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Dowel Pin that Killed

2K views 13 replies 7 participants last post by  illflem 
#1 · (Edited)
I just want to assure everyone that I have searched this sight (brilliant group of people by the way and thanks in advance) and I have found most of what I need but it seems a times, the person replying to a post assumes the reader (in this case me) knows what the heck they are talking about.

I hope someone out there can find the time to give me a detailed answer.

Long story short: purchased the truck for towing several months ago. It was sold to me with 203,XXX miles but after seeing documentation not revealed to me until after purchase, I'm assuming the truck has upwards of 300K on it. After reading about the KDP I decided that once I have time to tear into it I will do so asap. I was hoping for winter. As you can guess, the dowel pin beat me to the punch (aka CRUNCH). Big ol' chunk out of the timing case.

I have removed everything from the ac condenser to timing cover. I have aligned the cam gear with the crank gear and removed the gear on the IP. There are two bolts hold the vacuum pump to the rear of the case which I have removed along with three out of the four nuts holding the IP to the case (only one I have left is the lowest passenger side nut). Is there anyway to remove that last nut without pulling the whole pump? If not, how exactly do I pull it off? You guys are great and very knowledgeable but this is the most intrusive engine work I've encountered.

I already have the valve covers off with 1/2" dowels ready to hold the tappets for me to pull the cam. I'm four days into this project and I'm feeling doubtful (at the same time I'm also feeling pretty good that I've gotten so far).

I have also read that the lift pump needs to be removed to allow clearance for the cam. Is this true? I haven't been around an internet connection for awhile and called a diesel shop in Colorado (only one within 500 miles that didn't focus on fluid changes and regular maintenance) and a tech there seemed to know his stuff and told me that by using dowels to hold up the tappets I would be able to remove the cam without messing with IP or lift pump.

If any of you could give me some details or pictures (doubtful but hopeful) I would be much obliged.

One last question, I have all the gaskets for the block to case and case to cover but I have read on here that a few of you prefer some sort of non-hardening RTV. Is that in addition to the gaskets or instead of?

I once again thank all of you on this forum. I try not to ask many questions seeing as this forum is already top notch if one uses the search function.
 
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#2 ·
#3 ·
In all honesty, after the work I put in, I'll be ticked if I don't have to pull that cam :doh:

Currently I am in no position to just pull the gear off of the cam. I will have no way of heating it up. My current situation (girlfriends garage) is no where near the shop I'm used to.

I have read that exact post several time and reading it again now I see that the last bottom nut holding the IP to the case can be reached with a few swivels on a socket set (it often takes a few tries for things to set in for me).

I suppose after all is done with that last nut on the IP, the only thing keeping the gear case from coming off is the cam/cam gear. I have all the tappets up and ready for action but I just can't figure out what to do with the lift pump. I honestly just don't get it. I apologize for being so uneducated about it but does it have to come off to allow the cam room to slide out? If so, how? After a few days in a garage (reason I call it a garage isn't because of the tools or amenities, but only because that's what a realtor would call it) I'm about to pull my hair out. I do one step at a time and then second guessing myself, I clean the grease and grime off me and log back into the forums.

I do appreciate your quick reply.
 
#4 · (Edited)
I can understand getting that far and not having to pull the cam. Its irritating, however if you don't have the tools to do it the other way correctly, pulling the cam is just fine too. Just takes a bit longer.

Remove the lift pump completely, especially if you have never pulled a cam before and dont fully understand how the lift pump functions, ciritical step some forget. There is a piston/plunger that sits on a cam lobe that is designed for the lift pump. As it comes around it pushes the piston in (much like a pushrod but horizontal) creating a negative pressure allowing fuel to be pulled into the pump. The spring pressure of the return stroke of the piston is what delievers fuel to the injection pump. Here is a write up on how the pump functions.

Tork Teknology Article Number One- The Cummins Lift Pump

Just two bolts that hold the lift pump on. It must be removed completely to allow the cam to slide out without binding up, the plunger can get and usually will get hung up on the bearing journals.
 
