Anyone have a pic of the inside top of a 6.2 injection pump?

[Mogman]

.. after over 50 miles it started acting up again.

Started up fine, idled for 15 minutes to warm up.. got about four blocks down the road and got chuggy then died. Cranked like it was outta fuel, I stomped on the pedal a few times and it restarted, got about a block and it happened again. Repeated this process till I made it home. I pulled the fuel return check valve out and drilled it out so it’s open all the time just in case it was that front solenoid that was giving me issues.. same situation.

Looks like a new (rebuilt) pump is in my future.

That does not sound like a typical IP issue, more like a plugged return or fuel starvation.(although I am not always right!)
Did you pop the fuel cap off to see if it had built a vacuum?

 

[Humpty]

That does not sound like a typical IP issue, more like a plugged return or fuel starvation.(although I am not always right!)
Did you pop the fuel cap off to see if it had built a vacuum?

Yeah, I took the fuel cap off... still did it with the fuel cap off.

I'm going to pick up a fuel pressure gauge from Harbor Freight tomorrow.. i wonder if I can hook the gauge up with a T to monitor the pressure while the truck is running.

I ran it today and immediately after it died I popped the fuel line off the filter and fuel blasted out so there was for sure pressure in the line from the IP to the fuel filter. I opened the top of the IP and it was full of fuel.. I removed the fuel return line from the top of the IP and cranked it over and it flooded the valley with diesel fuel as it shot out of the top of the IP so it's for sure getting fuel to the pump... maybe it's not getting enough pressure? The mechanical lift pump is 100% squirting fuel with every rotation of the engine.

I read in one quasi related thread that there should be about 6psi out of the filter to the IP. I planned on checking that tomorrow to rule out a fuel delivery issue before I ordered the rebuilt pump on Monday.

 

[swbradley1]

Seafoam.. lot of guys swear by the gallon jugs of Lucas Oil.. i’m told even Stanadyne themselves market a fuel additive for $10 that treats 60 gallons.

I’ve heard old timers talk about ATF for years in the crankcase. Get a burn? Rub ATF on it. Lose a finger? Throw it in ATF fluid and try to get to the hospital within 3 days. This is the first time i’ve ever put it anywhere but the transmission. lol Seems to be purring right along tho.

We have used ATF to break bolts/nuts free. Make 50/50 mix of ATF and Acetone. Works better than any of the commercial stuff I've used.

Next time I cut a digit off I'll try the ATF, it's only 15 minutes to the hospital.

 

[Milcommoguy]

Yeah, I took the fuel cap off... still did it with the fuel cap off.

I'm going to pick up a fuel pressure gauge from Harbor Freight tomorrow.. i wonder if I can hook the gauge up with a T to monitor the pressure while the truck is running.

I ran it today and immediately after it died I popped the fuel line off the filter and fuel blasted out so there was for sure pressure in the line from the IP to the fuel filter. I opened the top of the IP and it was full of fuel.. I removed the fuel return line from the top of the IP and cranked it over and it flooded the valley with diesel fuel as it shot out of the top of the IP so it's for sure getting fuel to the pump... maybe it's not getting enough pressure? The mechanical lift pump is 100% squirting fuel with every rotation of the engine.

I read in one quasi related thread that there should be about 6psi out of the filter to the IP. I planned on checking that tomorrow to rule out a fuel delivery issue before I ordered the rebuilt pump on Monday.

My guess is the metering valve is all gummed up or sticking rusted advance lever and seals. Pumps are precision like a fine watch working at + 2000 psi injection pressures. Supply pressures of 3 - 7 psi OK. Lift pump should be able to fill 16 oz water bottle in 3 or 4.... 20 second cranking cycles at the output of filter to IP Pump. (yea, drain line works, but what's really going on)

Check and a deep clean with some solvents, might clear it up, might.

I point one to the easily read free overview for most of the questions that show up here. Section 3 for fuel.

https://gear-report.com/wp-content/uploads/2017/03/HMMWV%20A1%20Troubleshooting.pdf

Another guess, twenty plus year old pump, truck parked for 10, nasty fuel, only 180 miles on the clock (clue to send one down the rabbit hole)

Might start looking for a new pump too, Thank You, Camo

 

[TNDRIVER]

Yeah, I took the fuel cap off... still did it with the fuel cap off.

I'm going to pick up a fuel pressure gauge from Harbor Freight tomorrow.. i wonder if I can hook the gauge up with a T to monitor the pressure while the truck is running.

I ran it today and immediately after it died I popped the fuel line off the filter and fuel blasted out so there was for sure pressure in the line from the IP to the fuel filter. I opened the top of the IP and it was full of fuel.. I removed the fuel return line from the top of the IP and cranked it over and it flooded the valley with diesel fuel as it shot out of the top of the IP so it's for sure getting fuel to the pump... maybe it's not getting enough pressure? The mechanical lift pump is 100% squirting fuel with every rotation of the engine.

I read in one quasi related thread that there should be about 6psi out of the filter to the IP. I planned on checking that tomorrow to rule out a fuel delivery issue before I ordered the rebuilt pump on Monday.

I think its time to put an eyeball inside the fuel tank. Myself and others have found nasty stuff in them. My two cents.

