Attention: TDR Forum Junkies 
Take care of it before it's too late
Don't delay on containing your dowel pin, the damage that little sucker can cause to your 12 valve and 24 valve up to '99 is severe. To see the damage and why it costs so much to repair click this http://www.flex.net/~triplem/new/dowelpin.htm
What is a killer dowel pin? it is the Upper Timing Case Dowel Pin
In the back of the timing gear case, there is an assembly index pin pressed into a hole. Some holes do not fit tightly around the pin and the pin can vibrate out of the hole, then fall into the gear train. The pin is then rattled around by the timing gears until it either falls into the oil pan (rare), gets kicked out through the side of the timing case, or passes through gear train bending the camshaft and ruining the gears and case causing extensive damage. A small number of 12 Valve engines have encountered this problem but the repair is very costly, $1200 - $4000
Response from Cummins on this matter
"The timing pin diameter from the supplier and the hole drilled for the pin, are designed to be 'press fit' dimensions. In some cases, the supplied timing pin dimension and the drilled hole dimension, may not provide the correct 'press fit'. During assembly line manufacturing, it is impossible to determine the amount of 'press fit' between the pin and the drilled hole, once the pin is installed into the bore.
Some of the pins have not had the correct 'press fit' in the drilled hole and have worked out of the hole. This does cause extensive damage to the gears and gear cover. The percentage of failure is low and did not justify a major recall campaign of all engines. If an unexpected failure should occur during the warranty period of the engine, the repair will be handled under normal warranty practices.
Early in 1998 the gear cover was changed to a 'blind hole' design, which would not let the dowel pin move out of the bore. If you have a great fear of this pin coming out, we suggest discussing this issue with your local Dodge dealer or Cummins distributor, to determine the appropriate action in each situation.
The pin itself can be replaced if desired or Locktite can be used to hold it in place, without having to replace the pin or gear housing assembly.
Inspection and securing of the timing pin:
1. Remove the damper, pulley and gear cover from front of engine.
2. Tap on the dowel pin with a flat punch to insure that it is seated in the bore.
3. Clean all the oil from area with solvent and dry completely.
4. Apply some wicking type Locktite on the dowel pin and housing and let the Locktite cure.
5. Reinstall the cover with a new seal and gasket.
6. Reinstall damper and pulley.
We hope this helps you understand the dowel issue better.
signed Cummins"
Members here are a picky lot and don't trust Cummins' Loc-Tite fix nor believe it is a rare problem. The best ways of preventing the pin escaping are the jig fix and tab fix. Both methods work equally well and have their own advantages. The jig fix is faster, easier and basically free. The tab fix also allows you to tighten any loose bolts under the case cover and you can do it on your own time, no need to wait for a jig and pass it on to the next user. You do have to buy new seals and it takes longer than the jig fix.
For info on the tab fix contact Joe G at -- email address removed -- for excellent instructions.
Click here for a diagram of how the KDP tab is made.
For those who do not have the facilities to fashion their own tab, You can go to Cummins and ask for Part# 3958017. It should be less than a dollar.
If you are interested in getting on a list for use of a KDP jig just click on the name of the caretaker in your area and send them a message with your name, mailing & email addresses and phone number. Mailing the jigs is what takes up the time, try to make a get together out of it and kill many at a time.
Please do not ask to use a jig if you feel you can't use it in a timely manner, others are waiting!!!
If you are waiting on a jig and plan an extended absence let the jig caretaker know so the jig isn't mailed to an empty house and gets stuck.
illflem - Northwest
Big K- -- email address removed -- - Seattle area
Danelle - Calif & Southwest
tp0d - Northeast
Cooker - Midwest
TFabian Virginia and surrounds
FreeBMW (Clayton)-Southeast
Rammin On- Mason-Dixon Mid Atlantic area
PM MLee (Marv) - Rocky Mtns
Gitchesum(Curtis Harris)-Texas and SouthCentral
CPFF is the master machinist to contact if you'd like to purchase a jig, care take one in an area not covered or just thank him for his excellent work that benefits us all.
