The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 71 350 running hot coolant backup up problem

OBS454 · 01-13-2018, 02:16 PM

Can't see clearly but as another mentioned check the gaps between the radiator and shroud (only effective at lower speeds and idle) so that the air drawn is through the core. I remember someone telling me that those carbs are notorious for being jetted rich out of the box and that many people change the jets before even installing - maybe someone went too lean? (I run Q-jets so don't have much experience with those) Have you read the spark plugs after a run? BTW you should connect the PCV valve if you're already driving it around. Using an IR gun on the location of the temp probe would be another piece of useful information.

01-13-2018, 02:16 PM	#59
OBS454 Registered User Join Date: Aug 2014 Location: Dallas, Texas Posts: 54	Re: 71 350 running hot coolant backup up problem Can't see clearly but as another mentioned check the gaps between the radiator and shroud (only effective at lower speeds and idle) so that the air drawn is through the core. I remember someone telling me that those carbs are notorious for being jetted rich out of the box and that many people change the jets before even installing - maybe someone went too lean? (I run Q-jets so don't have much experience with those) Have you read the spark plugs after a run? BTW you should connect the PCV valve if you're already driving it around. Using an IR gun on the location of the temp probe would be another piece of useful information.