12V Cummins KDP Cracked Timing Case Replacement 

derek czeschin Yes. I had this same question and it does not affect the head gasket seal. You install ARP head studs by pulling and replacing head bolts one at a time. Just follow the proper steps when reinstalling and there shouldn’t be a problem. Mine has been fine for 10k+ after this 👍🏻

Working All Day I did not upgrade the cam or head stud it. Would’ve been a good time to do that though! Yikes, could it be front main or oil pan?

DoubleWrench I’m guessing you can’t undo the cam sprocket to remove the timing case? (Instead of pulling the whole camshaft)

Working All Day I think you can with some special service tool, but it’s an interference fit and you have to get the gear very hot before pressing it back on. I think that’s what Cummins dealers do but wasn’t an option for me

SIRj since the pushrods are out the lifters should be able to move any amount you want. Once dowels are in solid get em up as high as you can. Try gently wiggling around and twisting, a lobe could be snagging a cam bearing?

DoubleWrench ok thanks. Some of them move a lot, others are only coming up just a little. I can only get my cam shaft to come out about 2” then it almost acts like it hanging up on something.

SIRj sounds like it’s getting hung up on the cam lobes. You have to push in on the bottom of the sprocket and pull out on the top to “lift” the cam inside the engine

Nathan Reynolds not too bad if it was at TDC when you pulled the p pump, so you can get it back there and pop the pump on, otherwise I guess you’ll have to time the pump?

WeepWeep 222 yo man, I think it should be fine and you could just add more JB weld. The damage is done, most say the dowel is only necessary during assembly and once in place, the timing case has enough other bolts and dowels to not move. Your dowel is most likely just chillin in the oil pan not doing any harm. I did the full blown replacement because I didn’t want to be the perpetrator of a JB weld hack job, but since yours is already like that I’d try more JB first. If you commit to this job it really isn’t that bad, and you learn a lot about your engine!

DoubleWrench I appreciate your response man. Yeah I went to do the kdp and that’s when I realized all the bad news 😔 sad thing is, he had all broken gears replaced by some shop and they put it back together like this. I don’t understand why someone could do that much work but not change the case out, but I could wonder all day hahah but maybe they had there reasons. I loved the video and I love the truck so when the funds are available as well as the time I’ll get her done. I’m currently restoring this 97 3500 dually single cab back to get former glory. She has 4:1 gear ratio and let me tell ya hahahah highway speeds are not to impressive. I think I am pushing 2000 at 65 does that sound about right?

WeepWeep 222 sad, no excuse if they had it that far apart! Oh well, it really isn’t that bad or expensive. I put an eBay case on and it’s been fine. If you’re restoring it this is the way to go for sure, and you can tackle other important stuff while in like water pump, lift pump, maybe advance IP timing, etc! Not to mention painting everything! I’m not sure what rear I have, but 65-67mph is 2k rpm for me. All stock besides straight pipe (just 3”), turbo silencer ring delete, and advanced timing and I’ve cruised at 78mph or 2300rpm with a trailer with no issues. Excited to get a new clutch in so I can fuel plate and gov spring it!

DoubleWrench hope to see more videos man! And yeah I’m going to do it hahah! Paint parts red since the truck is red, I installed a new turbo (stock hx35) new injectors from ddp big honkin air filter, new water pump flushed radiator new thermostat, harmonic balancer, rear fenders and now got this on the list yay haha. Would love to see more videos brother I believe I subbed to ya!

I believe 1/2”

@@doublewrench69 3/8 pine x 12 " dowel rod 3/8 x 3/8 magnets superglued on them got my magnets off amazon

Sam diesel sd e350 the killer dowel pin came out and rode around the cam gear. Luckily it didn’t make it all the way to the crank gear or the engine would be toast!

Hey Jonny Sokoloski thanks for your response I just got in to the same situation so I am getting my self prepared for this I already open the first cover. My kdp is in but the bolt what was holding it is not on fortunately is not damages on the gears ⚙️ but so I have to find the bolts I hope is in the oil pan. But thanks for reply.... and nice very helpful video men 👍🏻.

Sam diesel sd e350 Sorry to hear that but that is another cause as you have found out. Make sure to use plenty of loctite on the timing case bolts when they go back together and torque to spec (18ft lbs I believe)! If you can’t find the bolt it shouldn’t be too hard to track down. If you come up with any questions feel free to ask!

Sam diesel sd e350 oh, and if your case isn’t broken that bad (just a crack), a friend of mine was able to use JB weld! It’s not as good of a fix but it’s a lot quicker and easier and has lasted a couple years so far.

Jonny Sokoloski kind same process to replace the cover but thanks for the advice...