Fuel pump issue -- can't get fuel rod back in block

[Mogman]

DieselHub.com??
You have not said if you have removed the check valves, also you have replaced the fuel filter on the firewall yes?
From what you have said so far I would not suspect the IP yet...

 

[Action]

Plugged vent lines could lead to a vacuum in the tank. Check the little can behind the coolant overflow tank, and see if the end is clogged up. Maybe by mud dobber.

Did you leave the old pushrod in the block behind that plate?

Following the steps in the TM will take you step by step through troubleshooting.
With fuel cutoff solenoid wire disconnected from IP to prevent starting during test, you should get 1/2 pint of fuel from water drain. From 30 seconds of cranking. That would check everything downstream of that point, including tank, lines, 2 one-way input valves, and lift pump.
Do not crank for the full 30 seconds in one shot.

 

[TNDRIVER]

Yep we dropped the tank last year to troubleshoot the sender and the tank was surprisingly clean. Tank sock looked pretty clean too but I regret not doing a closer inspection considering the current situation.
Planning to check to the fuel injector next. Any and all suggestions appreciated, thanks for your time and help!

View attachment 869107

I think you will be surprised at how fast algae will grow in diesel fuel in these trucks. Over the course of my career I've purchased close to 3/4 of a million gallons of diesel and never had a bio problem until the HMMWV's came along. I dose every tank with POWER GUARD. Let us know what you find please.

 

[M998 NYC]

Plugged vent lines could lead to a vacuum in the tank. Check the little can behind the coolant overflow tank, and see if the end is clogged up. Maybe by mud dobber.

Did you leave the old pushrod in the block behind that plate?

Following the steps in the TM will take you step by step through troubleshooting.
With fuel cutoff solenoid wire disconnected from IP to prevent starting during test, you should get 1/2 pint of fuel from water drain. From 30 seconds of cranking. That would check everything downstream of that point, including tank, lines, 2 one-way input valves, and lift pump.
Do not crank for the full 30 seconds in one shot.

Thanksfully no IP or injector issues, or really the need to even explore -- the new OEM mechanical pump is back in and truck is running strong. Much appreciated on these bits of advice and yes, the TM is my first line of defense...

 

[M998 NYC]

DieselHub.com??
You have not said if you have removed the check valves, also you have replaced the fuel filter on the firewall yes?
From what you have said so far I would not suspect the IP yet...

Missed that, my bad. Yes to check valves and fuel filter. Better yet, the new OEM pump installed smoothly (after stupidly trying to get the rod in with plate on). Truck is running great. Thanks for chiming in on my behalf

 

[M998 NYC]

Plugged vent lines could lead to a vacuum in the tank. Check the little can behind the coolant overflow tank, and see if the end is clogged up. Maybe by mud dobber.

Did you leave the old pushrod in the block behind that plate?

Following the steps in the TM will take you step by step through troubleshooting.
With fuel cutoff solenoid wire disconnected from IP to prevent starting during test, you should get 1/2 pint of fuel from water drain. From 30 seconds of cranking. That would check everything downstream of that point, including tank, lines, 2 one-way input valves, and lift pump.
Do not crank for the full 30 seconds in one shot.

Nice idea to test. Lucky new mechanical pump installed without issue and trucks running strong! Still unsure as to why the previous two electrical pumps crapped out, either way I'm glad I have it back to the mechanical system as intended. No need to have unnecessary draw on the batteries too. Thanks for your help!

 

[M998 NYC]

I think you will be surprised at how fast algae will grow in diesel fuel in these trucks. Over the course of my career I've purchased close to 3/4 of a million gallons of diesel and never had a bio problem until the HMMWV's came along. I dose every tank with POWER GUARD. Let us know what you find please.

All good, the new pump installed smoothly and truck is back in action. Good know on the algae. As far as you know does this typically only happen in warmer climates? Would this be a concern if I'm refilling about once or twice every other month?

 

[Coug]

warmer climates can increase growth, but all you really need is water and light for algae to grow in diesel.

Going through the tank of fuel at least once per month, you really shouldn't be seeing any issues. It's typically longer term storage, but if the fuel is contaminated then it doesn't take very long.

 

[TNDRIVER]

All good, the new pump installed smoothly and truck is back in action. Good know on the algae. As far as you know does this typically only happen in warmer climates? Would this be a concern if I'm refilling about once or twice every other month?

I have a suspicion the algae growth has something to do with translucent nature of the tanks themselves. The fuel treatment has instructions for "shock treating" the fuel. This will kill the algae "in place" but leaves something akin to coffee grounds when it kills it. Once growing (slimy blobs) it will not pass thru a fuel pickup sock in the tank but all it needs to reach the filter is a minute piece to set up camp on the filter itself where it begins to grow there. The bottom of the fuel filter housing has the sump for water to accumulate and is difficult to clean on the truck. The amounts of treatment needed are very small for a 25 gallon tank. I drag out the calculator and mix the stuff into 5 gallon of fuel so that about a quart is added to my 15 or so gallon fill ups to keep it treated. Which reminds me I need to check and see if my second mortgage approval came through, I need to top off a tank. Good luck with your truck, enjoy.












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[Mogman]

Actually "diesel Algae" is not algae at all it is actually bacteria and therefor does not need light to grow, otherwise only transparent fuel tanks would be susceptible.
If you do not have algae don't keep yourself up at night worrying about it.
I live in a supposedly ideal environment for "diesel algae" it is very hot and humid most of the time here, I routinely let equipment sit for many years and have only had one instance of bacteria in one load of bulk diesel in over 30 years, it was immediately recognized because it plugged the secondary filter on the pump being too fine to be caught in the primary filter.
I treated the tank and all machines that had received the diesel one time and changed all the filters on an accelerated schedule for a while and that was about 10 years ago.
The bacteria does require water to survive, keep the water out and you will go a long way to preventing "diesel algae"
If you have the bacteria your fuel will have a milky or hazy look to it.