One to hang on the wall

[Truck Shop]

A DDEC III with waxed fuel, got some 911 and treatment in it and got it in the shop just barely
before it died. So let it set in side over night, checked the fuel this morning and could see the bottom
of fuel tank-cleared up. Went to start it, no go. Tack moved fuses were good, would try to on a wiff
of ether. Checked filters {ok} decided to check fuel supply pump mounted at back of compressor.
checked to make sure compressor was turning {ok}. I pulled the out line no fuel on crank over.
Had a derelict setting out in the yard so removed that pump and installed, fired right up after a few
revolutions. In my years I have never seen one take a dump like that, that quick. Don't if it was just
age plus the waxed fuel that stopped it's clock.

Anyone ever see one of those pumps just up and quit in cold conditions?

 

[Truck Shop]

Apparently no one has because in 9 hrs since posted zero reply. So that makes it a odd one, a first
for me and everyone on here. Hang it on the wall.

 

[JPV]

Is it just a gear pump like the Cats use, running about 75 to 95 psi or something more exotic?

 

[Truck Shop]

Is it just a gear pump like the Cats use, running about 75 to 95 psi or something more exotic?

Just a transfer pump, out fuel goes into a secondary filter. Not high psi. I even called a old Detroit service
mgr that had years working the floor--he had never heard of or seen one quit instantly like that. There is
a built in pressure relief-I pulled it apart and found nothing. It can develop a low pressure issue and cause
low power but not just give up the ghost. Gear on gear pump.

 

[JPV]

That's definitely one to hang on the wall, guess they have to die somewhere but c'mon, SITTING IN THE SHOP? My public school math can't begin to calculate the odds...

 

[Tyler d4c]

Perhaps the gear came lose on the shaft due to chunky fuel and warming up made it totally let go

 

[Coaldust]

I’ve had weird crap happen after a freeze up like that. Bad primer pumps, injector problems, fuel leaks that suddenly appeared. Never a transfer pump. Leaves you wondering why it was even running beforehand.

 

[kshansen]

Strange for a basic gear pump to just up and fail!. First thing I thought was the relief valve but then saw you checked that already. Could there have been some piece of crap holding the valve open and it fell out un-noticed while removing the pump? Only thing else I could imagine is if the driven gear was loose on the shaft and slipping under pressure, but that would be obvious if you had pump apart.

We used to use old 71 series fuel pumps to pump solvent in shop built parts washing tanks and they would run for many years pumping unfiltered solvent without failing. Hard to imagine one of them failing pumping filtered fuel oil.

 

[Truck Shop]

It happened with the tow truck, Jeff ran it down to a card lock to fuel it the day before right after I made
a 378 mile trip with it, obviously that vendor had cut his fuel enough. It ran fine, has been running fine.
Didn't take long to find the issue and fix it, 1 hour. But still the fact it's very strange.

 

[mks]

First real diesel experience.
1994 series 60 crank no start.
Thought it maybe that pump. A good friend with experience said not likely and it won’t go with the check, stop engine lights not coming on.
Got the air purged and was looking the blue print schematic over and believe I found a related circuit that was not powered on and began a physical search for its ends. My son found a switch near drivers side dash hanging out of the way and flipped it. Dash lit up and so did the engine.
Thank you all for sharing your knowledge!