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Cooling system trouble in Arizona

I have just spent the last 6 months rebuilding my 1980 Ranger XLT Lariat. Everything that I am doing is being done the right way, almost with all new parts. It had a 351m 2 barrell that made approx. 130 hp new out of the factory and I turned it into a 406 Stroker, bored .20 over with a Edelbrock EGR Performer Intake, Edelbrock 1406 EGR 600 CFM 4 barrell, 400 crankshaft, TMeyer KB2347 pistons, Comp Cams 255deh Rv cam and valve train. 9.3:1 compression so I can still run pump gas. Should be around 325 hp and 450 ft lb torque. Really runs awesome.
The cab and interior are complete now and I have installed all new A/C components with the exception of the condenser (which I flushed out thoroughly) and the original liquid line between the accumulator and condenser.
Even with our 114 degree weather we have been having, I can let the truck idle all day long without the Air turned on and the temp gauge stays right in the middle. Just had the a/c charged at work using a RobinAir machine. Now the air is awesome but as soon as I turn the air on, it instantly gets hot, even moving down the road, turn it off and right back down to normal. I was thinking maybe my fan clutch was not working properly but visually seems to be fine and instantly stops turning as soon as engine is turned off. I realize a lot of air has to be pulled thru the condenser. Could it be that the original fan blade and clutch are just not pulling enough air? Thermostat not working correctly? Any suggestions? And moving away from Arizona is not an option
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Rooster Snorkler
Do you still have your fan shroud?

If you remove those often times they will just circulate air all around in the motor and not actually pull through the rad.

With all those mods and higher compression you may need to step into some electric to keep her cool.

My question is. Does it still get hot cruising at speeds or is this only at idle? If only at idle I recommend a fab upgrade. If it's all the time...then maybe you have other issues.

Also. Have you checked your ignition timing to ensure you aren't too advanced

What color are you spark plugs, Are you a little lean?

Automatic or manual Trans? Of automatic is the cooler still going through the radiator?


Rooster Snorkler
Another thing to check....

I wonder if it's your gauge. I've seen them where they will peg out. Like maybe you have a bad ground somewhere in the ac system and when you turn it on it pegs out your gauges.

You said it's instantly. How instant. Like 10 seconds or 3 or 4 minutes? Thsee gauges don't move real fast so if it pegs it will take a few seconds to climb up. If it takes minutes then I'd definately say you have a motor getting hot.

Also. Do you happen to have one of those infrared temp sensors? Aim it at the radiator and flip on the ac. See if there's really any change at all.
Sorry for not responding right away, but you were right on with the bad ground issue. Added new grounds all over the place but the main issue was the body to frame ground. Hope this helps someone in the future. I ended up adding a direct ground lead from the battery to the dash subframe and presto' everything started working right. Thanks for your help again.


don't play well w others
Fan shroud, and multi blade fan, and hope for the best, but I can tell you from experience when I built my 94, it ran hot with the A/C on. you will have to go with the electric fans. I used this, and they do a great job!

I welded some nut certs up to fit in the core support, and used 1/4" all thread to mount it instead of zip tie through the radiator

Make sure to plate your pulley when you take the fan off, the fan keeps it solid, and the belt will jump off without it being plated.
Found that out the hard way

You can get a controller for the fans from Jegs

This allows you to adjust when the fan comes on
It also turns on the fans when the A/C is turned on
I later put a switch on this feature for winter, it kept the temps too cold when the defrost was on
I used a mega fuse to control the whole thing

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