Fuel Pump - Replacement Engine

backporch · Dec 29, 2018

Replacement engine is in. Have everything connected but braided gas line. Was going to energize the fuel pump and blow some fuel through that line into a gas can. Would like to pump the gallon or two of year old gas from the tank and start with a fresh few gallons of fuel.

Turned the key the first notch many times and no gas. Had my daughter turn the key while I put my ear to the tank... no noise.

I don't know much of anything about this truck.. Bought as a project so I never saw it run. Looking for ideas what I can check for before I need to pull the pump.

I tried turning the key with the clutch depressed... not depressed.

The owner's manual says I should be able to tell if the inertia switch was triggered? no indication on the dash visible. The truck was flat bed towed but not dropped or bumped in any strange way.

The fuel pump fuse (20A) looks good and I swapped a working horn relay with the fuel pump relay.

I believe that I reconnected every connection from the harness back to where it should be.

Anyone have any suggestions?

Only noise it makes is a loud click by the upper intake manifold which may be a normal noise

RonD · Dec 29, 2018

Is this a 1999 Ranger 4.0l?

Fuel pump relay should click closed for 2 seconds when key is turned on, then click open

Put your finger on it and have someone turn key on and off to see if that relay is working

If relay is not working then check PCM/EEC Relay and PCM/EEC Fuse
PCM Relay should click closed with key on and stay closed until key is off, it powers the fuel pump relay
PCM relay also power computer(PCM), fuel injectors and most solenoids

If Fuel pump relay clicks closed with key on then you need to check inertia switch
Its in passenger side foot well or behind passenger side kick panel
Small, usually black, box with a red button on top, red button is for reset
Just above carpet on firewall or high in kick panel
With key on it should show 5-8volts on BOTH connectors, thats monitor voltage from the computer NOT power for the fuel pump.

If fuel pump relay is working, FP fuse is good(swap it), and inertia switch is OK, then pull the bed back and replace fuel pump

You can run a 12volt wire from Battery + to the inertia switch's Pink/black stripe wire and see if fuel pump comes on
The pink wire runs directly to the pump in the tank

The fuel pump can only run for 2 seconds with key on, its a safety feature, in case of an accident, once engine RPMs are at 400 or higher fuel pump relay will close again and fuel pump will be on until key off or RPMs drop below 400
So to pump fuel from the tank you may want to use the 12volt jumper wire to inertia switch or...............

You can pull out the FP relay and put a jumper between 30 and 87 slots, key on or off doesn't matter
Slots seen here: https://www.delcity.net/images/output-for-a-relay.jpg

Connecting 30 and 87 together is what the relay does when it closes

backporch · Dec 29, 2018

Right. 99 4.0L Manual Trans 4wd.

I understand most of what you said. Great information.

Pulling the fuel pump is a last resort for me. Sounds like jumping the fuel pump relay will be an easy way to determine if the pump has crapped out.

Will start looking at this again tomorrow.

Thanks

backporch · Dec 30, 2018

relay pins

Had to get a younger set of eyes to see all the detail on the relay, but if you lay the relay down so the prongs face you and the schematic faces up, the pins are numbered, from left to right 3,5 (larger prongs) and, on the right, top to bottom 1,4,2.

That means that the low current wires that activate the relay will be connected to the outside prongs of the set of three, 1 and 2. When no power is applied, the prongs 3 and 4 are connected. When 1-2 is powered, the solenoid connects 3 to 5.

The short that I need to do to ignore the relay is prongs 3 and 5, which makes sense because they are carrying the higher current through thicker wires for a high power demand accessory.

