Killer Dowel Pin Revisited

[91W350]

I know this has been covered many times, I was curious though, what stops us from just removing the pin? I know it is an alignment pin, it seems though, that the bolts would hold the cover in place without the pin. I have two to do, so curiousity is killing me. Thanks, Glen

 

[Sri Ram]

Seems to make sense that given the pins are used to align the case during asmbly--as I've read here--they would no longer be necessary. But, I don't know…

 

[JLEONARD]

The pin would be hard to get out... . not much if anything to grab onto.

If the cover is off it's cake to stake it in place. Use a flat end punch and stake it in two places. . it will never come out.

Jay

 

[rlyons]

I would not reccomend removing the pins as they are there for alignment. The bolts are for clamping strength not alignment or shear strength. Just my opinion but I see no reason to remove them just in case just tab it and let her dig. Oo.

 

[DonTX]

Illumination needed

I am a newbie and keep hearing about the KDP, but have not found out which engines are subject to losing this pin. Should I be worried in my old 87? Where is the instructions for the fix located?

 

[Philip]

Any of the 12 valve engines are subject to the KDP striking. I think it was the 24 valves that got the new redesigned timing cover to prevent KDP movement.



This thread shows the position and how far you need to get into the engine to repair it.



https://www.turbodieselregister.com/forums/showthread.php?t=148013&highlight=KDP+repair



There are also issues with loose bolts in the same area. I would not recommend a jig fix.

 

[rlyons]

Don, check your email.

 

[91W350]

Thanks guys, I assume pulling the pin is not an option unless it has slid out to where one could get a grip on it. I cannot imagine the cover moving out of alignment with the bolts holding it tight and surely the bolts would be tougher to shear than the pin. I visioned this being a pin to help locate the cover and gasket during installation and not a structural part of the engine, or they would have enough stress on them to keep them from moving. Looks like just staking the ends of the hole would keep it from vibrating out. The tab fix looks like another metal part to work loose and worry about later. Glen

 

[MLee]

Thanks guys, I assume pulling the pin is not an option unless it has slid out to where one could get a grip on it. I cannot imagine the cover moving out of alignment with the bolts holding it tight and surely the bolts would be tougher to shear than the pin. I visioned this being a pin to help locate the cover and gasket during installation and not a structural part of the engine, or they would have enough stress on them to keep them from moving. Looks like just staking the ends of the hole would keep it from vibrating out. The tab fix looks like another metal part to work loose and worry about later. Glen

One must remember, or have pointed out, that 18ft lbs is not much pressure to hold this case in place, of which the pin does [as a guide pin] and also does the supporting of the part. I think in time you will have far more trouble if the pin is removed and left out. Cummins says to replace the pin for this very reason, for alignment on the case. And I believe they should know what is best.

My penny's worth--stack it -- Tab it and be done with it. OHHHH check those bolts too.

Marv.

 

[Greenleaf]

Something that has not been adressed in some time is the likelyhood of loosing a dowel pin.



The 5. 9's with the P7100 are most suspect to loose the pin as opposed the the older engine. This is due to the difference is the case designe, NOT because it has a bigger pump as some seem to believe.



The fact of the matter is this; The older style timing case was cast with more "meat" in the dowel pin area. It simply takes longer for the pin to work it's way out because it has a longer hole to travel through. Think about that for a moment. It just makes perfect sense.



We commonly refer to this extra case material as the "step" next to the case bolt. The newer engines employed a case with no "step". There is not at much material. It's flat in that area next to the case bolt.





And by the way, the tabe can't work loose because it's held in place by the case bolt. Should you NOT clean and loc-tite the bolt, then yes, it will work loose and the bolt will no less cause more damage than the tab.