Cummins 5.9L diesel and the killer dowel pin (KDP)

   / Cummins 5.9L diesel and the killer dowel pin (KDP) #1  

flusher

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I'm seriously interested in a pre-owned Dodge Ram 3500 with the 5.9L diesel. Great engine, but the KDP problem is a worry.

http://www.genosgarage.com/GenosGarageTechArticles/TDR57_KillerDowelPin.pdf

From what I read previously, KDP is a problem for the 12 valve engine that was used in the 3500 through mid-1998 after which the 24 valve engine became standard. Now I understand that KDP can be a problem with the 24v engines also.

Has anyone had experience with or heard of someone who ran into the KDP problem in a 24v engine?

Has anyone installed the kit to fix KDP? The kit is pretty inexpensive

Dowel Pin Repair Kit for 94-98

but it looks to me like a real bear of a DIY project to install the fix.

Has anyone had the KDP kit installed by a dealer or at an independent shop? If so, what was the cost?

Thanks in advance.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #2  
Don't know a thing about the issue, but reading the instructions, is sounds like an easy repair. They say it takes 4 hours, for me I'd allow 8 hours. It always seems harder the first time you do something like this, plus it gives you a chance to get intamate with your truck.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #4  
There is another fix that I used and it was cheap. There is a fixture out there that allows you to drill and tap a hole and install a retaining bolt that lock the pin from moving. These were circulating around. I had mine done at Dave's diesel in Muncie Indiana some years ago. If you get on the TDR website you will probably learn about it.

It was very easy. A low pressure air was put into the engine and the fixture mounted. Then the hole is drilled and tapped and and the bolt is put in and locked. As I recall it was less than an hour.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #5  
I am a Dodge dealer. I have sold over a thousand Dodge/Cummins trucks over the years and have owned over 25 of them personally, ranging from 89's all the way up to 09's. I have "heard" of the KDP but have never actually seen one come out. Our shop business is about 75% Dodge/Cummins work and we've never seen the KDP issue come up. I have never actually talked to a real person who it has happened to, see a lot about it on the internet though.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP)
  • Thread Starter
#6  
There is another fix that I used and it was cheap. There is a fixture out there that allows you to drill and tap a hole and install a retaining bolt that lock the pin from moving. These were circulating around. I had mine done at Dave's diesel in Muncie Indiana some years ago. If you get on the TDR website you will probably learn about it.

It was very easy. A low pressure air was put into the engine and the fixture mounted. Then the hole is drilled and tapped and and the bolt is put in and locked. As I recall it was less than an hour.

Thanks for the info.

Fortunately, I'm a TDR member and can search the forums.
You're right, those jigs are still floating around and are available on loan to do the KDP drill and tap fix.

Reading some of those TDR threads, I get the impression that there are a few bolts under the timing cover that generally need tightening before they fall out and cause big time damage. And you need to remove the timing cover to get to those bolts.

So, my feeling is to bite the bullet, pull the timing cover off the front of the engine, do the KDP tab fix and tighten all those loose bolts. I don't like working in cramped spaces so I'll probably pull the radiator and remove as much of the front end as necessary to get the access I'm comfortable with. More work removing that stuff but I'll do it anyway.

All this KDP mess causes a drop in my esteem for the Cummins designers. Surely they are smart enough to make a design that doesn't have these problems. Why they didn't fix these flaws in the early 1990s when the KDP problem first surfaced is a mystery to me.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP)
  • Thread Starter
#7  
I found a YouTube video that helps understand the KDP problem regarding 12 valve and 24 valve 5.9L engines.

YouTube - Cummins KDP

The guy is using a 1999 24-valve engine for illustration.
Apparently Cummins added a lip feature to the KDP hole on the 24v engines that keeps the pin from working loose and causing damage.

However, the changeover from 12v to 24v engines occurred in mid-1998. According to this video, Cummins used the remaining 12v timing assemblies on the early 24v engines and these 12v assemblies did not have the lip feature to retain the KDP. And, I guess there's no way to be sure if a particular early production 24v engine has a 12v timing assembly except by pulling the timing cover off and looking for that retaining lip on the KDP hole.

So I guess the message is that, in order to avoid the hassle of installing a KDP fix yourself, stick to engines say from 2000 or later. That way you can be reasonably sure that the KDP lip fix is on your engine.
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #8  
I have never actually talked to a real person who it has happened to, see a lot about it on the INTERNET though.

My 96 is still running with the original KDP installed. Read about it on the INTERNET but didn't hear any talk about failures among owners and mechanics in my area so I worried a while and then forgot about it.:D
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #9  
. These were circulating around. I had mine done at Dave's diesel in Muncie Indiana some years ago. If you get on the TDR website you will probably learn about it.

It was very easy. A low pressure air was put into the engine and the fixture mounted. Then the hole is drilled and tapped and and the bolt is put in and locked. As I recall it was less than an hour.

Dave and his boy Darin along with his son in law Randy are good people. They all live on my road withing 1/2 mile of me. They love Dodges and know them inside and out. I drive Fords but they do not give me a hard time like they do those Dmax boy's.

Anyway good people.

Chris
 
   / Cummins 5.9L diesel and the killer dowel pin (KDP) #10  
Dave and his boy Darin along with his son in law Randy are good people. They all live on my road withing 1/2 mile of me. They love Dodges and know them inside and out. I drive Fords but they do not give me a hard time like they do those Dmax boy's.

Anyway good people.

Chris

I agree Chris, they were great to deal with. Very professional too.
 
 
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