Killer dowel pin and the fix

Whit

Registered User
Joined
Dec 20, 2003
Posts
3,808
Reaction score
0
Location
lost in Why-homing
article from diesel power mag

When it comes to diesel-truck lore, there are few things that are more aptly named than Killer Dowel Pin Syndrome. It's a problem that was initially reported on Dodges with the Cummins 5.9L from '89-'98 1/2 and is something that can have catastrophic results. During engine assembly, a steel dowel pin is pressed into the block to precisely locate its timing-gear housing. The problem? Over time, vibration can cause the pin to work its way out, and because it's made of steel, there is no working its way through the engine. It becomes the dowel pin of death.

the pin as you hope to find it


You must be registered for see images



There are a few things that can happen. Option number one: you get extremely lucky and the pin falls through the maze of cam, crank, and injection-pump gears and lands harmlessly in the oil pan or on the bottom of the gear housing-and nothing happens. Total cost for repairs: $0.

Option number two: the pin falls, and it comes in contact with the cam gear and smashes into the gear housing on the front of your engine. When this happens, it is steel versus aluminum-and steel wins out. The housing will crack open or lose a big chunk right where the dowel pin was forced into the housing. If this happens, you'll wake up the next morning and notice the Exxon Valdez in your driveway. Your total repair bill, including labor, will be approximately $1,000.

Option number three is the killer: the pin falls and munches up the cam gear or breaks it off completely. The valves will then smack into the pistons, creating a junkyard in your combustion chambers. Scraping metal doesn't work nearly as well as #2 diesel, and this can take out your heads, valves, and pistons-and possibly your engine block, making it impossible to overbore and rebuild. If this happens, there are almost no parts you can salvage, and your only option is to either to sell the truck for parts or pick up a new engine to the tune of at least a few thousands bucks. When option number three happens, you'll be left stranded on the side of the road.



Our '97 Dodge Ram cost $5,000, and we were really worried about option number three because we knew buying another truck might be a cheaper option than getting it fixed. While it may only happen to a few percent of Dodges, the killer dowel pin (KDP) can strike at any time, which is a huge worry for those using the truck for a business or driving long distances.

There are a dozen companies out there selling KDP repair kits (approximately $50) that consist of a new bolt, gaskets, and a tab to hold in the dowel pin so it can't work loose. The labor involved takes about two to three hours for a shop or about an afternoon if you are mechanically inclined and can do the repair in your driveway.

Basically, you have to remove all accessories from the front of your engine so you can get your timing-gear cover off, put in the dowel-retaining tab, then put everything back on. It's labor-intensive but certainly not too difficult. We meant to do this ourselves, but the narrow streets of Venice, California, are the only space we have to work on our truck. Finally, we realized that $200 of shop labor was better than the total loss of the truck and took it to Redline Diesel Performance in Corona, California, to have the dowel pin fixed. Now we can sleep at night.



The killer-dowel-pin repair kit consists of a gear-cover gasket, a new crank seal, and a KDP tab (arrow). Most kits also come with installation instructions; our kit from Piers Diesel Research had instructions that were accurate and well-written.
First, drain some coolant out so the upper radiator hose can be removed and the fan and shroud can be taken off. Later, this can be reused as long as you store it in something clean.
This is what needs to be removed to access the KDP. It's not too difficult, but there is labor involved.

You must be registered for see images


You must be registered for see images


You must be registered for see images


You must be registered for see images

You must be registered for see images
 

cfm

Registered User
Joined
Dec 28, 2008
Posts
17
Reaction score
0
Location
england
jeez....
is there any way of knowing which engines this is likly to happen to??
i m in the u.k. , and i have a 5.9 12v in my motorhome...
its done 500000kms, and was an ex prison truck- converted-
surely, after 500000kms the pin would have had more than enough time to drop out???
 

oldmisterbill

Grumpy Old Man
Joined
Nov 19, 2005
Posts
2,093
Reaction score
21
Location
Wagoner Oklahoma
I have an old motor home (134,000 miles).I wonder what percent of them have a problem. 1994 Holidaiy ramberler 36 foot . 5.9 12 valve 230 factory horse. 6 speed Allison. 137000 miles. Needs some love but really puppy type love.
I read about 2 other ways. 1. A set screw just thru the dowell pin boss At top of pin. Tighten and lock the lock nut. 2. weld aluminum nut inside the timing case in line with the dowel pin. Use a set screw tighten against the dowel pin, lock nut.
It’s going on a 4000 mile trip to Massachusetts in early spring. With 2 disabled elders. My wife and I. I am working on a dual back up on a 1000 or more converter to run my wife’s oxygen machine , and a large battery back up. The dowel pin has to wait till we are back. I am very limited to standing or under A vehicle work. It interestingly is rated at 230 hp more than most (I think). With a 6 speed Allison.
I have heard claims of 12 plus MPG because of the Holiday Ramblers wedge shaped front. Quiet on road but the deisel generator is partially in the dog house position. Noisy ****!
 
Last edited:

Forum statistics

Threads
91,263
Posts
1,129,513
Members
24,094
Latest member
madmustang1965

Members online

Top