Mechanical fuel pump...or replace with electric

If you shitcan the mechanical fuel pump and put a new electric in the tank, you're done.
Not really possible.
The truck is an '83 and never came with a pump in the tank. The opening in the tank for the sending unit probably isn't even big enough. I don't really want to start hacking things any more than necessary, either.
 
It only takes a small bit of dirt in one of the valves of a mechanical pump to stop it from working, tank may not be rusted but that doesn't mean it's clean inside.
It needs to have a filter or at least a screen on the inlet tube before the fuel pump to prevent debris from getting in the valves.
 
Can you blow compressed air through the fuel line to the tank to clear a potential blockage. I would use a low pressure setting 20 psi sounds about right at the rubber line that hooks to the fuel pump. The electric rotary vane pumps I mentioned earlier are in line and can be mounted on the firewall the frame or fender well.
 
Can you blow compressed air through the fuel line to the tank to clear a potential blockage. I would use a low pressure setting 20 psi sounds about right at the rubber line that hooks to the fuel pump.
I can do that. And I will add a filter before the pump as suggested for good measure.
 
I can do that. And I will add a filter before the pump as suggested for good measure.
Just be careful you might even want to start at a lower pressure and Take Off your Gas Cap off so you don't get blow back from the fuel line. Better yet would be disconnecting the line from the tank altogether. I would not recommend putting a fuel filter before your fuel pump either to much restriction on the suction side.
 
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Unrelated. My old Volvo 240 wagon came from the factory with two pumps, one in the tank and one on the frame rail.

EFI? Ford built some of their earlier EFI stuff that way. My diesel has two pumps too, one little electric pump acting as a suction pump and the high pressure injection pump. Whats odd about the configuration, the electric pump is after the fuel filter. Most of the time you don't want restrictions on the inlet side just because its a lot more difficult to pull through a restriction than it is to push.
 
EFI? Ford built some of their earlier EFI stuff that way. My diesel has two pumps too, one little electric pump acting as a suction pump and the high pressure injection pump. Whats odd about the configuration, the electric pump is after the fuel filter. Most of the time you don't want restrictions on the inlet side just because its a lot more difficult to pull through a restriction than it is to push.
Yes, it was EFI.
I've had a few Rangers and a Bronco II with the dual pump setup. I believe my F250 has it, too. Only it has dual tanks, so three pumps to possibly go bad.:rolleyes:

That diesel Lincoln is a cool, rare car. I think I have only heard of/came across one in the whole time I've been into cars.

I've run across a lot of other odd ball diesel vehicles from the 80s. S10s, Rangers, Tempos, Escorts, Chevettes, etc. People usually want insane amounts of money for them because they are rare and get really good fuel mileage.
 
Don't believe I've heard of a diesel S10 before but I think they did make a diesel Luv with an Isuzu motor. Possibly the same motor used in the S10. I think the Ranger was a Mazda engine, so were most of the rest of Ford's offerings. All that was a response to CAFE standards. I don't know if it was intended to be a stop-gap until gasoline engines became more efficient or if it just didn't work out because of reliability and performance issues. Either way, gas motors got better.

It is a wierdo, not very many were made. Something like 1500 of the four door like mine, and around 2500 of the two door. You'd think it would be the other way since the two door was marketed as a sporty coupe.
 
electric fuel pumps are often subbed in where the engine has a mode (all out insane full throttle) where it can outsuck the 6-7psi of a mechy pump at speed and dry it out when you mash the gas from idle (another reason that old school street racers revved up before the flag dropped)

you do not need an in tank pump which may present problems (but often an early TBI EFI truck used the same tank and you can drop it in) but you should use a close to the tank pump, axial pumps have poor suck ability when air is present and gas WILL drain back down.

The two pump solutions ford used, was a LP pump in the tank, then a HP pump on the frame rail connected to the FDM which gave a small reserve for the engine in the case of a burp.

BUT! all these solutions had the following in common:

fuel prime. KOEO it spun up to bring some fuel pressure, and would not spin again until the engine was running (for the person who turns the key, enables the dash lights, but does not start until they finish putting on lipstick.)

force shutdown: in all cases they had an inertial switch to shut off fuel...connected to:

engine on sense. GM (and others) was simple, there was a second circuit at the oil pressure switch to keep the pump on. (oil pressure = engine run). turn off the car and you still hear the pump for a second as oil pressure dies (GM TBI comes to mind, ford EECIV killed power hard to the relay, regardless what oil pressure was.

this helps in the event of an accident and the oil pressure switch is shorted, which means run

but on some cars (GM TBI again) if the oil pressure switch sticks on (it happens/happened) then the pump runs all night and the battery dies.

so while you *can* hook up a pump based on 'hot in start or run', Id advise adding the fancy electronics for safety.
 
I don't think Chrysler ever fuel injected the slant six. That body style truck did end up with a throttle body 318 or 3.9 later, but that might require a tank swap to get the right hanger to mount a pump to.
 
