Engine/Transmission (1998.5 - 2002) The Monster won't start, what am I missing?

[David_VT]

Hello all,
It has been a long time since I have posted. The green monster is on light duty these days as it slowly looses the battle with rust. Nevertheless it has always started despite the daylight reaching further and further into the body.

So, I parked it for a few weeks in the cold this winter. I was not surprised it would not start right off on a bitter cold day.

I did the 911 treatment to the fuel and topped off the charge to the fairly new batteries.
The horn did heat up so I know the heaters are working.
No luck but I could see pressure changes from the lift pump when the filter dump valve was slightly open.

I eventually plugged in the truck block heater and tried again (always several times).
No luck despite a few weak coughs

Today I replaced the fuel filter. After replacing the filter I eventually reached the point of some strong rumbling while the starter is cranking but never more than perhaps a second or two after the starter is disengaged.

What am I missing in this pursuit? It is up into the 30's today and I really want to get the beast out of the yard before the snow closes in.

Any thoughts??

 

[JR]

You mentioned pressure changes so I assume your monitoring lift pump pressure? Since you changed fuel filters did you crack an injector line or two to bleed the air out of the system? If you've got fuel spitting out at the injector lines at the head it should start.

 

[David_VT]

Those fuel lines are looking tender near the valve cover. Should I take the risk of putting a wrench to them?
I was thinking air but really nervous about splitting a line. Are those as thin as brake lines?

You mentioned pressure changes so I assume your monitoring lift pump pressure? Since you changed fuel filters did you crack an injector line or two to bleed the air out of the system? If you've got fuel spitting out at the injector lines at the head it should start.

 

[JR]

They are pretty stout, if you've somehow introduced air into the fuel system you will need to crack a line(s) somewhere to push the air out while cranking. Maybe spray some PB Blaster or something similar and let them soak for a bit. Unless you have a ton of air in your system you can generally get away with cracking 2 or 3. Pick the best looking ones and start there, if your getting a lot of foamy fuel you have air in the lines and will need to continue cracking lines until the truck will start. If your that concerned about your lines I would just start with one, make sure your getting a good supply of fuel at that line while cranking. If you have little or no fuel there may be other problems.
Just remember, this is high pressure fuel at this point so be careful while cranking. Only turn the injector nut until its loose enough to be able to turn by hand

 

[David_VT]

Well, I pulled three codes that were set: 234,1698,1688
I cleared and then 1688 set as soon as I tried to start

 

[JR]

That could be a bad one. Are your batteries good and charged? Do you know what kind of lift pump pressure you have?

 

[David_VT]

We are working it and I can get it to run rough to about 325rpm and stay running for a good while.
No throttle response.
We cracked each line at the head and see fuel. More from some than others.

 

[David_VT]

Hmmm never noticed a double post here before, edited it...

 

[JR]

Fuel pressure? Need to find out if you don't know.

Did it start on its own or did you have to crack a few lines to bleed the air out?

 

[David_VT]

My friend nudged it a bit with ether and that pushed it over the edge to stay running the first time.

After that we would start it and it would come up to about 325rpm and hold there without needing any encouragement.
Next we cracked each fuel line looking to see if we were not feeding every cylinder. Each time a line would start to leak that would kill the engine. Each line did show fuel at the head in that manner.
I have a few lift pumps from cummins and a Vulcan kit. Hopefully I can find them as it has been years since I stopped indulging my middle age toy...
The pyro and fuel pressure gauges long ago lost to the road salt along with the espar.

Could this be a wiring issue rather than IP failure? Does the lack of throttle response fit the 1688 code.

So do I pull a VP44 with 27k miles from my spare 01 engine that has not run in maybe 8 to 10 years?
Naturally I will replace the lift pump if going through all that trouble...

Decisions decisions...

 

[JR]

Not sure what type of lift pump your running but if it has retired the VP could be struggling to pull through it...I would at a minimum invest in a mechanical fuel pressure gauge so you know what's happenning. Until you do that it's just a guess as to what the problem is. If you can verify healthy fuel pressure to the VP, the 1688 pretty well narrows it down for ya unfortunately.

 

[MLee]

Looks like you put the 911 in the fuel tank, is this what you did? do a new filter and fill the new filter with 911 directly so it goes into the engine to desolve any and all? ice. You may have a fuel jelling situation. Douse the tank with anti-jell and get it mixed good. Return line, is it OK? Just few ideas to try.