Don't delay on containing your dowel pin, the damage that little sucker can cause to your 12 valve and 24 valve up to '99 is severe. To see the damage and why it costs so much to repair click this http://www.flex.net/~triplem/new/dowelpin.htm
What is a killer dowel pin? it is the Upper Timing Case Dowel Pin
In the back of the timing gear case, there is an assembly index pin pressed into a hole. Some holes do not fit tightly around the pin and the pin can vibrate out of the hole, then fall into the gear train. The pin is then rattled around by the timing gears until it either falls into the oil pan (rare), gets kicked out through the side of the timing case, or passes through gear train bending the camshaft and ruining the gears and case causing extensive damage. A small number of 12 Valve engines have encountered this problem but the repair is very costly, $1200 - $4000
Response from Cummins on this matter
"The timing pin diameter from the supplier and the hole drilled for the pin, are designed to be 'press fit' dimensions. In some cases, the supplied timing pin dimension and the drilled hole dimension, may not provide the correct 'press fit'. During assembly line manufacturing, it is impossible to determine the amount of 'press fit' between the pin and the drilled hole, once the pin is installed into the bore.
Some of the pins have not had the correct 'press fit' in the drilled hole and have worked out of the hole. This does cause extensive damage to the gears and gear cover. The percentage of failure is low and did not justify a major recall campaign of all engines. If an unexpected failure should occur during the warranty period of the engine, the repair will be handled under normal warranty practices.
Early in 1998 the gear cover was changed to a 'blind hole' design, which would not let the dowel pin move out of the bore. If you have a great fear of this pin coming out, we suggest discussing this issue with your local Dodge dealer or Cummins distributor, to determine the appropriate action in each situation.
The pin itself can be replaced if desired or Locktite can be used to hold it in place, without having to replace the pin or gear housing assembly.
Inspection and securing of the timing pin:
1. Remove the damper, pulley and gear cover from front of engine.
2. Tap on the dowel pin with a flat punch to insure that it is seated in the bore.
3. Clean all the oil from area with solvent and dry completely.
4. Apply some wicking type Locktite on the dowel pin and housing and let the Locktite cure.
5. Reinstall the cover with a new seal and gasket.
6. Reinstall damper and pulley.
We hope this helps you understand the dowel issue better.
signed Cummins"
Members here are a picky lot and don't trust Cummins' Loc-Tite fix nor believe it is a rare problem. The best ways of preventing the pin escaping are the jig fix and tab fix. Both methods work equally well and have their own advantages. The jig fix is faster, easier and basically free. The tab fix also allows you to tighten any loose bolts under the case cover and you can do it on your own time, no need to wait for a jig and pass it on to the next user. You do have to buy new seals and it takes longer than the jig fix.
For info on the tab fix contact Joe G at -- email address removed -- for excellent instructions.
Click here for a diagram of how the KDP tab is made.
For those who do not have the facilities to fashion their own tab, You can go to Cummins and ask for Part# 3958017. It should be less than a dollar.
If you are interested in getting on a list for use of a KDP jig just click on the name of the caretaker in your area and send them a message with your name, mailing & email addresses and phone number. Mailing the jigs is what takes up the time, try to make a get together out of it and kill many at a time.
Please do not ask to use a jig if you feel you can't use it in a timely manner, others are waiting!!!
If you are waiting on a jig and plan an extended absence let the jig caretaker know so the jig isn't mailed to an empty house and gets stuck.
illflem - Northwest
Big K- -- email address removed -- - Seattle area
Danelle - Calif & Southwest
tp0d - Northeast
Cooker - Midwest
TFabian Virginia and surrounds
FreeBMW (Clayton)-Southeast
Rammin On- Mason-Dixon Mid Atlantic area
PM MLee (Marv) - Rocky Mtns
Gitchesum(Curtis Harris)-Texas and SouthCentral
CPFF is the master machinist to contact if you'd like to purchase a jig, care take one in an area not covered or just thank him for his excellent work that benefits us all.
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