350 TBI overheating

[field57]

Means nothing by itself. Still within spec.


How do you know it's overheating? Temp gauge? Or by blowing coolant out of the radiator? Is the upper hose pressurized?


Temp gauge in the cluster, and I verified it with a mechanical aftermarket gauge and got the same readings.



It isn't possible for the upper rad hose to suck flat if the rad cap is working properly, UNLESS the overflow hose is plugged/restricted. Any vacuum in the cooling system is intended to be relieved by inflow of air (or coolant from the overflow tank, if equipped) through the overflow hose.

So you need to define "for a bit". One second? Ten seconds? Two minutes?

I tried 2 rad caps but I did not check the overflow line for blockages yet. I would say it went flat for about 10 seconds and then went back to normal as it was cooling down idling. The cooling system was under pressure 2 days later when I removed the temp sender to install the mechanical gauge. It popped right out of the head as I was unthreading it.