Bypassing fuel filter
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Bypassing fuel filter
Trying to finish up an engine install ('86 Bronco 5.0 efi), and ran into some fuel related problems. No fuel flow. No power to pump.
I haven't finished the diagnostics for that yet. But while checking the pump I noticed that the fuel return line snapped off of the canister mounted filter.
There is also an inline type fuel filter. Do I really need 2?
Is there any reason not to eliminate the canister fuel filter?
I haven't finished the diagnostics for that yet. But while checking the pump I noticed that the fuel return line snapped off of the canister mounted filter.
There is also an inline type fuel filter. Do I really need 2?
Is there any reason not to eliminate the canister fuel filter?
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From: Louisville,Ky.
Bypassing fuel filter
Canister filter? I know that there is one on the supply line, it is metal with an in and an out. It should be on the framerail somewhere. Where is the filter that broke located on the truck?
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Bypassing fuel filter
It's located on the frame rail, next to the transfer case, between the tank and the high preasure fuel pump.
Both supply and return fuel lines pass through it. The "canister" is plastic, and the "nozzle" that the fuel return line attaches to broke off.
The other filter is your standard inline filter, and is located on the supply line between the high preasure pump and the fuel rail.
Both supply and return fuel lines pass through it. The "canister" is plastic, and the "nozzle" that the fuel return line attaches to broke off.
The other filter is your standard inline filter, and is located on the supply line between the high preasure pump and the fuel rail.
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Joined: Dec 2001
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From: Louisville,Ky.
Bypassing fuel filter
I am not sure why you would filter the return, but I don't see bypassing it would hurt anything as long as it is filtered before the injectors. Just be sure that your bypass will withstand at least 50PSI just to be safe.
Jimmy
Jimmy
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Bypassing fuel filter
Thanks for the tip.
I'm guessing that both lines go through it as a design or assembly line convenience.
Unfortunately I haven't had time to work on it. Probably tomorrow...
I'll replace it if I can find one. But right now getting it to run is the priority. And bypassing will be easy and quick to accomplish. Sort of. If I wanted to hide something in an inaccessible location, I'd strap it to that canister.
Based upon the contents of the filter when I first changed it, I don't think the previous owner or his mechanic was aware of it's existance.
I'm guessing that both lines go through it as a design or assembly line convenience.
Unfortunately I haven't had time to work on it. Probably tomorrow...
I'll replace it if I can find one. But right now getting it to run is the priority. And bypassing will be easy and quick to accomplish. Sort of. If I wanted to hide something in an inaccessible location, I'd strap it to that canister.
Based upon the contents of the filter when I first changed it, I don't think the previous owner or his mechanic was aware of it's existance.
Hotshot
Joined: Oct 2002
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From: The Big, Oregon
Bypassing fuel filter
That is a pre-filter to help protect the high pressure pump. If that is broken, replace it. You probably can get one out of the junkyard, but replace the filter in it. Talk to Steve83 about the filter part number.
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Bypassing fuel filter
Finding the filter part is not a problem. But the canister may have to come frome a junkyard, which I'm trying to avoid, at least temporarily.
It's just the return line that is broken. Do you think capping the return lines on the canister would be a problem? and routing the return lines around the canister?
I'm devoting tomorrow morning to finishing up my diagnostic checks, and will removing the canister to verify that only the one line is damaged.
It's just the return line that is broken. Do you think capping the return lines on the canister would be a problem? and routing the return lines around the canister?
I'm devoting tomorrow morning to finishing up my diagnostic checks, and will removing the canister to verify that only the one line is damaged.
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From: Louisville,Ky.
Bypassing fuel filter
I would think that they are separated internally so that the fuel doesn't go straight back to the tank thru the return.
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Bypassing fuel filter
I finished my diagnostics: two loose wires were preventing the high preasure pump from working. (Well, at least one was, the other may be unrelated).
Back to the topic here, I removed and examined the canister. The piece that broke off was still connected to the fuel line. So, as a temp fix I superglued it in place, then liberally coated the outside of the affected 'tube' with epoxy.
Works well enough for now. I'll work on getting a replacement before the truck becomes street-certified.
The mechanics of the cannister are a little more complicated than I would have thought.
4 lines, Fuel-in, fuel-out, return-in, return-out.
Fuel-out seals up to the center of the filter.
Fuel-in goes to a valve that dumps fuel to the bowl.
Return-in and return-out are directly connected *and* T into a valve that dumps into the bowl.
So pre-filter fuel is obtained both from the tank and from the fuel return line.
Note: I didn't mean to imply that I was going to cap the return line, just the fitting for it on the canister. But with that latter feature I no longer think it's a good idea.
Back to the topic here, I removed and examined the canister. The piece that broke off was still connected to the fuel line. So, as a temp fix I superglued it in place, then liberally coated the outside of the affected 'tube' with epoxy.
Works well enough for now. I'll work on getting a replacement before the truck becomes street-certified.
The mechanics of the cannister are a little more complicated than I would have thought.
4 lines, Fuel-in, fuel-out, return-in, return-out.
Fuel-out seals up to the center of the filter.
Fuel-in goes to a valve that dumps fuel to the bowl.
Return-in and return-out are directly connected *and* T into a valve that dumps into the bowl.
So pre-filter fuel is obtained both from the tank and from the fuel return line.
Note: I didn't mean to imply that I was going to cap the return line, just the fitting for it on the canister. But with that latter feature I no longer think it's a good idea.
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