#6 ·
You have to pull the IP to change the gear case anyway. Removal is much easier if you also remove the injector lines from the injectors and lift from the engine as a unit. Also remove the fuel filter. After you get the fuel filter off, follow the fuel return line (rubber) back toward the pump. It is attached to the hard fuel line you disconnected with the OFV. That line is attached to the pump with a bolted bracket. Either remove the bolt or disconnect the rubber hose. I mention it because my FSM didn't. It also didn't mention removing the throttle rod from the linkage if you plan on taking it completely out of the engine bay. Be ready for it when you remove the IP. It weighs 44 pounds and has a quart of oil in it that will come out the front when tipped.

When we replaced the gasket on my case we did not use any RTV and it hasn't leaked in over 400k.

If the lift pump has never been off before plan on the fittings to be TIGHT! For ease of reassy get a pair of hardened studs to replace the bolts, 55mm long, and nuts. A good time to replace the L shaped hose (about $7 from Genos) and clean the prefilter strainer.
 
#7 ·
Thank you Whiskey for the link to the lift pump info. Very informative. I feel like I have so much more to do (always a good thing).

Drunk, I will be pulling the cam for sure. Had I the proper tools and previous experiences I'm sure the cam gear removal would be easier and quicker.

I appreciate the detailed information, GAmes. What is the OFV and FSM (sorry guys, like I said, I'm not very knowledgeable) and can I get away with just pulling the lift pump instead of removing all the lines and IP? It may sound lazy but I just have parts everywhere on the floor of the garage, don't really want to get in much deeper than I am now.

Thanks again.
 
#8 ·
What shop did you talk to in Colorado?
 
#9 ·
I don't recall the name. The closest big city to me is Kansas City. I called five there with the techs sounding confident over the phone until I asked my detailed question. I broadened my horizons and started calling any shop I could find online. I don't remember the name of the shop but it is located in Parker, CO. Guy knew his stuff up until he said that only the tappets needs to be lifted in order to pull the cam and not to mess lift pump or injection pump. Not saying he is wrong, I'm just getting varying advice from smart guys all over. I'm not scared to admit this is the biggest job I've taken on alone and ,although it feels good to do it myself, I feel like I'm just staring at a bunch of bolts and deciding at random what needs to come off.

Like I mentioned earlier, I have just one nut left holding on the gear case (the bottom passenger nut on the IP) and then the case will be free other than the cam holding it in. I'm searching for pics and details on LP removal now so I don't screw anything up. Just hoping I don't have to pull the IP and all the lines. I know it may help but being one nut and cam away... argh!
 
#11 ·
I'm not replacing it with a new pin. I am going to use the same pin. It never fell through the gears. It just rode the cam gear for a mile or two wearing on the aluminum case. Compared to the pictures I've seen of new ones and no where close to buy a new one, I think (hope) it'll be okay once I put it back in and tab it.
 
#12 ·
FSM is factory service manual. Best money you will ever spend if you don't have one.

Is your plan to leave the IP balanced on the two lower mounting bolts? I never thought about doing that. Those bolts go into a bracket that is attached to the block bracket by ONE bolt that isn't very big. I'm not sure that braket will hold the weight. You definitely need to secure it somehow. We removed the IP from the engine completely.

The nut you have remaining is easier to access if the injector lines are off.

The dowel pin is a press fit. If it is worn it needs to be replaced. Not that expensive.
 
#13 · (Edited)
By golly it is finished. Fixed? no. But I have removed the cam and pulled the broken gear case (replacing the cam asap, I just don't trust dowel rods and rubber bands). I have finished the take apart section. I now await parts and then then come the questions for the assembly.

I thank everyone who replied. I will just state that the IP does not need to be pulled. The lift pump is a different story. I removed the two 10mm bolts holding it in place with a 1/2" dowel (remaining from the dowels to hold the tappets) between the pump and block. Just enough room. The IP, I didn't need to move other than the four nuts holding it onto the gear case. Other than that things went very well.

I have several pictures and want to do a write up for the common man (I use this term loosely because most of you consider yourself back yard mechanics yet you still confuse me). I have taken a few pictures throughout the process and I hope it will brings sense to some other unlucky victim of the KDP.

I once again thank you guys for being so supportive of my issue and being as detailed as you can. I hope to pay if forward asap.

I am now awaiting parts and paintingn covers and other misc. items.

This forum is great!!!!
 
#14 ·
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