The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Overheating issue

rich weyand · 06-03-2016, 11:02 AM

Check the instructions to see if those heads require an external bypass like the vortec heads do. Lack of a bypass (internal or external) will give that behavior. Some heads (like 882s) have them, some heads (like Vortecs) don't.

Do you have the heater hooked up? Do you have an on/off valve on the heater hoses? The heater core can act like an external bypass, but not if you have an on/off valve on it.

Which thermostat is in it? Stock is 195, but you could go to a 180.

06-03-2016, 11:02 AM	#3
rich weyand Registered User Join Date: Apr 2014 Location: Bloomington Indiana Posts: 1,041	Re: Overheating issue - I am stumped! Check the instructions to see if those heads require an external bypass like the vortec heads do. Lack of a bypass (internal or external) will give that behavior. Some heads (like 882s) have them, some heads (like Vortecs) don't. Do you have the heater hooked up? Do you have an on/off valve on the heater hoses? The heater core can act like an external bypass, but not if you have an on/off valve on it. Which thermostat is in it? Stock is 195, but you could go to a 180. __________________ Rich Weyand 1978 K10 RCSB DD.