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Discussion Starter #1
Possible dumb question.

I've been concerned about my fuel pressure ever since I contaminated my fuel with some white label power service fuel additive that I was storing in a plastic container that it "ate". I plugged a filter when it happened and was seeing some erratic needle movement so I changed filters again 2 weeks ago. It had more plastic residue on the rail filter but the filter on the engine was normal in appearance. My fuel pressure gauge is under the hood since it's an analog gauge and I didn't buy the kit to allow placement in cab. I started it up this morning and notice it vibrates between 50 and 60 just like 2 weeks ago. After I changed filters a couple of weeks ago it pretty much stayed at 60 like normal. I had my tallest helper push the accelerator and under some load it stabilized at 60. Didn't have time today to disconnect and put it so I could see thru the windshield while driving. I'm gonna try that next week and probably pull the filter again. Any one else see a needle flutter at idle or any thoughts on this?

This bone head move continues to haunt me.:damnit:bang:bang
 

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Don't beat yourself up Weld, were here for you.

I have a sender/stepper motor gauge setup on mine, needle on my gauge is always rock steady or slow moving downword a few psi when accelerating hard.

Mine reads 72psi average, and cold mornings it will be 75-77psi which makes my 75psi red alarm light in the gauge light up, I have the alarm set for 45 psi low and 75psi high.

Worse case scenario sounds like the HFCM fuel pump may be weak if the fuel filter didn't fix it, or maybe the HFCM inlet line going to the fuel tank is clogged?

Your truck dosen't have a steel fuel tank by any chance does it?

Some trucks with steel fuel tanks had inner tank liner delamination issues that would cause similar symptoms like yours.

Harry
 
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Discussion Starter #4
Don't beat yourself up Weld, were here for you.

I have a sender/stepper motor gauge setup on mine, needle on my gauge is always rock steady or slow moving downword a few psi when accelerating hard.

Mine reads 72psi average, and cold mornings it will be 75-77psi which makes my 75psi red alarm light in the gauge light up, I have the alarm set for 45 psi low and 75psi high.

Worse case scenario sounds like the HFCM fuel pump may be weak if the fuel filter didn't fix it, or maybe the HFCM inlet line going to the fuel tank is clogged?

Your truck dosen't have a steel fuel tank by any chance does it?

Some trucks with steel fuel tanks had inner tank liner delamination issues that would cause similar symptoms like yours.

Harry
I'll check the tank I can't say for sure. The pick up tube suggestion was a thought too. I'm gonna pull the filter again and start looking at a replacement fuel pump and possibly pulling the fuel tank. Last thing I want to do is starting killing injectors with low fuel pressure.

Thanks for the moral support Harry!
 
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Mine will tick a pound or 2 but I just attribute it to a sticky relief valve in the regulator and stays around 60 psi.
Does your regulator have the blue spring upgrade?

I've always wondered why mine reads so high after installing the complete Ford oem blue spring upgrade kit that uses a new cover and internals. Another guy I know with an 03' say's his reads like mine too with the Ford kit.

45-75psi is the spec, 45 being bare minimum and 75 being max. But mines been like this for years now with no issues yet. Just concerns me a little during cold weather season and the fuel starts to thicken, the pressure is a bit on the high side until the fuel warms up and thins back down.

Harry
 

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Does your regulator have the blue spring upgrade?

I've always wondered why mine reads so high after installing the complete Ford oem blue spring upgrade kit that uses a new cover and internals. Another guy I know with an 03' say's his reads like mine too with the Ford kit.

45-75psi is the spec, 45 being bare minimum and 75 being max. But mines been like this for years now with no issues yet. Just concerns me a little during cold weather season and the fuel starts to thicken, the pressure is a bit on the high side until the fuel warms up and thins back down.

Harry
Yes, it has the blue spring. Pressure was 50 psi with the stock spring.

Weld, when I harpooned my tank I found the pickup screen rotted off the the bottom and laying in the tank. Just something to look for if you drop the tank.
 

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Discussion Starter #8
I have a hunch my screen is plugged up.

Is the screen replaceable or will I need a hole new sending unit?

Looks like I better get the tank dropped soon.

I would typically see 60 psi just like jsm180 w/ blue spring. I never had a pressure gauge before I did the upgrade.
 

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The screen is replaceable, just pushes on. My local dealer hit me for $70, I think Tousley had it for $40, I couldn"t wait.
Found the screen on eBay for $34 with free shipping. I hope to pull it Saturday, my recent repair work on my knee has slowed me down a bit. Nothing like an ACL replacement to make things interesting right now. I'll take pics when I get it apart but I'm pretty sure it's plugged. It looks like there is a bypass on the side so if that's the case that may be causing the needle fluctuations at idle opening and closing? I'll put a magnet to it tomorrow night and see if tank is steel. Just been busy with work.

