Archived Truck dead on road.

[rluft]

I was pulling a 26 foot Krause disk at low speed (30mph for 100 miles). I topped a hill and the truck died as it idled down the hill (4 miles from home). I tried to restart while coasting in neutral and the engine will crank but not start. I got towed home and now need to get her running again. It seems that the engine shakes hard when turning over, more than when I have changed the fuel filter and had trouble starting. I added fuel to the tank in case the fuel gauge was inaccurate but it made no difference. I removed the BulleyDog box which didn't make any difference. Fuel pressure looks good. Looking forward to some suggestions prior to calling the dealer on Monday.

 

[MYeary]

Did you check for any codes, could be a sensor gone bad (crank or cam)

 

[rluft]

First thing I checked. No codes found.

 

[Missouri Mule]

Where did you take your fuel pressure test?



Do you think you should change fuel filter? Is fuel getting thru?



If VP44 is getting fuel I would try cracking (bleed) open one injector at time to see if that will fire the engine up (sometimes you have to open two or three at time).



Bleeding: loosen injector line a little when you see fuel come out tighten back up while cranking engine.



You weren't lugging engine?

 

[rluft]

Fuel pressure is taken at the injection pump, after the filter. The filter may need changed, I'll have to get one in town. The fuel pressure shows 16lbs at the IP so I would assume fuel is getting that far. I will crack a fuel line to see if fuel is getting to the injectors.

I was pulling with the overdrive off. I don't think that the turbo pressure ever exceeded 15lbs. When it stopped I was pulling on level road and the hilldropped away so the engine coasted and quit. Generraly, at 35 mph and the converter locked the motor was running about 1100 rpm. It may have lugged on some steep hills I encountered until the converter unlocked. Is that a concern?

 

[JFaughn]

You said you cracked an injector line , but did not say if you had fuel at the injector ?
With limited info , sounds like you have fuel , I would start thinking about maybe crank sensor , wiring ect , maybe the computer does not see the eng turning .
I do not remember which yrs , but I thought that some yrs you could not get codes with the key method & some yrs not all codes , then there is the issue that the computer dose not always get whats going on .
The trans/lock up is an issue if your trans temp tells you its get hot , at 1100 RPM you can be lugging eng/trans but your gages tell you if its too much .

 

[wtfd6]

he said he will crack the lines. let us know if you get fuel or not. does the tach work when cranking? if it does that rules out the crank sensor. actually I cant remember if the 01 uses the cam or the crank. I think in 01 they got rid of the crank sensor. I had an issue with mine.

 

[rluft]

Thanks. I will work on it after dinner this afternoon. I don't know if the tach is working and will check that. I don't know where the crank sensor is located, can someone help? Any other sensors I might check? I did change batteries a month ago. I will check the connections. My truck is an 01. 5 built late in the year and has the disk brakes all around, in case that helps anyone with what I should look for.



As a side note, I did have the IP replaced under warranty after I experienced the 'dead peddle'. That has been probably 60K miles ago.

 

[wtfd6]

if it has a ckp sensor it is between the starter and the block. fwiw I just replaced my IP and it didnt throw any codes.

 

[Missouri Mule]

rluft, your getting enough fuel pressure at VP44 you should not have to change fuel filter. You just need to see if fuel is getting to injectors.



Lugging is very bad for Diesel engines.

 

[rluft]

No fuel to the injectors. I opened the line to #1 cyl and not even a drop. The neg terminals on the battery were not tight so I tightened them, no change. The tach shows revs when cranking.



Perhaps you could elaborate on 'Lugging is very bad for Diesel engines. '. 'Bad' is a relative term which holds little meaning to me.

 

[wtfd6]

sounds like you lost a vp. lugging is where an engine is putting out about max torque at low rpm. its hard to really lug an engine with an automatic. much easier with manual. like trying to accelerate in higher gear at low speed.

 

[rluft]

Truck is at dealer. Diesel tech claimed the fuel system was full of air and after purging all the lines the motor runs. Question is, how did the air get in there. I have a lift pump at the tank feeding the lift pump on the motor which is less than ideal but has worked well so far. The tech thought they were causing air to fill the lines due to cavitation. What I think happened is I ran the tank out of fuel although the gauge reads 1/4 tank. I put 4 gallons in the tank when I got home to see if it would start which of course it would not with the air in the lines.

