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Discussion Starter #1
It sounded so simple! Remove the nut and washer on the injection pump drive gear, turn the engine with a barring tool till the keyway is in the 6 o'clock position. Push the timing pin in and turn the engine until the pin falls in the hole that markes #1 TDC.

OK, so I did all that, and have gone back and forth from the 5 o'clock to the 7 o'clock position with the keyway repeatedly, and no way does the pin fall into anything. The pin can be pulled out to a maximum of approx 7/8", then will go in about 3/16" before stopping. I expected the pin to encounter the hole and go in further when TDC was reached with the keyway in the 6 o'clock position. After wrenching for several hours looking for that elusive hole, I am thinking up new ways to describe the guys who made the directions sound so simple. Then I decided that I'm probably not the only guy who has had this problem.

I have WD-40'd the pin, and can move it in and out about 3/16" pretty easy with pliers so don't think it's a sticking problem. I hold pressure on the pin with various prybars while ratcheting the barring tool back and forth but there is no resistance or indication of the pin passing over a hole.

Questions that come to mind are:
1. First of all, am I correct in assuming that the keyway should be somewhere near the 6 o'clock position for the pin to fall into the hole?
2. Does the 7/8" total extension on the pin when pulled out sound about right, with it moving in about3/16" before hitting the back of the gear?
3. Is the hole the pin falls into a really tight fit so that perhaps the pin was installed off-center just enough it won't fall in?
4. If someone had sheared off the pin previously, wouldn't the pin travel be more than the 3/16" that I'm observing?
5. Why can't anything ever be as simple as it sounds?

TIA for your sound advice...!
 

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1 of 2 things here -

Either you are 180 out of TDC, or, more likely, the pin is broken. The tip that sets into the cam gear can be broken off an the only way you'll know is you can't seem to get the darned thing to seat. There is an o ring on it to keep it from coming all the way out. Its a bear, but a pair of needle nose pliers should be able to pullit all the way out. If there is not a little nub at the end, its broken. Get a new one from Dodge or your cummins supplier.
The other option is to find TDC via the valves. When cyl 1 is in overlap, you are at TDC. Not an exact science, but it works. Just mark on the pump where the bolts were so you can reinstall the pump approx where you removed it. The key will handle the rest.
 

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Discussion Starter #3
Thanks for your quick response! Is it possible to be 180 deg off with the keyway at the 6 o'clock position? Four cycles would be 2 engine revolutions, but should only be 1 camshaft rev.... or am I thinking wrong? At this point I'm not sure about anything and this is the first time I've done more than adjust the valves on this vehicle. It's been a great rig that gets over 20 mpg in the city with the AC running! My pickup is a 91 and only had 112,000 mi on it when I got it in 1999. Now has 145,000 mi. It always started instantly at the touch of the switch, and ran great but the IP started leaking out the front where the governor shaft plug is.

I will tighten the lock-down screw to hold the existing timing prior to removal, and have already made marks at the bolt holes. Is it possible to replace the front shaft seal while I have it out without removing the shaft and losing the timing on the pump?

Also, if I make sure the engine doesn't move, index everything carefully and reinstall the pump according to the marks, won't the timing be essentially the same as when I took it off? Sorry if that's a stupid question, but there's lots more about the timing thing on a diesel I don't understand than what I do.

Thanks for your input!
 

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I find the best way find TDC is by popping off the #1 and #6 valve covers and watching for valve overlap.
 

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I remove my front cover off of the engine everytime. It doesnt take long and is the best way to make sure it is in the right position every time. Also with the timing pin removed there is only one hole in the in cam that is not slotted you can use a bolt to hold the motor in time.
 
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