Electric pump conversion

Olcbass

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Hello, I have a 1988 f250 7.3 idi 4wd. She keeps losing prime so I'm killing my batteries and starter trying to re prime. I want to delete the mechanical pump and put a facet pump in to replace it but I've noticed there's a lot of vacuum lines coming off of the fuel pump. Looks like its for the brake assist and the a/c heater and what not. Is there a way to bypass this or can I just put an auxiliary pump in just to prime it and keep the mechanical pump?
 

gnathv

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I think your looking at the wrong area maybe. The mechanical fuel pump is on the passenger side of the engine below the exhaust manifold. There should be 2 fuel lines. 1 rubber line coming into the pump and 1 metal line leaving the fuel pump going up to the filter housing on the top driver side of engine.
 

franklin2

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Hello, I have a 1988 f250 7.3 idi 4wd. She keeps losing prime so I'm killing my batteries and starter trying to re prime. I want to delete the mechanical pump and put a facet pump in to replace it but I've noticed there's a lot of vacuum lines coming off of the fuel pump. Looks like its for the brake assist and the a/c heater and what not. Is there a way to bypass this or can I just put an auxiliary pump in just to prime it and keep the mechanical pump?
Yes, I think you are looking at the vacuum pump, not the fuel pump. I am not against running a electric pump, I have one myself. But you should also work on finding your leak that is causing you to lose prime. You will find the electric pump will help, but the problem will not go completely away and over time will get worse even with the electric pump.
 

Olcbass

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So you would recommend replacing all of the fuel line from the tank to the fuel filter/separator with A/N fittings and braided hose? Instead of putting a band aid on it?
 

IDIBRONCO

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So you would recommend replacing all of the fuel line from the tank to the fuel filter/separator with A/N fittings and braided hose? Instead of putting a band aid on it?
Nobody said that. It was suggested that you find the leak and repair it. It isn't easy to do, but can be done. First off I would start by checking for wet or dirty spots along your fuel lines as close as you ca to the tanks up to the injector pump. On the suction side (before the injector pump) the source of air will usually, but not always, involve a fuel leak. It could be as simple as the rubber fuel line that goes from the frame over to the lift pump (the one on the side of the engine) or it could be as complicated as the tank selector valve (FSV). Even worse was the case of someone having a small rust hole on the top of one of his steel fuel lines that run along the frame. It didn't leak fuel, but would let all of the fuel drain back after he shut the engine off.
 

franklin2

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So you would recommend replacing all of the fuel line from the tank to the fuel filter/separator with A/N fittings and braided hose? Instead of putting a band aid on it?
There is nothing wrong with the stock system if it's maintained. I do not particularly like the quick disconnect o-ring fittings on the plastic lines, but I have had good success just getting rid of those fittings and using short pieces of fuel line and hose clamps.

It sounds like your problem is not going back to the tanks, but is on top of the engine. If you had air problems from the pump back to the tanks, that usually causes surging going down the road.

If it starts in the morning and then quickly stops, and then there is a lot of cranking, that is usually a sign you have a air leak on the fuel system on top of the engine. The most common places for this are the o-rings around the injectors that go to the little return lines, and any other places that are damp like the fuel heater on top of the fuel filter, and any other lines on top of the engine that have a fuel dampness around them.
 

IDIBRONCO

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There is nothing wrong with the stock system if it's maintained. I do not particularly like the quick disconnect o-ring fittings on the plastic lines, but I have had good success just getting rid of those fittings and using short pieces of fuel line and hose clamps.

It sounds like your problem is not going back to the tanks, but is on top of the engine. If you had air problems from the pump back to the tanks, that usually causes surging going down the road.

If it starts in the morning and then quickly stops, and then there is a lot of cranking, that is usually a sign you have a air leak on the fuel system on top of the engine. The most common places for this are the o-rings around the injectors that go to the little return lines, and any other places that are damp like the fuel heater on top of the fuel filter, and any other lines on top of the engine that have a fuel dampness around them.
Again checking for wet or dirty spots first before just replacing parts trying to fix the problem.
 

Clb

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Tldr
Ever
wonder
why
the Schrader valve is on the filter?
No you cannot attach LOW P.S.I. air to it and start soaping the lines down....
You have to come up with the oops part on yer own!
 
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