The tech is supposed to verify the amount of fuel in the tank and check out the gauge. BTW, I had a '99 Dodge gas motor that left me on the side of the road out of gas with 1/4 showing on the guage.

 

[icman95]

While it's a pain in the butt, the gauge reading 1/4 tank while you run out of gas may technically be right. You did say that you were going down hill and if the gauge is close to being right, but not exactly (they never are), the fuel may be low enough in the tank that when it sloshes to one side because of the hill, the pickup in the tank may not be able to suck it through the lines. Rare set of circumstances all coming together at once. Glad to see the dealer found the problem.

 

[PBrauer]

Diesel tech claimed the fuel system was full of air and after purging all the lines the motor runs. Question is, how did the air get in there. I have a lift pump at the tank feeding the lift pump on the motor... The tech thought they were causing air to fill the lines due to cavitation.

Just adding to things you could think about. Tech is probably part right, part wrong. "Cavitation" could be just a bad choice of words.



You said you had 16psi, which is good... Maybe too good??? Obviously the gauge will read air the same as fuel. There is always air in the fuel up to the filter/filter housing. Most of it should separate or "settle" out and end up going back to the tank via the return line. If the return line is blocked it could settle faster than it is evacuated. The bubble in the top of the filter housing reaches the top of the pick up tube, starving the injector pump...



I'd find a way to verify the entire delivery path/system, especially the pick up in the tank AND the return line "path". Probably have to improvise something, and probably need to drop the tank. Excess air is as bad as starvation on the inj pump. I'd take it seriously even though it's running now.



You could move the 1st, or put a 2nd FP gauge on the return line somehow... if the pressure is almost as high as the gauge at the inj pump then the return line is probably blocked, or partially blocked. You could also "vent" the return line fitting up front and see if your existing gauge drops substantially, but that wouldn't rule out blockage right at/inside the filter housing itself.



Although there is always some air, it should be a limited amount... random bubbles from sloshing, etc. Using the 2nd/extra pump is a good idea but if the pick up in the tank is partially blocked it will increase the amount of air that gets picked up, the lower the fuel level gets. The extra "vacuum" will "grab" and pass the bubbles through the blockage easier than the fuel. A little blockage at each end would make a good explanation too... Extra air being picked up, especially when the tank is low plus low return flow... it might have taken both to start to "accumulate".



The more I think about it, blockage at the pick up is probably the first thing (ideally) that I'd check... but since it means dropping the tank, I'd take the extra time to check the return path while I was at it. Initially, I was trying to think of something to check before dropping the tank.

 

[rweis]

The return line is not pressurized. The fuel is generally not hotter than 160*F. Any clear plastic tubing that can handle 160*, about 1/4 ID should work.



You can unclip the return line as it comes out of the engine T and push your clear line up on that double flare far enough to be able to put a couple of small hose clamps on it. String the clear return line back to the tank and stick it in the filler opening and secure it so it does not come out.



Crank up the engine and watch the clear return line for air bubbles (quantity). The VP44 bypass valve by design is mounted at the highest fuel point on the VP44 so it can purge air out of the internal VP44 fuel. Check the return fuel and see what you get.



All this procedure takes is about 10' of clear tubing, but gives you a pretty good idea of what the return fuel looks like.



IF it is a fuel level sender issue there are threads about repairing / cleaning / replacing that sender.



Bob Weis

 

[Missouri Mule]

rluft, lugging can destroy a diesel engine. (Running to low of rpms for gear your in and speed your doing, when this happens you need to down shift. )



Glad it was fuel/air in fuel system problem. Check and/or replace any rubber fuel line hoses. Check all connections.

If you did run out a fuel that should explain the air in the system especially if you tried to crank it after it died on you. (I cranked my Freightiner after it ran out fuel and I had to crack open a injector line to get it started. )

 

[rluft]

Truck is running again. The fuel level sender was bad and the tank was empty, with gauge showing 1/4. Appearantly the new sender is part of the in tank pump assembly. So now I have the pump in the tank, truck seems to be running well. Thanks for all the input.