You noted that you have an electric fan. What temperature is that fan set to come on? Also is that fan big enough for your radiator? Also are you running a mechanical water pump or an electric? It would also be nice to know what motor you are running.

 

My fan is on all of the time. I'm not sure what CFM the fan is. I am running a 350 engine with a mechanical water pump.

 

You said it is running 220 on a hot day. Is it idling or at higher RPM? Not always, but a lot of times, if it is overheating at higher RPM, then you maybe dealing with the lean mixture issue. Overheating on idle/low speed relates to the circulation/cooling area issue.

BTW, Here is a copy of the edelbrock owner's guide.

Owner's manual

If your numbers were ground off, then the only way to tell the carb size is to pull the main jets and the metering rod and compare it to the chart.

I would go about it in the following steps.

1. Change the thermostat back to about 180. Install it the correct direction.
2. Check the size of the fan. It should pretty much cover the radiator at least in one direction. If you have a shroud, then the fan should be set away from the radiator and the shroud should funnel the air to the fan. Although not optimal, if you don't have a shroud, then just place the fan on the surface of the radiator.
3. Check the temp. If it is overheating at idle/slow speed, then I would suspect the water pump giving out. Also I have seen cases where the radiator hoses buckle. Check that too. If it overheats only at higher speed only, then I would suspect the lean mixture.

Thermostat is designed to keep the motor at certain temperature. If stuck open, it will cool the motor which it is not efficient. If it is stuck closed, then obviously you will have an overheating issue.

As for the comment about coolant needing enough time in the radiator to cool, I claim BS. Cooling system is a thermodynamic system. As long as there is a continuous run for the coolant to travel, (as in no blockage) faster moving coolant will cool the system faster than a slow moving coolant. Why do you think that they make high performance water pump with higher flow?

Sounds like you have a super duper radiator. So I wouldn't worry about that. Also you may want to think about installing a fan control switch. There are various options that give you control over when to kick in. Obviously it wouldn't do anything for your cooling issue, but it is more efficient with the fan control than to run the fan all day long.

 

Gasser,why do you think it is more efficient to not run the fan all the time? Are you concerned with the need for the alternator to make electricity continuely? If so, I think that is a small price to pay to be sure that your fan is functional before you leave the house and then overheat two miles down the road. For a critical system like the electric fan, I like the reassurance of hearing the fan come on when I first turn the key to be sure that no fuse or wiring issues exist. My buddy had a smoked wire and got stranded about three miles from his house when the temp gauge peaked and the rad went peepee all over the pavement. JMHO, Jag

 

Yeah I agree with your comment, but I am also one of those guys who is **** about being efficient. As I said on the post, "it would not do anything to solve his issue." But generally speaking, you don't need electric fan running all the time.