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I see a crack between a headbolt and passage.

There are two head bolt/water passages that have a discoloration from previous head gasket leak. This shows as a crack. There is no crack at those two points. The picture is deceiving. I am however having intake seats installed. Shown are two seats in the block that were ground, but I was not happy with the condition afterwards. These did pull and hold vacuum, but I felt that they may burn through at some time in the future.

That crack he is talking about appears in the before AND after pics of the block surfacing. Not easy to see in the before shot since that set of holes is a cylinder further down but sure looks like it is there in that shot also. I know we are armchair quarterbacking here but I am seeing a pattern of stuff that should not be coming out of a quality machine shop, especially that valve seat. It appears that the area below the head bolt is all part of the same water passage so the crack may not be too much of an issue, there will be water below the bolt anyway. There does not really appear to be enough meat there to hold a Helicoil that effectively. I would be sure to use Permatex liquid teflon on the bolt threads to at least try to seal it up a bit and be sure to run antifreeze to prevent rust.

I DO appreciate the comments/concerns of everyone from this forum, wether "arm chair" or other.
I will be using Permatex #2 on all head bolts and studs, since they all run into water jackets. I have seen many of these blocks with the heads removed, all had pitting on the tops of the valves, pistons and deck from cooling water leaking past the head gasket, or the head bolts.
The head bolts were purchased new, as well as the intake/exhaust studs. This engine will get 300 miles/year of driving. No speeds over 40 mph, the 583 gears forbid that. Tomorrow the crank/bearing clearances will be checked. Looking for ~.0015 or so spacing. Thinking of using the Delco (or equivalent) 15w-40 oil for break-in. The Diesel oil has a higher zinc content. Any thoughts?
Thanks again.

That is what I would use. There has been a lot of discussion about whether zinc is actually needed in the older engines along with sulfur but I look at it this way, If they are still leaving a little in the diesel oils they are doing it for a reason, to keep those very expensive big diesels alive. That is good enough for me to use it myself. I have gotten 400,000 miles on three different pick up trucks using Rotella 15W-40 oil. I also ran it in a fleet of vans and pick ups that I was in charge of and never had an oil related failure. And these people were hard on these vehicles. One thing to watch for is adding zinc additives because too much is bad. The oil additive package in the oil is well thought out, go with that alone, no additives.

getting .0015 would be great but the machines used by most crank grinders dont get them that close like the factory machines did/do. these days I am happy between 2 and 3 thou

Using the green Plastigage, which is rated from .000-.003" I measured .002" on all except the rear main bearing. The last bearing clearance was just under .002" clearance. There are more accurate ways to measure bearing clearance, but this was the system that was available at the time.

The Sealed Power .060" over size pistons are pressed on the rods, and Hastings rings mounted on the pistons. The pistons with wrist pins all weighed in at 571 grams. This along with the crankshaft-flywheel-clutch pressure plate balancing, should help with a smooth running engine. The conrods had a weight variation of 7 grams low to high. The previous set of conrods varied 20 grams.

Back from the vacation. Crank, oil pickup, oil line, Cam, installed into the block. Had to do some light work on the front camshaft bearing. When the cam was installed fully, it was very hard to rotate. The front bearing had a tight spot that needed clearance work. There was s section that was "shiny" on the bearing.

Looks like things are coming along nicely. FYI the Sealed Power pistons have .020" less compression height then stock. If you're milling the head and care to do some measuring raising the compression is free power and MPG. The chambers on my current motor are 80cc and yield 8:1.

.020!? That is a substantial reduction in compression from stock which was already very low. Why would they do that? Are you sure it is .020?

Just measured the factory piston top to top of wrist pin- 1.565"
The new Sealed Power pistons are 1.545"
Delta .020"
The new pistons will sit twenty thousandths deeper in the hole.
Glad I milled the head .020" and the deck .010"
Pistons made in India, all six measured 571 grams with wrist pin.

ashyers wrote:Looks like things are coming along nicely. FYI the Sealed Power pistons have .020" less compression height then stock. If you're milling the head and care to do some measuring raising the compression is free power and MPG. The chambers on my current motor are 80cc and yield 8:1.

Ashyers, do you recall the amount that you milled on the head to achieve the 80cc? Any special head gasket used?

Dusted off the Snap-on valve spring compressor. Installed the valves, springs, locks.

One thing to consider is that you will gain back a little of that lost compression from the over size on the bore. That may be why they dropped the top down to keep the compression stock. I don't have all the parameters to do the math on that engine.