I have been over heating reciently in which has never happened before. I just changed the manifolds and when I did I poured out a ton of sand. I think some sand is in the block so I am going to flush it out. I don't run a termostat and have never run hotter than 120 degrees in the past. I am thinking of droping in a 160 temostat after flushing the block to slow the flow of water to pick up more heat. Any other suggestions as things to look for?
Pull all your cooling lines off and look for corrosion. Look at all the openings into your block and intake manifold. Inspect your lines and fittings. I have seen every part I have mentioned so caked with mineral deposits, that NO water could flow through.