Heavy Equipment Forums Heavy Equipment Community

Lock & Stitch block repair

Oxbow · 2023-06-14 22:26

Does anybody have experience using this method of crack repair? I have a crack in the block of one of our 4MG B models. It is about 4" long and at the back of the block, ending through the flange where the retarder mounts. It is not growing, but it is leaking oil beyond what is tolerable. I can get to it if I remove the oil filter and housing, as well as the exhaust down pipe from the turbo. With this system one drills completely through the block, so I would probably need to drop the pan to get any shavings out, which is a bit more of a chore with the retarder lines, but not too bad. I don’t believe it is in an oil galley. I will check with Cat in Pocatello tomorrow to see if they have the necessary kit. Cat does have a procedure for this repair, so if they are willing I will probably have them do it, but I had never heard of it prior to talking to the Cat branch manager in Idaho Falls today. He gas not done it himself and recommended Pocatello or perhaps Meridian stores. Anyway, I was curious if any of you have thoughts as to whether this can be done without pulling the engine, and I am interested in opinions. I would provide photos, but I cannot show the crack without removing the oil filter.

Replies6
  1. #1Coaldust2023-06-14 22:35

    The process has been around awhile. I watched a rep demo it, years ago. I used it on a Detroit series 60 that had a rod failure and it held up. I didn’t know that Caterpillar endorsed it. Whoduthunkit?

  2. #2Oxbow2023-06-14 22:42

    It's listed somewhere in SIS, as the kit has Cat part numbers as I was shown by the fella in Idaho Falls today, but I couldn't find it myself this evening.

  3. #3Coaldust2023-06-14 22:55

    That’s very cool. I’ll make a note of that.

  4. #4pushbroom2023-06-15 01:43

    I think this is the CAT procedure you are looking for. No experience with it but we have pulled engines to have a local machine shop weld them up and they have always turned out great and lasted. Had an ISX that was in an accident and snapped off the front comer of the block through 2 bolt holes. Sent it out to a welding shop and got a flawless repair. Engine is still running. I have no experience with lock n stich but always heard good thing about them

  5. #5Oxbow2023-06-15 07:36

    Thanks Pushbroom! Hopefully it can be done with the engine in the truck.

  6. #6Nige2023-06-15 11:11

    The earliest documentation regarding LNS on SIS goes back somewhere around the Millenium, so it's been around for a while. The fact that the document posted by @pushbroom is currently at CHG32 tells you it's not a new procedure.