RonD · Dec 30, 2018

Yes, Ford in that year used 3 and 5 as numbering for fuel pump power pass thru

1 and 2 to activate relay

Industry standard
85 and 86 are to activate relay
30 and 87 are to pass power to device
87A is to pass power when relay is off, this would be #4 in Ford lay out but not used in this setup

The inertia switch is between relay and fuel pump, so jumper at relay doesn't check inertia switch

backporch · Dec 30, 2018

First Observations

With the ignition off, I ran a jumper from pin 3 to 5 and nothing happened. Put the same jumper between 3 and 5 on the horn relay and that worked.

On the fuel pump relay, pin 3 had 12v.

I also looked at the inertia switch and it was not activated. Do those ever go bad? I can swap out the one from the explorer or jumper that harness connection.

backporch · Dec 31, 2018

Going to swap out the inertia switch although I have only read that a failing inertia switch triggers too often. Have a fuel pump and filter on order.

RonD · Jan 1, 2019

You can jumper the inertia switch and then jumper 3 and 5 again

Yes, reads like fuel pump motor has failed

Removing or sliding back the bed is the best way to change fuel pump assembly for DIY
Remove 3 screws for filler and 6 bed bolts, unplug tail lights
You can also tilt the bed up, Google: Ford Ranger fuel pump replacement video

If you have a lift and transmission jack then dropping the tank is what a shop would do, but getting it back in is very very hard without the jack on wheels, hooking up the hoses and wiring is a tight squeeze

backporch · Jan 1, 2019

I started preparing for pulling the bed. I had the gas tank lose weeks ago while I was working with the brake lines, but it didn't seem like it could be easily lowered without stressing the connections. I also didn't remove the driveshaft.

The bed won't be easy either. I had to pull off the tonneau cover, remove the stuff I was storing in the back. Go to the dr after I threw out my back moving the crap. When I recover, I have what looks like it might be a factory plastic bed liner to remove. The 6 bolts holding the bed look ok from underneath except for the rearmost pair. They are rusted badly. All got PB Blaster.

More fun in a week or so.

Not the best start to 2019

Bgunner · Jan 1, 2019

When the fuel pump on my 94 was replaced it was easier to slide the bed back than drop the tank so IMO you're going at it the best way. Although my 94 came from Virginia so there is very little rust on any of the bolts so it really was easy to get the bolts out and not snap the those slip on nuts that they used on mine.

backporch · Jan 9, 2019

Gas Line Clip

Just when you get to a point where you think the worst is over.

trying to pull my fuel pump I broke the retaining ring with a chisel. Should have tried the giant pliers first. I am going to give it a whirl to gorilla glue the ring and maybe reinstall with a large oring around the outside.... if that fits.

Bigger issue is the fuel line with the clip that needs the ford tool. That won't come off worth a damn. Looks like there is a fair amount of crap that got up into the fitting over the years. I tried to run a small screwdriver and a pic in there. Sprayed some carb cleaner and crap came out... Still can't get the release too in far enough to release the clips. I fear there is crap under the tabs. Any suggestions?

Bgunner · Jan 10, 2019

I recommend replacing the ring instead of trying to fix it. If it does not seal then you can end up with a Evap code then have to pull the tank or bed to get at it again.

I've had good luck using a punch on the metal rings and large channel locks for the plastic rings to remove them.

As for the spring clips on the fuel lines just keep cleaning and lubing them, they will eventually release.

backporch · Jan 17, 2019

Spring clip removed and engine started

I wish I could provide a good technique to get that clip off. After cleaning, spraying WD40 and trying to work all the clips with a pick, it finally just came off with some pressure while using the pick. I tried for a while on the fuel filter and gave up.

When I primed the pump and cranked the replacement engine it fired up and ran. There seemed to be a lot of dust kicked up at first. I was kind of surprised but this is the first vehicle i have had with a fan that is not electric, so that would not be moving at first. My first thought is that it was something with the new clutch but I never put the truck in gear.

It only had it running for less than a minute. I need to go back and add water/coolant. My plan was to add only distilled water, drain the radiator and then add full strength coolant and water to the remaining water in the right proportions

Fuel Pump - Replacement Engine

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