Hot engine after rebuild

Not true!
that was my experience. i pulled up to a stop light and noticed the temp gauge shoot up. pulled away on to a highway ramp, drove down the turnpike and the temp gauge went to normal. got off the highway, stopped at the bottom of the ramp, back up. checked under the hood, no belt. fired that mother up, boogied home. so long as i kept it moving, no problem. solid mount 8 blade fan with 3 core a/c radiator and fan shroud. don't believe it? couldn't care less. all that matters is that i made it home okay.
 
Basically, thermostat temps at the t/stat housing, upper radiator hose, and engine block. Possibly similar at the lower hose and water pump housing. The heat gun is also handy to see which parts, if not all, of the radiator core are hot, too. The exhaust manifold runners will be over 500 degrees F, so the area on the cyl head might have some bleed-over from the exh flow, as the inside of the head would not. Similar with the exh heat in the head crossover under the plenum area of the intake manifold.
As always, your posts provoke thought and accurate data! You've reminded folks of one of the FEW disadvantages of a dry intake manifold.
 
that was my experience. i pulled up to a stop light and noticed the temp gauge shoot up. pulled away on to a highway ramp, drove down the turnpike and the temp gauge went to normal. got off the highway, stopped at the bottom of the ramp, back up. checked under the hood, no belt. fired that mother up, boogied home. so long as i kept it moving, no problem. solid mount 8 blade fan with 3 core a/c radiator and fan shroud. don't believe it? couldn't care less. all that matters is that i made it home okay.
Key thing . . . direct drive fan. A clutch fan would have just spun and probably would have not tried to turn the water pump.
 
that was my experience. i pulled up to a stop light and noticed the temp gauge shoot up. pulled away on to a highway ramp, drove down the turnpike and the temp gauge went to normal. got off the highway, stopped at the bottom of the ramp, back up. checked under the hood, no belt. fired that mother up, boogied home. so long as i kept it moving, no problem. solid mount 8 blade fan with 3 core a/c radiator and fan shroud. don't believe it? couldn't care less. all that matters is that i made it home okay.

I believe you! In fact, even with good quality fans, thermostat, radiator and coolant, I still see the same sort of temperature fluctuation, to a lesser range to be sure, but present. So, having also driven plenty defective machines, with sundry defects, I too have had the experience of guzzling sundry coolants en route to the nest of the day. "Been Dazed and Confused for so long it's not true....."
 
I would have maybe run it no thermostat that way theres no bubbles trapped (too late now). Its gonna run hot being a tight motor but ya too advanced or a clogged radiator could be a possibility.
bad fan clutch. not sure what you got there.

make sure the thermostat isnt upside down, it happens and drill a 1/8 inch hole in it so air can escape.
I would run 185
 
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I believe you!
thank you.
A clutch fan would have just spun and probably would have not tried to turn the water pump.
took a moment to figure out why it stayed cool for so long up to that stop light. oh yeah, fan turns pump. eight blade fan (edit: went out and counted, seven blade) helped catch the air.
 
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Removing the thermostat can lead to puking coolant. There are two types of pressure in a cooling system. First is static pressure. Static pressure is produced by the thermal expansion of the coolant as the engine warms up. Second is dynamic pressure, produced by the pump when the flow meets a restriction. The designed restruction is the thermostat. When the stat is removed, the restriction is the radiator and this is beyond the rad cap. This exposes the cap to the total of the static and dynamic pressures. If this total exceedes the setting of the rad cap, coolant will be expelled. This can occurr at normal operating temperatures.
Just something an "old guy" explained to me! Lindsay
 
Make sure the belt is good and not slipping My old farm tractor John Deere LA has no water pump or thermostat just a big radiator and fan thats the way they came from the factory work it hard and never overheats
 
Try setting timing with vac adv plugged to 15 or more deg at idle. When I start a new motor, first thing I do is set curb idle to 2,000 rpm and then adjust timing. As long as there is not so much timing that there is cranking resistance at start, more timing is better for the motor while it is sitting in neutral with no load on the motor during break-in. Retarded timing makes undue heat.
 
Question: did you confirm the timing mark on the damper?
Maybe advance it 5° more to see if it runs cooler or starts pinging, needless to say, if it is pinging, put it back ASAP.
make sure you are setting the initial timing with the motor at idle < 800 RPM.
My $.02
 
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