I recently rebuild a 70's 350 for my camaro, bored .30 over, flat top pistons, cam blablabla.. i kept the old worn out 882 heads and never bothered to check them for cracks since i was going to get aluminium heads anyways once i have the cash.

Anyway long story short, did the break in, drove the car around a couple times, went through about a tank of gas and suddently i started heating up.. i drove it home and realized the block heater plug blew out and lost all it coolling fluid..

Put a new one in, filled it up, start and runs fine but over heats slowly if im hard on the pedal. Could the heads have cracked ? the top rad hose does get hard so i guess thats not a good sign, could the block be cracked aswell ? its not burning oil and there is no oil in coolant or coolant in oil..

I will start by changing the thermostat, i was thinking maybe lean jetting would make it run hot or even a too small rad as it is the stock one..

Hope it is not the block! heads i was going to change anyways..

Any advice would be appreaciated

Thanks

 

Do u have any way to check air\fuel mixture? if so it wouldnt hurt to check for a lean condition. i would take the thermostat completely out and see if the problem persists.

 

I checked the plugs and they are on on light colored side so i guess its running a bit lean.. I am running a qjet on it for now i dont have any idea on the jetting.

I will try removing the thermostat and see what happens..

 

Fans coming on? Air dam and fan shroud intact? Timing not retarded? Radiator clean? Water pump working? Rad cap ok?

 

Yes fan is a clutch fan and its fine, the shroud is good also, i will check the timing again but isnt it too advance timing that will make it run hotter ? and im puzzeld about the pressurized top rad hose but i will try taking out the thermostat and see if anything changes.
thanks

 

No, excessive retarded timing will make it run hot.

Just try advancing it. Might even run better.

 

Just recently went thru the exercise of recurving my dist for max timimg across the rpm ramge. Got lower temps as a bonus.

 

Have you checked your thermostat? How about your water pump?