Small Block & Big Block Chevy Specific - 400 sbc running very hot-PLEASE HELP

I just rebuilt a 400 small block chevy engine with new edlebrock heads, primed the oil pump before starting (65 PSI) filled it with water.
Start the engine and the water temp. goes to 210 degrees, I believe it has air in the system. I pulled the plugs and aired up the cylinders , no bubbles in the radiator and the compression is 150 across the board.
How can I get the air out of the cooling system? I don't know what else to do and I'm starting to get real pi$$ed off.
PLEASE give me some ideas because I'm lost.
Thanks for your time :bang:

Well Since you provided very few details its hard to make a judgement call

Did you drill the steam holes in the heads

Did you drill the steam holes in the heads

yes, they have been drilled.

What other info should I give for more ideas on this problem?

thermostat might not be working! Put it in some boiling water in a pot on the stove and make sure its opening up at the temp. that its set for. Ive had 3 brand new thermos not work causing the same problems

edit:
and also, it may sound silly but make sure its facing the right way on the intake. Little mistakes can happen

Kind of car type of radiator sizes pictures right water pump thermostat rating etc etc details about motor....

What kind of fan are you using? How bout a fan shroud? Need more details to help you out...

toss the thermostat. get the washer kit from moroso or equivelant. i put in the medium blue washer for my vortec headed 406. the washer will basically eliminate air bubbles.

had mine at 2500 rpm with a 14" unshrouded permacool fan, a 60 dollar duralast water pump, and an aluminum radiator for about 25 minutes and it didnt get over 165.

a shround can definetally help out depending on the application. so those are two things i would consider. a shroud/fan, and a washer

JMO! good luck

1.Does it have a good fan and a shroud?

2.What's the thermostat temp, and have you made sure it works properly?

3.What kind of water pump?

4.Any Antifreeze?

5.What Radiator, and how many cores is it?

6.What makes you think it has air in the cooling system?

7.Have you driven at 50+ and if so what was the temp?


I just got my car "operational", it runs at 190 (190 T-stat) on highway but creeps up to 230 because I have no shroud yet.

First, I Need a shroud, but later I plan on an IC sprayer contolled by a speed/temp switch to turn on only under 15mph and above 215 deg.

1.Does it have a good fan and a shroud?

2.What's the thermostat temp, and have you made sure it works properly?

3.What kind of water pump?

4.Any Antifreeze?

5.What Radiator, and how many cores is it?

6.What makes you think it has air in the cooling system?

7.Have you driven at 50+ and if so what was the temp?


I just got my car "operational", it runs at 190 (190 T-stat) on highway but creeps up to 230 because I have no shroud yet.

First, I Need a shroud, but later I plan on an IC sprayer contolled by a speed/temp switch to turn on only under 15mph and above 215 deg.

Its a 32 ford with a 400 sbc, mild cam,180 thermostat, new water pump.
A 4 core aluminum radiator and a 15 inch fan(not electric).
I dont have a fan shroud because it does'nt have a hood, if I put a shroud on it WILL like like sh$@ and I dont want that. I tested the thermostat in hot water and it opens good.

if you still think there is air in the system then jack up the vehicle one corner at a time to move things around. that still might not get it witht he thermostat holding things in place.

thats about the only thing i can think of? and possibly the washer idea.

also, do you have cooling deck plugs in the block? if so, the center coolant holes in the gasket might not be big enough? i had plugs in mine and i had to drill another 1/8th inch hole between the two center ones already there. just another thought

this may sound stupid but was you block sonic tested and how thin are you cylinder walls. i have seen 400 blocks have such bad core shift that when bored and honed .030" over, the cylinder walls were only .085"-.100" thick.

this may sound stupid but was you block sonic tested and how thin are you cylinder walls. i have seen 400 blocks have such bad core shift that when bored and honed .030" over, the cylinder walls were only .085"-.100" thick.

the bore is stock, the cylinders were just honed to clean them up.

whats your timing set at?

Without a fan shroud its going to run hot at low speeds. Since you are dead set against the fan shroud then get an electric fan and shroud combo.

whats your timing set at?
x2 whats your timing set at, is the balancer timed correctly also?

Are you running a serpentine accessory drive? If so, are you using the proper reverse rotation water pump? Are you running a reverse rotation pump without a serpentine drive? Just something to check.