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Discussion Starter #1
Have just replaced all the seals required to fix my two pump leaks from the Throttle Shaft, and the Manual Fuel Shut off, and installed a 3200 RPM Spring. Now with everything reassembled the truck will go straight to WOT upon start up. I made marks on the throttle linkage but they came off with handling. So I tired a few ways of dialing in the throttle shaft with no positive results. I have taking the throttle linkage completely off, started the truck which proceeded to go close to WOT, and tried adjust the throttle CW to reduce the throttle but this has also not caused the Engine to decrease in RPMs. It will rev higher, if I turn the shaft about half a turn CCW.

I really don't have a good diesel knowledge base, do not want to continue my seemingly worthless troubleshooting. Google hasn't yield any useful results for VE pump vehicles, as I get a lot of hits for Newer Electronic Cummins with High idle issues.

Any input wold greatly be appreciated.
 

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Are you describing runaway? Have you turned up the full power screw on the back of the pump? If the full power screw goes in to far it will cause runaway. Not sure if thats what you are experiencing.
Dave
 

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Discussion Starter #3
I have not purposeful adjusted the fuel settings, they may not be exact, however the are very close to stock.
 

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I know when installing spring I had to be careful when putting it back together, actually used a .020 feeler gauge to make sure everything was tucked in as top came down. I tend to agree with Lonno tho, sounds like backing full power out may bring rpms back down.http://search.yahoo.com/search?p=full+power+screw+runaway&ei=utf-8&fr=ie8 6th item down might help.
 

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Discussion Starter #5
Well, I took the top portion of the pump off again and then reassembled it without the throttle linkage, again not adjusting any of the settings. I started the truck, and it revved up rather high with no input then settled back down to normal idle... it ran fine for about five minutes, then I shut it down to put the throttle linkage back on.

With the throttle linkage back on, I would start the truck, and it would run then die. With about 1/8 throttle it would run fine. I adjusted the top idle set screw to keep it idling and went to take it for a spin.

The Truck has no power.. I have to feather the clutch, and pump the throttle to get it to move in first. This is obviously concerning as first was useless in the ZF and I could put the truck in third dump the clutch and the truck would bog and then chug along.


I feel that the throttle shaft may not be in the right position as I had to adjust the idle set screw slightly. However this doesn't explain the loss of power, my 1.6 Miata has more power that this truck currently.

Before I start looking into adjusting the pump settings to address the lack of power, is their something else I should be looking into and researching which may explain this?
 

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Before I start looking into adjusting the pump settings to address the lack of power, is their something else I should be looking into and researching which may explain this?

In my opinion, if you do that, you'll be introducing all kinds of new variables into your problem. Engine ran fine before and something changed. I would spend more time trying to get that throttle shaft positioned right.
 

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Did you pull the pump off of the gear housing or do it in place? Mikel is correct, no new variables. First it was WOT then it settled but no power and "the throttle shaft may not be in the right position". Must be in throttle shaft system.
 

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Ah I hate when you go thru trial and error well maybe not trial but error. Has to be something that was not put bask correctly. I have created my share of my own problems and when you figure out you than are expert..
 

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Waht kind of manual shut off did you put in for the ve?? Most have solenoid for shut off. Just curious if you made it or what?? Have not seen one on ve..
 

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Discussion Starter #10
I have no intention of adding variables, however till this point I haven't really been concerned with the need to adjust the pump. Stock the truck moved just fine.

The from what I can tell shaft is not more that a few degrees off, I just have a hard time understanding why I have no power.

In regards to the shut of valve, I was on the truck I didn't put it on. I looked up a Cummins VE pump Diagram, it showed that lever being a Manual fuel shut off. I have tried it, and it works...
 

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if the throttle shaft is off a position or two, it will lose power. try changing it one notch at a time.
This is why its VERY important to mark it before you disassemble it, or use a ball end allen and not mess with the throttle shaft at all.
 

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Discussion Starter #13
 

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Discussion Starter #14
if the throttle shaft is off a position or two, it will lose power. try changing it one notch at a time.
This is why its VERY important to mark it before you disassemble it, or use a ball end allen and not mess with the throttle shaft at all.
Why is this? It would seem to me that there is no definitive connection, just spring tension. Is the system that sensitive that a degree or two would cause such a drastic power loss?

What do you mean by using a ball end allen key? In what manner? The shaft had to be removed completely to facilitate the seals being replaced. Is there a better way to do this?
 

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Discussion Starter #16
Ah, well unfortunately in my case I had to as, I tore the throttle linkage down because the seals on the throttle shaft and the fuel shut off were leaking, no way around it as far as I can tell.
 

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I had a similar problem when I tore mine down to replace the same seals. Mine would start and idle fine, but, when I tried to rev it, it would die. Turned out I had the throttle shaft 180* out, so when I tried to rev it I was actually tripping the fuel kill. carefully take the nut off and start advancing it one spline at a time in either direction and see what it does. If it makes it worse, go the other way, if it makes it better, keep going, and yes, being one spline off does make that much of a difference. I tried to short cut it and jumped two splines on one move and I went too far, it was "idling" at about 2700 RPM. Backed it off a spline and it was perfect.
 

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Discussion Starter #19
This amazes me, I know very little about these pumps, however given the fact that there is no hard linkage; just a spring. I wouldn't think the pump would be as sensitive as it is.
 

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Discussion Starter #20
I tore the top of the pump down again, one to show my friend who was helping me what was going on inside as he just picked up a 12V Dodge and to reconfirm the the manual fuel shutoff was in the correct position as it wouldn't fully shut the motor down when I tired it.

After reassembling the top portion of the pump, we started the truck it ran fine and the fuel shut off works just fine as well, but again no power. I feel that the throttle shaft was in the right spot because the adjustment on the spline is just to great for it to be out of position as the idle, and throttle set screws are in their original position. At this point the only other thing which has been touched is the power screw. I turned it in about two threads, started the truck, drove it down the street and the power was back. I was able to pull out in second with no throttle and third with a little bit of throttle.

It is probably turn up just a little to much, as it smokes a little bit on take off and it didn't before. Needles to say, I am pleased that I can now drive the truck again and continue working out the gremlins and get the the next portion of the build.
 
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