Truck died again

[OLDBULL8]

Pull the IP solenoid cover off, it should be full of diesel. Hook up your 12V to the solenoid, make sure it is working. You can pull back the shut off slide by hand, spring should close it when you let go. About the only way to see if the input (IP drive shaft) is broke, take the front cover off the gear tower, turn the engine over by hand until the drive dowel is at 12 O'clock, clean and remove the cover on the side of the IP, stick a 5/32" hex key in, like adjusting the fuel, then see if you can move it up and down, should be NO movement, if so the shaft is broke. The last pic shows the drive shaft broken, this was the results of turning up the fuel and the screw head broke off. Not mine.
Just make sure when you put the solenoid cap back on, it's in the right position, see pic.

 

[Boston]

I'd be tempted to agree that the fuel return line should have fuel in it regardless of if the fuel shut off solenoid is working or not. Yet I have no fuel in the return line, and apparently no fuel getting to the engine as well. Although there is fuel getting to the input of the IP. Go figure.

The only possible conclusion is that the fuel shut off, prevents fuel from entering the fuel bowl. The return line is off the top of the IP body/bowl. So unless there is some bypass involved, the only thing left is that the IP isn't allowing fuel into the reservoir

I'll pop the top on it next chance I get, but something tells me I just need "another" new fuel pump.

 

[diezelcrazee]

Boston,
If I understand this fuel system correctly, the lift pump supplies a surplus of fuel to the injection pump and this gets returned out of the front of the injection pump. This occurs whether or not the solenoid is working. If that assumption of mine is true, if you pulled the return line at the front of the injection pump and cranked it, you should have fuel come out of the nipple. That will tell if the IP is getting fuel. Someone please correct me if I am wrong.

This is correct, by means of a passage which has a vent wire assembly in it, some fuel from the IP transfer pump should return into the upper housing and out the return elbow whether the solenoid is working or not. All the shutoff does is close the metering valve so that no fuel is delivered to the injection part of the pump. 12V to the solenoid overcomes the shutoff and allows the metering valve to deliver fuel.

Take a look at page 7 - 8 here for more info about the vent wire assembly: http://diezelcrazeesidipage.homeste...ce-Manual-Standadyne-DB2-Disassembly7-12.html

The pump has a screen in the inlet which is part of the IP transfer pump. Something could have it plugged, but it would have to be something that got by the main fuel filter. Take a look at page 10 in the above link and you can see this screen.

Other possibility, as Old Bull mentioned is the pump shaft. If it broke it would sure cause immediate shutdown! The shaft has a "fuse" (for lack of a better term) spot in it where it is small in diameter. It is designed to break there if something goes wrong. I doubt this is it, being you said it happened when you switched tanks.

 

[firehawk]

Seems to me the obvious problem (or at least where I would look first) is the tank selector valve.

 

[diezelcrazee]

I thought that to, but he says he is getting fuel to the injection pump......

 

[Boston]

I'm definitely getting fuel at the injection pump. I suppose I could check to see that I'm getting fuel from both tanks to the injection pump, but whatever tank it was on when I checked, does move fuel to the pump.

I disconnected the line going into the pump and placed it in a soda pop can to catch the fuel. Its definitely pumping fuel to the IP. Brand new carrier lift pump. Brand new filter. New lines, new IP, new injectors. Cleaned out both tanks and toweled out the inside of each. Rebuilt the fuel pick ups, cleaned the sending unit. Can't think of what I could have missed that might have left crud in the fuel system.

One thing I did notice was a slight surge and then it died. Very slight tho.

Q
if I take the inlet cap off to get at the screen, are there any special tools required to get it back together. Sounds more and more like I'll be buying a new pump anyway, but I'd like to check out both the suggestions that I crack a injector line and also check that filter screen. Or are there any special tools needed to get it off. If I'm understanding the drawing ( the resolution is a bit low so reading some of it is kinda difficult ) I should be able to simply unscrew the cap where they fuel enters the IP and find the screen over some kinda impeller looking thing.

 

[diezelcrazee]

if I take the inlet cap off to get at the screen, are there any special tools required to get it back together. Sounds more and more like I'll be buying a new pump anyway, but I'd like to check out both the suggestions that I crack a injector line and also check that filter screen. Or are there any special tools needed to get it off. If I'm understanding the drawing ( the resolution is a bit low so reading some of it is kinda difficult ) I should be able to simply unscrew the cap where they fuel enters the IP and find the screen over some kinda impeller looking thing.

I am hesitant to tell you to pull the end cap off. Reason 1 is the manual says to do this with the pump inverted so that the end cap is pointing up. There is some stuff in there that can fall out. I wouldn't think twice about it with the pump off the truck and standing upright, but on the truck.......probably not.