 

[Milcommoguy]

I think its time to put an eyeball inside the fuel tank. Myself and others have found nasty stuff in them. My two cents.

EYEBALL view of one kind of gunk in the fuel tank picture. This stuff was like very cold honey. Super sticky. That was a new tank two years ago. Want ta see more?

A total fuel system mess throughout, CAMO

.....

 

[Guyfang]

Might want to look at buying your fuel someplace else.

 

[TNDRIVER]

EYEBALL view of one kind of gunk in the fuel tank picture. This stuff was like very cold honey. Super sticky. That was a new tank two years ago. Want ta see more?

A total fuel system mess throughout, CAMO

View attachment 942435 .....View attachment 942436View attachment 942437

Don't want to see any more, too much experience r and r'ing fuel tanks already. I believe there is a picture of a guys 1114 tank on here that is incredible.

 

[Mogman]

I would work with it quite a bit more before removing the IP, if it runs at any time correctly then at most you have something "sticking"
Question at any time did you have a very filthy fuel filter? If so there is a screen in the fuel input fitting to the IP that could be plugged, it has happened before but usually only on a filthy fuel system that had forced crap past the filter or an incorrectly installed filter.
Also have you determined that the fuel return line is not plugged?, you can run a line from the IP fuel return fitting into a bucket to test.
Also do a video of it ruining and dying might be helpful.

 

[Mogman]

Yeah, I took the fuel cap off... still did it with the fuel cap off.

I'm going to pick up a fuel pressure gauge from Harbor Freight tomorrow.. i wonder if I can hook the gauge up with a T to monitor the pressure while the truck is running.

I ran it today and immediately after it died I popped the fuel line off the filter and fuel blasted out so there was for sure pressure in the line from the IP to the fuel filter. I opened the top of the IP and it was full of fuel.. I removed the fuel return line from the top of the IP and cranked it over and it flooded the valley with diesel fuel as it shot out of the top of the IP so it's for sure getting fuel to the pump... maybe it's not getting enough pressure? The mechanical lift pump is 100% squirting fuel with every rotation of the engine.

I read in one quasi related thread that there should be about 6psi out of the filter to the IP. I planned on checking that tomorrow to rule out a fuel delivery issue before I ordered the rebuilt pump on Monday.

You should be able to connect the fuel pressure gauge to the water drain line and open the valve.

 

[Guyfang]

I once spent weeks chasing a problem like this. It was a small piece of plastic in the fuel tank. Every now and then it floated over by the pickup tube. Get sucked up. Stop the flow to the IP. The engine stopped. The plastic would drop off the pickup tube, and float away. Only to be picked up again later on. I know its probably a PITA to pull the tank, and clean it. But if you can get at least a gander in the tank, you might see something.

 

[Humpty]

You should be able to connect the fuel pressure gauge to the water drain line and open the valve.

I cobbled together a brass T and put the fuel pressure gauge in the line going from the filter to the IP.. it ran with a straight shot to the IP with the pressure gauge on the T but not great and only showed about 1 pound of pressure. With the gauge on the T it wouldn’t start.

With nothing but the gauge on the filter it cranks up to just under 5 pounds of pressure just cranking it over.

Are you saying put a T on the water drain line?

 

[Humpty]

I would work with it quite a bit more before removing the IP, if it runs at any time correctly then at most you have something "sticking"
Question at any time did you have a very filthy fuel filter? If so there is a screen in the fuel input fitting to the IP that could be plugged, it has happened before but usually only on a filthy fuel system that had forced crap past the filter or an incorrectly installed filter.
Also have you determined that the fuel return line is not plugged?, you can run a line from the IP fuel return fitting into a bucket to test.
Also do a video of it ruining and dying might be helpful.

I pulled the fuel return line valve out and drilled it out. It is permanently wide open because I thought maybe the solenoid may not have been opening it.

When I replaced the fuel filter it didn’t look bad at all. I just did it because the truck was new to me and thats just one of the things you do.

There is for sure plenty of fuel getting to the IP.. cranking it over with the return line off fills up the valley pretty quickly with fuel.

My Harbor Freight pressure gauge connected directly to the output of the fuel filter hops up to 4.5 pounds.

To post a video I must have to upload it somewhere else, it looks like it only allows still photo attachments.

 

[Humpty]

Here's a video of how it sounds when it acts up.. sometimes it'll do this and then just be fine again... other times the "rurrr... rurrrr.... rurrrrr" will get longer and longer and then it'll die.. then it'll run fine for 200 miles.

http://www.diyhmmwv.com/IMG_6967.mov

 

[Mogman]

You still have not said if you have confirmed the fuel return LINE is not plugged.
For some reason I cannot see the vid.

 

[Mogman]

I pulled the fuel return line valve out and drilled it out. It is permanently wide open because I thought maybe the solenoid may not have been opening it.

When I replaced the fuel filter it didn’t look bad at all. I just did it because the truck was new to me and thats just one of the things you do.

There is for sure plenty of fuel getting to the IP.. cranking it over with the return line off fills up the valley pretty quickly with fuel.

My Harbor Freight pressure gauge connected directly to the output of the fuel filter hops up to 4.5 pounds.

To post a video I must have to upload it somewhere else, it looks like it only allows still photo attachments.

The cold advance solenoid does not "open" the return check valve.