I saw some other posts on this but here is my solution for others. Engine only overheated after a couple of minutes at idle, not at full speed.
Temp was reading 140-160deg on heads using laser temp guage.
Changed water pump, poor condition but no better temp when finished.
Changed thermostats, gummed up with salt, replaced still no change in temp.
Changed poppet valve (water pressure relief valve) diaphragm also gummed up solid with salt, no difference.
Removed cylinder heads found waterways in heads bunged up with salt. Scraped out and poured on muriatic acid. Washed off and replaced, temp down to 105 deg. This engine had been in storage for three years. Obviously not flushed out before storage. The laser temp guage was the big help here. Also beforehand you could not hold your hand under the telltale stream it would burn your hand. Now I could hold it there all day.
Temp was reading 140-160deg on heads using laser temp guage.
Changed water pump, poor condition but no better temp when finished.
Changed thermostats, gummed up with salt, replaced still no change in temp.
Changed poppet valve (water pressure relief valve) diaphragm also gummed up solid with salt, no difference.
Removed cylinder heads found waterways in heads bunged up with salt. Scraped out and poured on muriatic acid. Washed off and replaced, temp down to 105 deg. This engine had been in storage for three years. Obviously not flushed out before storage. The laser temp guage was the big help here. Also beforehand you could not hold your hand under the telltale stream it would burn your hand. Now I could hold it there all day.
