Engine/Transmission (1994 - 1998) Timing Pin Removal

[crudd]

My Dad's '98 12 valve has what appears to be a broken off timing pin. What is the best way to replace the timing pin (i. e. how do you remove it)? Didn't have too much time to look at it, but figured I would ask here first.



Thanks.

 

[Reb.B]

is the whole timing pin broken and leaking oil, or is the nipple just broken off. There is a little keeper than holds it in, but if you pull hard ebough it will come out. The new will have an o-ring on it too, just plug it in and call it good. I usually grind the nipple off when i put one back in the engine. The timing pin is not reliable. The best way to check timing is to pull #1 injector and get TDC that way. You know when you are close when #6 exhaust spring is almost closed and #6 intake is starting to open. Vise versa when you want TDC #6 for setting the valves.

 

[crabman]

Part Numbers

crudd,

Here are the part numbers:

Timing Pin - 3903924 - $2. 92

O-Ring - 3913994 - $1. 30

Star Retaining Ring - 3904849 - $0. 37

Hope this helps you!

crabman



PS. Prices may be higher than posted but should be in the ballpark.

 

[Kernel]

Like said I wouldn't mess with it unless you are leaking oil, even then I would just buy a new pin with the o-ring push it in and say done with it. The timing pin on both my trucks come out completely and they haven't moved after just pushing them back in. When I talked to Cummins Rocky Mountain about the problems I was having with adjusting the valves on my 1st Gen they said they don't even use the timing pin, that it isn't reliable. They just pull the #1 and #6 valve cover and go from there. If you remove the small cover that holds the timing pin or that the timing pin goes in then there is a certain procedure you have to go through to get it back in the right place for TDC because the timing pin assembly housing is adjustable to match the pin up with the hole at TDC. If you do pull the assembly the procedure is as follows:



Look through the hole in the gear housing and rotate the engine util the hole in the camgear can be seen. Adjust the exhaust rocker to have zero valve clearance, remove the injector nozzles from all cylinders, temporarily install the vibration dampner, fabricate and install a wire pointer to the front of the gear housing so it points down to the vibration dampner. Rotate the crankshaft one-quarter rotation in the direction opposite engine rotation. Tighten the adjusting screw for the exhaust valve two complete turns of the screw. Tighten the locknut. Rotate the crankshaft slowly in the direction of engine rotation until the piston touches the exhaust vavle. Mark the vibration dampner corresponding to the wire pointer. Rotate the crankshaft in the opposite direction until the piston touches the valve and mark the vibration damper again. Measure the distance and mark the pulley at one-half the distance between the two marks. This mark is the TDC mark.



That is pretty much straight from the service manual and sounds like too much of a PITA to do to just use the pin. I would prefer just to look at #1 and #6 and go from there.



Scott

 

[Joe G.]

I never use the timing pin for adjusting valves. The valve overlap method that Scott describes works fine for valves. If I need to set timing the timing pin is not exact enough. I find TDC using the drop valve method for timing. The only use for the timing pin is to plug up the hole so it doesn't leak.

 

[Reb.B]

Yah, like i said, setting the valves with the valve overlap is more than reliable. If you want a timing mark, the best way i have found was to pull #1 injector, use a dial indicator and get TDC. Get some white paint and spray the balancer on both sides of the tach pickup. Get a razor blade and make a cut on both sides of the tach pickup. It is dead on, right on the money then. Then if you ever want to use a diesel timing light then, just shine it on the tach pickup and you can tell perfectly.

 

[Kernel]

That's a good idea Reb.



Scott