Sun Aug 16, 2020 3:29 pm by cornbinder89
After looking around and asking about at shops, finding no one who wanted to take on the job, I pulled the head myself. Found a total of three head bolts snapped. On right under the head of the bolt, one right at the block surface and one 1 1/2" below the deck. 1st one came out with vice grips once the head was removed, 2nd I was able to turn with a punch and hammer, after 3 turns, enough was proud of the block that I could grab with vice grips and get it rest of the way out.
The last on was going to a bitch and I asked around at the best welder in the area but couldn't get someone to come and get it out.
An old Cummins mechanic told me to to take a valve push rod and cut a section out of the tube and put it down the hole and weld it to the stub. The Pushrod tube is a good fit and about the same size as the bolt.
I went to town and got some fresh 7018 rod. It took three tries for me to get it. 1st I had the current too high and blew through the side of the tube, 2nd had the current too low and it didn't hold, 3rd time wasn't great but it held and I was able to back the stub out.
I got my headbolt tap to chase the threads, and it went in hard. Taps don't last forever and depending on the hardness of what they are cutting can wear in as little as 10 holes. My hadbolt tap has done a few engines with over 30 headbolts per, it is time for a new tap. Two steps forward one back. After being successful in getting the stub of the headbolt out, it would be height of stupidity to snap a tap off in the hole because I was in a hurry or too cheap to get another tap.
The headbolts are 11/16x 16 TPI so is not a tap you are going to find at the local hardware store.
I ordered a new tap and pushrod to replace the one I sacrificed to the headbolt removal. I think I am going to frame that stub and tube, not because how hard it was to get out, but the confidence it took to try. When the best welder in the area didn't want to attempt, I was on my own, and if I was going to loose the engine, I am glad I wasn't paying someone to ruin it for me.
Once I chase all the bolt holes, drop a new head gasket on the block and get the head back on, it should go smooth.
There is some cracks on the piston crown not sure if they are from climbing the hill when the hose blew, or from before I owned the engine, but I am not going to inframe the engine now. I would burn some oil between oil changes before all this happened, and I suspect the cracks have been there for some time. Cummins allows for some cracking on the lands between the valve reliefs, which is where these cracks are.
If I were going to overhaul (which I am not) I would have it machined for lower press fit liners and then it would be a fairly bullet-proof engine. I just don't see me putting enough miles on to go through all the work.