The other thing is contamination. You DO NOT want any dirt, debris, dust, germs and any other foreign matter getting in that pump, and to pull that cap and screen with it on the truck just isnt a clean enough environment in my opinion.

 

[Boston]

yikes. Well after all the trouble that "new" pump has given me, I wonder if its not just time to give up on it and get a real pump. I just can't imagine enough crud getting into it to clog anything. I cleaned and rebuilt the entire fuel system. Its all virtually brand new or thoroughly power washed and dried.

Nice call on the orientation of the pump tho, I'd have screwed that up completely if I'd have done it on the truck. If I gotta take it off anyway. I might as well just order a new pump and fiddle with this one later. I am curious to see what might be in there, seems more and more like a clog and that screen is a prime suspect.

 

[Black dawg]

with fuel pressure at the inlet, and no fuel at the return, I would pull the pump.

The first thing I would check is that the shaft isnt twisted off.
next I would pull the inlet and check the screen and transfer pump
if all of this checked out I would pull the vent wire and have a look at the other side of it. it is a very small orifice, and if it is plugged the engine will not run. I have seen this more than once.

 

[Boston]

Cold and rainy, I guess my only option is to pull the pump, but since I'm not tooled to fix anything other than maybe the screen. I might as well just order a new one.

 

[Boston]

Got the pump off today, but its kinda unwieldy and I've no great way to stand it up. Its amazing how fast though you can get something done when its the third or fourth time you've had to fiddle with it tho. Really looking forward to being done fiddling with it.

Some observations as I removed the IP.
There was a small needle pin that pushed against a spring like device in the fuel return fitting that screwed into the top of the solenoid housing. If the solenoid isn't working then the pin isn't moving and the return line won't allow fuel flow. This was not the case. I checked the solenoids again once I'd removed that fitting and the pin does move, whether it moves enough is another question but the pin does seem to be operating at least in some capacity. As I removed the injector lines from the injectors, not a single drop of fuel was in the lines. IE no leaking or dripping fuel. Once I'd removed the pump I was able to easily rotate the shaft and no fuel spilled out of the injection lines, although there was definitely fuel in the body of the pump as it was visible through the fitting port I'd removed from the return fuel line.

The pump is now setting with the lines still attached on one of my work benches. I need a way to hold it upright before I can remove the inlet area housing and inspect the filter scree. Maybe monday I'll build a jig or just set up some braces to hold it. Things kinda impossible to stand on its end tho, so I gotta dream up something or I'm bound to knock it over in the middle of everything.

Will keep you posted on what I find under the inlet housing.

Cheers
B

PS
The fuel return line does not function unless the solenoids are functioning, or at least the one that actuates the push pin.

 

[Boston]

OK so I finally had time to get the pump stood upright and take a few things apart. The screen was clean, but the impeller looking device under it doesn't rotate when you turn the main shaft, the one that attaches to the IP gear. I could rotate it independently and watch the four spring loaded paddles move, but it doesn't seem to work when you rotate the main shaft. So I'm inclined to say the shaft is broken, but I'm not very familiar with this IP so maybe someone can tell me what it does if its working correctly ?

Anyway thanks folks
Cheers
B

 

[Black dawg]

shaft is broken. How thick of fuel were you running?

 

[diezelcrazee]

X2 on what Black Dog said. If the transfer pump vanes aren't moving when you rotate the shaft, then the shaft is broken...time for a pump

 

[Boston]

I was running biodiesel with anti gelling in it. so not that thick. I had just flipped it over to motor oil, thick, but it hadn't time to reach even the lift pump let alone the IP. So it probably wasn't the fuel. Although I've run plenty of WMO threw it, and when its cold out, the stuffs pretty thick.

One thing I thought of as I was taking it apart, maybe using ether to start the vehicle caused the malfunction. It does kinda make the engine jump around some before it finally smooths out and runs. I haven't gotten the ether starting system on it yet, so I've just been firing a bit into the air intake every morning. Thing doesn't start if its under about 75°F and the glow plug system seems like a constant pain in the butt. So I kinda abandoned it and went with ether. Works like a charm but for the rough few seconds before start. But I'm not sure how it might break something like a shaft in the IP, I'd think that thing was farely robust.

Would thick fuel really cause such a major failure ? I could thin out the fuel some with bio and anti jell or maybe kerosene ?

cheers
B

PS
OH it was torture but I transferred funds to my credit card so I can just go buy a new one. 1k down the drain is a pain in the ass, but apparently the better part of thats gotta go to a new IP, rumor has it there's a few threads on where to go buy a decent one. So I guess I better go start searching.