Few questions on fuel delivery

[84cucv1ton]

My 08 is starting run for a few minutes kicks down off my idle and shuts off. Started back up moving around some second I let off the gas stalls again. I replaced a few Hoses that were dry rotted. Seem to help but still happening.


Now my 09 is losing power. I mean no power goes to a point where the petals to the floor and him barely moving. Injection pump was rebuilt a few years ago. All new rubber fuel lines. After it shuts off it starts right back up seems to run good few minutes later the same thing happens again. Was thinking maybe something is blocking the pickup in the tank?

As always thanks for the help.

 

[DeeLoc13]

I'm having the same problem. Is there anyone out there that knows the solution.

 

[Recovry4x4]

Socks in the tank can be a problem.Speddmon went through this a couple of years back.

 

[DeeLoc13]

Mine was running great going to work and back home. Just yesterday I clocked out of work and jumped into my m1009 ,drove about a 100 yards and it shut of on me. Was able to turn it back on to drive it back to my parking lot and it shut off again. Now it won't start. I tested the fuel pump and it works so I'm guessing it the injector pump. Anyone have any answers?

 

[84cucv1ton]

OK ill check the houses again, fuel pump. thats tests good ill drop the tank thanks

 

[Barrman]

Check the return line check valve on the IP. Even though the pump was rebuilt "a few years ago" it still could be your problem.

 

[84cucv1ton]

really.. ok clogged up maybe? thanks ill take a look

 

[tequilaiam]

Do you have the original fuel filter?

I had a similar issue on mine: would start, idle a bit then die. I'd have to rebleed the filter to get it going again.

After replacing all the rubber lines and cleaning the check valve on the IP I was still having the issue. I found the culprit was the vacuum switch in the filter housing. It didn't drip but did allow a bit of air in when not pressurized. Gravity acting on fuel in line I guess.

Anyway, that small air bubble was getting trapped in the filter so the truck would start and run off the fuel already in the line and then die. BUT it was always OK after I opened the bleeder on the filter, cranked a bit, then closed the bleeder. After getting the air out the truck would start and run fine until I shut it down again.

Something to check if you've already made sure your fuel lines are OK.

edit: this thread may help
http://www.steelsoldiers.com/showthread.php?37862-Fuel-Pressure-Switch-and-Hard-Starting-CUCV

 

[84cucv1ton]

yes i have the model 80 on both trucks. looks like one is leaking and one is getting air in.

 

[GM72K10]

This will show the symptons you are having. Changed it and all is good.

 

[dependable]

Since accessing the top of fuel tank at sender to clean tank screen can be a lot of work, if you suspect the 'sock' may be clogged at the fuel uptake line in the tank, blow compressed air into fuel tank from line before fuel (lift) pump.

If fuel flow is improved, clean fuel tank and sock.

 

[84cucv1ton]

this is what came out of my fuel filter

 

[Keith_J]

Nasty. Dropping the tank is a lot of work but worth it. Corrosion may be an issue.

 

[trooper632]

Mine was acting the same way, but I changed the fuel filter and that's all it was, change filter again if you havent

 

[original]

Mine was acting the same way, but I changed the fuel filter and that's all it was, change filter again if you havent

Oh yeah, I've had filters that would only last a couple weeks before needing replaced again. +1 on the change again or bypass the filter with fuel hose and a standard lawn and garden fuel filter for testing. If you use the right size hose, you can just remove the filter and use the same in/out ports that the original filter uses.

 

[84cucv1ton]

new wix filter on the way

 

[84cucv1ton]

there is water in there, no idea how that happened

 

[original]

Time for some diesel 911! Hahaha Condensation builds up if you keep the tank low. I try to keep my tanks at least halfway full in the summer and 3/4 in the winter. Use some type of water remover additive and fill the tank on top of it. Don't toss the old filter if it wasn't very old. It could have just had water clogging it instead of debris. Just lay the filter where it can dry out. A day or two in the sun will remove that water from the filter. Is it running any better with the new filter?

 

[acesneights1]

That is alot of water for a small sample. Drop and clean the tank. Water will destroy the IP. I'd even run some 2 stroke oil in the fuel after you get it all cleaned out.
Whenever I have a suspected fuel problem I use a little rig I made up years ago which has proven very useful in diagnosing many many diesel fuel issues. I took an outboard motor fuel tank and mounted a small universal lift pump on i with an inline fuel filter. It has leads with alligator clips and a long length of effluent fuel line.
Whenever I suspect a fuel system problem. I disconnect and plug the line right at the IP. I hook up my temporary tank, bleed and run. If the truck runs great, I know my problem is in supply. If no difference then I start looking at the IP etc.
I didn't catch which truck that fuel sample came from but the symptom of the M1009 sounds like a bad lift pump.
CUCV's have a unique feature that their civilian counterparts don't. Inside the passenger side wheelweel on the outside of the frame is a tee block on the fuel supply line for testing fuel pressure although I generlly like to intercept right at the fitting for the IP, the testing tee on the frame can show a bad LP.

 

[stampy]

Biodiesel will clean the crap out of a tank too (ask me how I know) When it's been sitting for a while expect to go through filters. Many of us have changed our square filters for a spin off filter. That helps with wear and tear on your starter and batteries as you can prefill the filter with diesel before cranking it over. This makes start up after changing a pretty easy job. I also like the fact you can drain the filter out easier and if on the side of the road backflush with diesel enough to get you to a parts store or home (but it's better just to keep a spare in the truck and a quart of trans fluid to fill it with.