Did some searching. Still need help. Fuel related

[myko2012]

My m1009 lost power with throttle input and would die if I gave too much pedal. I had to feather to bring RPMs up.

This is vehicle is very new to me. I drove it for about 5 hrs trying to make the trip home from PA to TN.

its a 1985 with 44k miles on it. It started losing power progressively going up the slight grades on the freeway. I pulled off the freeway to grab a bite and it died going up the ramp.

Anyways. Towed home. Started and pulled into my driveway and it's been sitting since. I replaced the fuel filter and added additives. When I bled the filter, the fuel came out bright and clean. It would start relatively easily but idled rough from that point. I figured I'd let it get up to temp and see how it would drive. The truck shut down while idling and hasn't started up since.

Things I have done. Replaced lift pump with AC Delco. Cleaned the return line check valve, busted out the glass ball in check valve, installed new check valve (neither made a difference.) added spin on filter (filled with diesel before cranking.) dog head relay.

The truck cranks but no start. There is some white haze that comes out both tail pipes when I crank. There is fuel in the hose after the check valve. Fuel pours out if I crack the filter open.

I'm thinking maybe the fuel tank sock could be loaded with gunk, I've got a new tank and pickup on order. I'd check the tank but I'm having a hard time removing the skid plate. The pintle hitch is in the way. Got two rusted bolts to deal with.

I did notice some seepage around the seam of the LP before I replaced it. That was the only identifiable wet spot on the truck.

I also have on hand an electric fuel pump. I was thinking about installing it inline with the mechanical LP. I have the necessary block off plate.

Thoughts on installing it inline to work with mechanical LP? If I bypass the mech LP, what do I do with the two lines that go into the mech LP?

Any other suggestions? Any more info needed? I've had the truck for two weeks and haven't driven it since the initial drive home. It was only 5 hrs but it was great.

 

[Mainsail]

The truck cranks but no start. There is some white haze that comes out both tail pipes when I crank. There is fuel in the hose after the check valve. Fuel pours out if I crack the filter open.

It sounds to me like you're getting diesel to the cylinders.

Are the glow plugs working?

 

[cpf240]

You say you cleaned the check valve on the IP. Was it dirty? A lot, a little? Just about anything stuck in that check valve is an indication that the IP needs to be rebuilt either now, or very soon. I'd suggest pulling the top cover on the IP and see if there is debris in there. These IPs are known for a ring in there that disintegrates over time.

If you suspect the fuel tank sock, you can disconnect the fuel line and run the hose into a clean jerry can of diesel. If the problem goes away, then you'll know there is some restriction in the supply line.

 

[myko2012]

I haven't verified the GP's since I brought the truck home. I know that the truck started no problems in the Pittsburg cold when I picked it up.

As for the IP check valve, yes it the ball was covered in crud.

As for the IP cover, I cracked open the cover and I've attached two pics, one of the inside of the cover, and one looking down into the IP. Thoughts?

 

[Skinny]

Just going off symptoms, I vote for IP replacement unless you are getting air in from old hoses.

At no point should adding or substituting an electric fuel pump solve any problems. The system works fine with a mechanical lift pump. The only reason to replace it with an electric is going to a turbo (to free up that port for oil return), you want an easier solution to priming the system after filter changes, or would like some sort of security system. Other than that, you are band aiding the problem with the electric pump.

 

[myko2012]

I definitely agree with band-aid fixing, Skinny. Never planned the electric pump as a fix. Just wanted to know how things are running with functioning mech LP vs strictly electric- also how the lines that once went to the mech LP are routed.

I will replace the IP, I want this thing as a dependable daily driver. My HMMWV in 2006 was a dependable beast in Afghanistan, and I want this thing just as reliable.

I've been doing some IP searches on Oregon Injection, but can anyone recommend THE IP the get? I am NOT doing any modifications to power output

 

[Warthog]

Looking inside the IP you can see the black specs. That is the governor ring coming apart. While it isn't the worst I have seen the end is near for the pump.

Make sure your GPs are working correctly. The 6.2L needs the extra heat to start.

 

[beltfedonly]

Try blowing some air into the fuel line at the lift pump back into the tank, with the fuel cap removed. If it runs better it is probably the sock in the tank clocked.

 

[beltfedonly]

I was trying to say the sock is clogged!

 

[myko2012]

Well I checked the GPs for resistance...all read less than 0.1 ohm

checked for voltage to the IP...

that's literally all I did and the truck fired right up. Idles and runs strong.

 

[Warthog]

The plugs should read 1-3 ohms each.

 

[Skinny]

I could understand the GP's causing problems on a cold start or even a fairly cool restart. What I don't buy is them being a culprit on a warm engine. One, the GP controller won't turn them on so that eliminates one problem. Two, even if the GP controller did turn them on, the affect would be negligible. A cool engine will restart without GP's without too many problems. Sure it may have extended crank times or a rough idle causing it to require a little throttle feathering. Unless it is really cold, the GP's won't be the long term problem.

One possibilty is is all the GP's are shorted and dropping your system voltage low enough to shut the IP solenoid down but highly unlikely IMO.

 

[myko2012]

I'm getting 12v to the IP. I've started many times now with no issues. Driven it around without any issues either.