help fuel pump fuel curve cam snapped, can I drive?

papadiesel

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I was replacing the TPS on my DB2 pump and saw the fuel curve cam? loose, (cast aluminum cam on the throttle shaft between pump body and TPS mount.) Mine is 7.3 idi with E40d. Can I drive it that way or will I burn pistons up? where can I get one, at work must drive home tonight, thanks
 

gandalf

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Let me recap what I think you have said. The problem is the shaft from the IP on which the TPS/FIPL mounts. Correct?

Then you've said two things which, in my mind, contradict each other. You've said that the shaft has snapped, and you've said that the shaft is loose. Which of those is what has happened?

The TPS/FIPL mounts on that shaft, and the TPS/FIPL controls the E4OD transmission and it's shift points. If the shaft has indeed snapped the TPS/FIPL loses all control over the transmission. I have no idea what happens in that case. I don't know if it is driveable, or if it will harm itself when driven. If the shaft is simply loose it will retain some semblance of control over the transmission. Again, I don't know what effect that will have, but I think nothing good. It may still be driveable to get you home, though the shift point may be rather strange. I certainly wouldn't want to drive it more than necessary to get you home.
 

papadiesel

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No it is the cam face that wraps around the shaft between the valve body and the TPS mount it’s a cast piece that gives an advance curve, it’s a cast aluminum piece with one Torx bolt going through it
 

gandalf

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Ahhh, I misread your statement. I suspect that piece is not quite so critical. I think I'd drive it, very carefully and rather slowly, only far enough to get home. If things go weird, if the truck becomes very unhappy, I'd stop and have it towed.

Now I'm thinking it must be the piece in the attached picture. Click on the picture, enlarge it, to see the torx head.
 

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papadiesel

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no, it is called a face cam, made of cast aluminum that the shaft goes through and rotates with the throttle shaft pushing a plunger for low trim fuel at low rpm, called the face cam. As I did research more, they can crack easily if tightened more than 35 in lbs. Mine was loose on the shaft so I "snugged" it up and heard a snap! I was concerned that it would overfuel, but keeping it in place will allow me to drive till i find a new one, thanks for your input!
 

Joezam

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That is the mechanical fuel advance, without you will experience lower power levels. Need to replace IP to fix.
 
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