I agree with just replacing the mechanical fuel pump, ditching the electric, and making sure the entire fuel system is clean. You may also want to rebuild and inspect the carb if it hasn't been done recently, and inspect/replace all fuel line and hose. If the truck sat for a while, rust in the tank is also a concern.. I like the idea of a pre-filter (go big, to minimize pressure drop across filter), or maybe even cleaning out the tank if it's bad.

That electric add-on sounds like a Band-Aid by some previous owner, I'd want it out of there if it were my truck. Dodge knew what they were doing when they designed it way back when.

The 390 in my 1968 ford pickup had a weak fuel pump, it also died when I punched it merging onto the freeway, like the story 4-2-7 told up above. I cranked it until enough fuel was pumped to fill the carb bowl, and then drove home as slow as possible.. it could keep up just enough to supply the engine at low RPM, but as soon as you opened the throttle, the carb would empty and the engine die. Of course it happened when it was freezing cold outside, but it wasn't a huge job to change it.

One of my mentors had an interesting way to check a mechanical fuel pump... pull the fuel line off the carburetor, put thumb over end of line, and get someone else to crank engine. You can feel it build up pressure, should be possible to spray fuel like a garden hose. No smoking! Actually, I wouldn't suggest for anyone ever to do this, but it does facilitate road-side troubleshooting!
 
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Don't believe I've heard of a diesel S10 before but I think they did make a diesel Luv with an Isuzu motor. Possibly the same motor used in the S10. I think the Ranger was a Mazda engine, so were most of the rest of Ford's offerings.
I think the S10 did use the same diesel engine as the LUV/Pup. The Ranger actually had two different diesel engines. A Perkins/Mazda NA 2.2 or a Mitsubishi turbo 2.3. I spent way too much time on the Ranger forums when I had the my Ranger and Bronco II.:D
 
I've run across a lot of other odd ball diesel vehicles from the 80s. S10s, Rangers, Tempos, Escorts, Chevettes, etc. People usually want insane amounts of money for them because they are rare and get really good fuel mileage.

I drive an 86 Toyota diesel pickup, it sure does get good mileage, I'm consistently getting under 7 liters per 100 km (34mpg), which is really fantastic for a 30 year old truck which is basically all mechanical. I also like the sound of the little diesel, and the lack of any speeding tickets!
 
I agree with just replacing the mechanical fuel pump, ditching the electric, and making sure the entire fuel system is clean. You may also want to rebuild and inspect the carb if it hasn't been done recently, and inspect/replace all fuel line and hose. If the truck sat for a while, rust in the tank is also a concern.. I like the idea of a pre-filter (go big, to minimize pressure drop across filter), or maybe even cleaning out the tank if it's bad.
I probably will just replace the pump with another, since it won't cost anything, and go from there. As I mentioned, I already ditched the electric pump, replaced all the rubber lines, replaced the fuel filter, and rebuilt the carb. I just replaced the pump as a good measure when I did the rest. The tank is plastic, so no rust, and should be pretty clean inside. The old fuel filter was clean inside when I replaced it. The truck ran very good for around 1000 miles after I did the work. The new pump just took a crap all of the sudden.
 
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I probably will just replace the pump with another, since it won't cost anything, and go from there. As I mentioned, I already ditched the electric pump, replaced all the rubber lines, replaced the fuel filter, and rebuilt the carb. I just replaced the pump as a good measure when I did the rest. The tank is plastic, so no rust, and should be pretty clean inside. The old fuel filter was clean inside when I replaced it. The truck ran very good for around 1000 miles after I did the work. The new pump just took a crap all of the sudden.

Oh jeez sorry I couldn't have read that worse, I just went back and re-read the original question. That's just bad luck, did you buy it at a place like autozone? Some aftermarket parts are just garbage.
 
The fact that somebody already had to put an electric pump in the supply line tells me there's some other issue that no one took the time for fix the right way. You might have something floating around in the tank that's restricting the pickup tube, or the tube itself might be bad.

Might be time to drop the tank and see what's going on.
 
Oh jeez sorry I couldn't have read that worse, I just went back and re-read the original question. That's just bad luck, did you buy it at a place like autozone? Some aftermarket parts are just garbage.
No problem.
O'Rielly's, so probably the same difference. I know all too well about garbage aftermarket parts. I've been through enough of them.:mad: It sucks when they are all that's available sometimes.
 
No problem.
O'Rielly's, so probably the same difference. I know all too well about garbage aftermarket parts. I've been through enough of them.:mad: It sucks when they are all that's available sometimes.

I've had pretty decent luck with rockauto.com for hard to find stuff, they usually have some decent non china sourced parts along with the cheap stuff, and shipping is fast.
 
The fact that somebody already had to put an electric pump in the supply line tells me there's some other issue that no one took the time for fix the right way. You might have something floating around in the tank that's restricting the pickup tube, or the tube itself might be bad.

Might be time to drop the tank and see what's going on.
For right now, I'm just going to blame that on a brainless previous owner. If you saw some of the other things they did to this truck, you'd understand.:no: If I have a problem after the pump is replaced, then I'll be forced to drop the tank.
 
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