Sorry you are having trouble. You can get an inexpensive test kit for exhaust in the coolant at Harbor Freight. Charlie, a contributor on the old site, use to suggest taking the belt off and starting the engine and look for bubbles in the radiator. Could be air getting in around the water pump packing, a plugged radiator or engine coolant passages among other things like head gaskets. My 31 had a pin hole in the water pump casting that drove me crazy. What work has been done to the engine and rad? What coolant are you running? Is the baffle still behind the water pump?

Dave

@david-dunton I rebuilt the water pump because the impeller was toast.  I do not recall there being a baffle behind the water pump

it may have been there and you didn't notice. It would be right behind the impeller. https://store.fillingstation.com/detail/RW-182/Chevrolet_19291934_WATER_PUMP_BAFFLE_PLATEOD_234.html

@david-dunton I don't recall seeing that.  As rusted as the impeller was I am sure that baffle was log gone.  The car sat for over 32 years.  I will order that after I check for exhaust gas.  Right now I am running straight water since the coolant is on the street.

I have a picture of inside the head but can not post it here is there another way

What message are you getting when you try to post it here?

@tiny I am a new member and was not able to post pictures but I can now

@wayne-2 Just wanting to make sure. Thanks for the update.

If it sat for that long and you are just getting it going I would hope you did a complete cooling system flush. In addition to the suggestions above also be aware that incorrect timing can contribute to overheating. 

@david-dunton This is the inside of the block behind the water pump.  I think the baffle is the round part

@steve-d The head was rebuilt and I flushed the block.  I think it is timed correctly.  I was unable to find a picture of the timing mark on the flywheel and used what someone had painted silver

• I think many of the members here set the timing by ear. The original spec called for 12 degrees BTDC and with today's better gas most find that about 18 degrees works best. 

That looks like you are good on the baffle. Did you check the coolant for exhaust?  You will get it figured out. How much coolant are you putting in the rad, it should just cover the core when cold. Have you checked the packing nut on the water pump it should just be tight enough to allow a very slow drip to keep the shaft cool. 

Good luck, keep letting us know what's going on.

Another thought- I bought a inexpensive laser temp gauge that has really helped me in diagnosing cooling problems it may be something to consider.