radiator configuration
 

Radiator help please. I just pulled a blown engine out of my 86 pickup. I replaced it with a 350 out of a 71 gmc. everything worked fine (I removed all the crap) till I started it up. It over heats. I have one of the heater hoses running to the intake manifold, one to the radiator (that was the configuration on the 86) Now, no matter how hot it gets, the thermostat wont open. I have good circulation in the radiator but I wonder if the configuration is not letting pressure build behind the thermostat? Upper radiator hose never gets hot. Ive tried two new thermostats.

Thanks for the help

Those two on the deck.....thier no help. and the last pic is the engine Ive replaced. The boys said..."Dad, the engine light came on?"

Re: radiator configuration
 

Same setup as mine. It seems to me you need to check your thermostat.

Re: radiator configuration
 

Try drilling a 1/8 hole in your thermostat;if an air bubble forms below the thermostat it wil not open

Re: radiator configuration
 

could you have an issue with the block you installed... try leaving the thermostat out and see if it overheats

Re: radiator configuration
 

Also....did you change the intake manifold ....if you put the intake gaskets on backward it will block the coolant to the thermostat