Any tips on dropping the fuel tank? It's a crew cab short box 4x4. Some fuel line connection tools look like a must have. Calling for snow flurries on Halloween. :roflol:
 

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Found the screen on eBay for $34 with free shipping. I hope to pull it Saturday, my recent repair work on my knee has slowed me down a bit. Nothing like an ACL replacement to make things interesting right now. I'll take pics when I get it apart but I'm pretty sure it's plugged. It looks like there is a bypass on the side so if that's the case that may be causing the needle fluctuations at idle opening and closing? I'll put a magnet to it tomorrow night and see if tank is steel. Just been busy with work.

Any tips on dropping the fuel tank? It's a crew cab short box 4x4. Some fuel line connection tools look like a must have. Calling for snow flurries on Halloween. :roflol:
It's pretty straight forward, drain as much fuel as you can, I didn"t raise the truck but with a stiff knee it might be easier. I used 2 ratchet straps between the frame rails to raise and lower the tank, a floor jack or 2 would work also. My tank was plastic.
 

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With a bad knee it would be easier to raise the bed if the bed bolts are not too rusted. You have to replace them, one time use.

As js180 stated, two to four straps is good along with a floor jack.

Remove skid plate if in place.

Disconnect the two hoses at the filler door. They will be stuck to the filler assembly nipples.

Snug up straps.

Remove the bolts for the retaining straps by the driveshaft. At floor height, you may want to just remove them altogether.

Work the tank down a few inches with the straps/jack; you'll be pushing the fill/vent tubes to the filler between the frame rail and bed a few times.

The next part you have to reach over the frame or over the tank from the driveshaft.

Use the spring line connector tools to release the two flexible lines.
Remove the front and rear balance vent hoses. They go to a hard line on the rail and IMO it's just easier to replace that with one rubber hose laying on the tank between the balance vent nipples when it's going back up.

Disconnect the electric.

Lower tank using the straps the rest of the way.

The large nut on top of the tank that retains the float/pickup assembly can be a pita. I've used a flat bar and hammer to "impact" it off carefully. Some people including me have had good luck warming the cap before install to make it go back on easier. I also put some motor oil on the threads to help installation.

Carefully remove the assembly out of the tank as you do not want to bend the float lever.

Then just reverse.

I used to have a pictorial for this but it went away with Webshots.
 
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With a bad knee it would be easier to raise the bed if the bed bolts are not too rusted. You have to replace them, one time use.

As js180 stated, two to four straps is good along with a floor jack.

Remove skid plate if in place.

Disconnect the two hoses at the filler door. They will be stuck to the filler assembly nipples.

Snug up straps.

Remove the bolts for the retaining straps by the driveshaft. At floor height, you may want to just remove them altogether.

Work the tank down a few inches with the straps/jack; you'll be pushing the fill/vent tubes to the filler between the frame rail and bed a few times.

The next part you have to reach over the frame or over the tank from the driveshaft.

Use the spring line connector tools to release the two flexible lines.
Remove the front and rear balance vent hoses. They go to a hard line on the rail and IMO it's just easier to replace that with one rubber hose laying on the tank between the balance vent nipples when it's going back up.

Disconnect the electric.

Lower tank using the straps the rest of the way.

The large nut on top of the tank that retains the float/pickup assembly can be a pita. I've used a flat bar and hammer to "impact" it off carefully. Some people including me have had good luck warming the cap before install to make it go back on easier. I also put some motor oil on the threads to help installation.

Carefully remove the assembly out of the tank as you do not want to bend the float lever.

Then just reverse.

I used to have a pictorial for this but it went away with Webshots.

Wow that's great info. I wish you still had those pics. As they say, a pic is worth a thousand words.
 

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Discussion Starter #15
Confirmed tank is plastic tonight. Gonna tear into it Saturday. Thanks for the tips. I've got about 15 gallons of fuel to siphon out too.
 

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Now that I'm home and not in the middle of a field planting Christmas tree seedlings .... Nope no pictures even in my old Jaz backup.

However, all is not lost as the manual is pretty good.

View attachment Service Manual.pdf

View attachment Sender.pdf

I've taken the tank down with it being 1/2 full. Not fun but it can be done. It just gets wonky as the fuel ships end to end.
 

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I pray you find an issue in the tank once it's apart Weld. Nothing better than catching a confirmed suspect during a repair.

Harry
 

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Discussion Starter #19
Of all the possible problems with a 6.0 this has never been an issue for me. :roflol:

The pics do have me seriously thinking about lifting the bed though.

I think it may save me from a severe scolding by my wife.

Thanks!
 

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Just remember my first line in a post above: ....if the bolts are not too rusted.

Those are self threading bolts into frame mounted clip nuts. With new vehicles they were fine to remove. As the threads and the clips get rusted they become PITA and well, you've got a Michigan truck. On older vehicles we sometimes broke the torx drivers or had the clips break off from rust erosion (free spinning). Then we had to drill them to get the head off or use an angle grinder to remove the head. Once we had the bed off then we usually ground the clip and let the bolt drop through. If the clips break with most you can have someone hold the nut with a wrench while you're impacting them from above, but if I remember correctly there are one or two you can only access by dropping the tank. And then you're back to what you were trying to avoid.

If all depends on the rust factor. Dealers usually have the bolts and nuts in stock.
 
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