear the fuel pump kick on when I turn the key. Somehow It's like changing out the filter and pump de-primed the system so much that it won't start again. I think if I could get the lines primed again things would work.
 

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Did you check pressure on the rail like Al suggested? Just depress the valve stem with a towel or rag and see if gas is present. If it is, it sounds like it’s either an injector issue or something unrelated.

I see you had to redo the electrical connections. I’m unaware how many there are, but could the pump be running backward, or is the pump installed directionally correct? Just spitballing here.
 

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Did you check pressure on the rail like Al suggested? Just depress the valve stem with a towel or rag and see if gas is present. If it is, it sounds like it’s either an injector issue or something unrelated.

I see you had to redo the electrical connections. I’m unaware how many there are, but could the pump be running backward, or is the pump installed directionally correct? Just spitballing here.
The pump is DC power based Soo don’t think it is possible for it to be installed with reverse connections. Shouldn’t matter.

didn’t check the pressure at the rail yet. I need to locate the valve stem. Tomorrow I’ll probably take it all apart and reassemble.
 

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The pump is DC power based Soo don’t think it is possible for it to be installed with reverse connections. Shouldn’t matter.

didn’t check the pressure at the rail yet. I need to locate the valve stem. Tomorrow I’ll probably take it all apart and reassemble.
Yes it does matter. Just think about how your window motors reverse direction by reversing polarity. That may not be your problem, but if you reverse the polarity to the pump motor, it will run in reverse.
 

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Yes it does matter. Just think about how your window motors reverse direction by reversing polarity. That may not be your problem, but if you reverse the polarity to the pump motor, it will run in reverse.
I'll swap the wires this morning and see what happens.
 

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Yo Siggy,
Schrader valve is on driver side fuel rail, FWD of FPR;
163104
 

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Fixed it! The new pump was wired backwards. As soon as I swapped the wires, and re-primed it, it started right up. I may have ended up replacing the Fuel Pressure regulator for nothing, but glad that I did. Thanks for the trouble shooting everyone.
 

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Yo Siggy,
Great!
 
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