Main bearing ordeal solved

Just saw a post below asking if I had solved the problem I was having getting the one main bearing back into the engine. Short answer, yes, I finally got it.

The long answer, is yes, I got it, but it was a royal PITA. I wound up taking the bearing back out of the #2 spot, and putting it in the #4 spot. The second bearing was still tight, and did pretty much just like the other one did. I got it in by bending a heavy cotter pin and putting it in the oil hole where it would hit, and carry the bearing around as I turned the crank. I then used a hammer handle to put pressure on the bearing shell to keep it against the crank journal as I turned the crank. I"d go just a little bit, and then tap the back of the still exposed bearing shell by hand with a small brass punch. Eventually the bearing went in.

I then moved on to getting the shell that originally gave me problems into the #2 spot. I chose that spot because it was the most easily accessible. It did the same thing in the #2 spot as it did the #4 spot, and stopped about half way in. I used the same technique I described above to finally get the bearing in. It took a bit, but it eventually went.

When I got done getting them all in the crank turned just as easy, and smooth as it should, and the engine ran like a top. The only thing I can think that would have caused the problem is that the top shells has a slit cut in them length wise to open the oil passage into the bearing, and it"s possible the bearing was tweeked just a touch right at the end of the slit. The shell would go in just past the end of the slit every time before stopping, and did the same at both places it was tried. I think the difference was that the #2 spot was able to open up a few thousandths more than the #4 spot because of the distance from the transmission shaft, which would have been supporting it, thus allowing the shell to slide in where it wouldn"t otherwise have been able to.

thanks for the update. Bill

Thanks for the follow-up Wayne. I remember now that I had a little difficulty once with them not wanting to stay on the crank, and lift instead.

Thanks for the update, it's good to hear you solved the problem. Someone else might need to use your procedure.

Thanks for letting us know. Rolled in a good many with a bent cotter pin some snug, but never as bad what you experienced.
Ron

Thanks for your reply-I've had a few that went hard, almost as exactly as you described. I didn't understand why either-just figured something was a few thousandths off just like you did.Glad it went ok! Mark

I can relate to bearings being a PITA. Found out years ago doing in frame truck diesel rebuilds, if you loosen all the fan belts that run off the crank it makes a difference. Used brass brake rivets whenever possible as they would shear easy and not damage the inserts. The biggest thing to look out for is to put the correct insert in and you'll have few problems. One other item with Cummins and Mack engines was to run the main caps up lightly with an impact wrench, loosen the bolts up and do it again to get the caps centered before torqing them!