After looking more closely at the deck of the block and considering the condition of the engine when I received it, I've come to the final conclusion to pull the block have it serviced.
Here's kind of a timeline that has lead to this conclusion.
1981- the engine was rebuilt.
Grandpa drove it up until about 2000. At that time I helped him replaced the exhaust manifold gasket.
2000-2017 It did not run or move.
When I got it running in 2017, the engine compression was blowing into the cooling system. I pull the head off and had it rebuilt. During this time, I noticed that exhaust manifold was very, very rusted. All of the mating surfaces were so pitted they were not functional. The Intake mounting studs were rusted almost all the way through and could not be removed. The intake warming flapper was also seized in place. I didn't think much of this until now. Keep in mind. The truck has spent it's whole life up here in Northern CA. We don't get a ton of rain and humidity is always very low. I was able to find a replacement out of New Jersey that was in much better condition.
So I installed the head and ran the truck again and I now have coolant leaking into the cylinders and out into the exhaust manifold again.
When I looked closely at the condition of the block deck, I have found some very deep scratches that lead from and to coolant ports and cylinders. I know for a fact that I did not create these when I removed or installed the head. They are deep enough that head gasket would not be capable of sealing, especially being the metal side of it and not the fiber side. I believe these were created when the engine was rebuilt in 81. Maybe it didn't leak coolant much at first, or it had gone unnoticed by my grandpa. But the condition of the exhaust manifold leads me to believe that this has been an ongoing issue. Take a look at the
photos. There is also some serious damage to two cylinder walls. I guess a complete overhaul was inevitable.
