Problem Dying

[enjr44]

He was using a loose fuse as a temporary jumper, which blew. I wasn't referring to the proper fuse for protecting the circuit.

And, I was referring to hooking the pump up to a battery for testing. Using the fuse for a jumper was a great idea however. It proved the problem was downstream.

 

[RB7 Ranger]

The pump is probably drawing excessive current, from being run low on fuel , The cheap aftermarket pumps cant take any abuse, the fuel is the coolant & lubricant for pump, I would put a quality pump in it (Motor Craft or Delphi) and don't run it low, the pig tail for the Inertia switch is available from Ford.
Change the ,
1 pump assy.
FP Relay
inertia sw. & pig tail
fuel filter

Do it once and be done
Hope this helps

 

[nbates55]

The 20 amp fuse in the box under the hood for the fuel pump had blown. I checked, 20 amp is what it calls for, so that was correct, altho seems a little large for a fuel pump to me.
The other fuse I used as a jumper at the inertia switch was gray, so I think it was only a 2 amp. I will trace the wires tomorrow from front to back as best I can to see if I find anything wrong. Had a 73 Vega one time and the big red wire from the alternator had rubbed against the mounting bracket til it shorted and shut the whole works down. Luckily, it was easily found.
Im hoping I can rework the "rack" the fuel pump is mounted in instead of $250 for a new one!

 

[nbates55]

It has a bed liner in it. I have considered cutting a hole in the floor of the bed, lol. They should have a removable plate bolted on in the bed of pick ups for that anyway.

 

[enjr44]

The 20 amp fuse in the box under the hood for the fuel pump had blown. I checked, 20 amp is what it calls for, so that was correct, altho seems a little large for a fuel pump to me!

Me, too. Especially, if they were going to be so cheap to put wires and connectors in there that will not handle a 20 amp short. Arcing in a fuel tank is not good at all.

Dummy engineers not talking to each other. Before sneak-circuit analysis was required in the test labs, I used to see it all the time in aerospace. We (in doing maintenance analysis) used to find stuff like this all the time (and sometimes it was the end user that found it when sh*t hit the fan).

 

[nbates55]

Well, O'reillys is going to replace the whole assembly. $275.00 worth. Still not for sure its the pump that caused it tho. Cant find anything really wrong with any wires anywhere else. I think I should replace the 20 amp fuse with a 10 amp in case theres still a problem when I put it back together. Hopefully that will blow before wires start melting.

 

[enjr44]

Good job and good on O'Reilly's, too.

 

[nbates55]

Well, this is weird. Their computer shows that this is the correct part, altho it has a fuel pressure regulator on it. Mine didnt. They dont even show a 99 Ranger as having a fuel pressure regulator at all. We didnt figure it would hurt anything, so guess Ill go with it. Thoughts?

 

[enjr44]

The 99 does indeed have a pressure regulator. It is part of the pump assembly in the tank.

 

[nbates55]

Stranger Still!

Mine didnt have a regulator. The rubber hose went straight out of the top of the fuel pump to the metal plate that sits on top of the tank. Truck always ran great. Possible somebody took it off at some point in the past and reworked it? If they did, it didnt hurt the running of it. Ive had the truck since 2012.

 

[nbates55]

Still have not fixed the truck. Found a bad connection in one of the partially melted wires going to the inertia switch. Also, the red button seems awfully floppy in that switch. You can push it down, but it just seems rattly and turn it upside down and the red button will just flop down. Just doesnt "feel" right. Bigger concern is a continuous half amp draw on the battery. Tank is still sitting on the ground, no pump hooked up yet. Charged the battery and put it on the truck this morning. By this afternoon, it was already down to 10.5 volts just sitting. Me and a friend hooked up my multimeter in series with the battery and he pulled fuses one at a time. Found 3 that would drop it from a half amp to a quarter amp draw. None were really "critical" fuses. Cigarette lighter, audio system, back up lights. Strange. Havent found any other melted wires, but they could easily be in a hidden place, if any. Thoughts?

 

[nbates55]

Still no progress on this truck. Im getting power as far as the inertia switch, but no way to tell if the switch is bad. Id just jumper it, but theres 3 wires. Whats the third one for?
I put everything else together and hooked up the new fuel pump assembly outside the tank. Nothing. Dead as a hammer. No idea what to try next.

 

[nbates55]

1999 2.5 Liter Fuel Pump Meltdown Update

UPDATE:
Well, after O'reilly ordering the wrong part, I finally got the new fuel pump sending unit in and assembly installed. Had to go to Pull-A-Part and get another inertia switch as the old one was a lil melty and bad. Im pumping fuel now, no problem. But now I have no spark at the spark plug wires. So something else must have melted when it all went bad. I had the truck running (roughly) a little bit just before the fuel pump wires melted in two 3 weeks ago.
No idea otherwise why Id have no spark. Fuses all check out as good. Dont know where any fusible links may be or if it even has any. I guess the computer is fried, because with my luck, it cant be anything simple or cheap.
I started another thread about the "no spark" situation as this thread seems to have died.
Need help!

 

[nbates55]

FINALLY got this truck running this afternoon. As noted earlier, I had replaced the entire fuel pump assembly in the tank and the inertia switch. Had gas, but then no spark. Finally figured out why the truck wasnt firing. Fuses. Not a bad fuse, but a missing fuse! A while back, my mechanic friend and I was hunting for more bad wires, like the ones that melted at the inertia switch. I was under the hood with an ohm meter in series with the hot side of the battery watching amp draw as he pulled and replaced the fuses in the fuse block by the drivers door. Did find 3 that were drawing power, but not a lot, so probably normal drain for computer, radio, etc.. We went thru them twice. Pulling and replacing. What happened was, theres about 4 sockets that have no fuse in them as they are for options thats not on this truck. Apparently he put one back in the wrong hole, instead of the hole it needed to be in. I didnt have my diagram with me today, but had plenty of new fuses, so I just stuck one in every hole in the fuse block. Tried it and it didnt turn a half a round and fired right up! Something SO simple. Always check the simplest and most obvious stuff first. Then check it two or three more times just to be sure!