krobillard

I know this is a big topic of mustangers, here's the problem. 1965 Mustang coupe.
New Engine- 302 bored.40over, 289 heads / 4 barrel/ headers/ auto trans-rebuilt
New Orginial raditor ( small ), and orginial 4 blade fan .
I'm the guy who had his thermostat backwards, and drove it for about 1 hour.
The Problem -- replaced the thermostat, the temp during idle seemed ok, it never got to hot.
I drove it last night and the temp guage was very close to H, got worried and drove it home.
I have not bought a mechanical tempguage or themroguage for the raditor yet.
Do you think I warp the heads? or is the raditor and fan to samll for the engine?
Is there a way to see if the heads are warped?
Thanks

dnswwood

First thing I'd do is get a manual temp guage and see what temp exactly you are running. Its hard to tell just how hot you are getting on a C/H type guage.Get one you can read numbers onand see how hot you are really running.

dozierstang

Check your oil, if it looks like chocolate milk then the heads were warped. I doubt you did that but sounds like you need a biggerradiator. You can splurg and get an all aluminum or just get a larger one say for big blocks. 3 row I think. Then you can go with an electric fan setup or just get a higher flow 5 blade flex fan. If you don't have a high output alt then the electric setup will be expensive along with extra wiring relays etc.

Starfury

You should definitely have a 3-row radiator, especially with a .040" over block. A clutch fan (not a noisy flex fan) and fan shroud would be good ideas as well. This should be enough to get everything cooled properly.

That said, you still need to get a mechanical gauge to see exactly how hot 'hot' is.

krobillard

Thanks, the oil still looks brand new ( very clear looking), I did check that.
Next purchases are;
Mechanical temp guage, new flex fan (5-6 blades) and larger raditor.

bebo

It tries to overheat and it has a three core aluminum radiator and an electric fan. Seems like if I jump the fan controls and start the fan when the engine is started it warms-up and stays cool. If I wait until the fan switches on at the appropriate temperature the engine continues to gradually heat-up. It seems as if the fan can prevent higher temps but cannot reduce high temps. The fan switch looks like the temperature sending unit and is activated by water temperature. The fan sensor switch came with the fan from Summit Racing a couple years ago. The car is just now being brought to life so there is no other history with the fan. Does anyone know if there are fan switches as I described but with a lower temperature activation trigger?

Gun Jam

do yourself a favor and dont get a flex fan.

Look into an electric fan or a clutch fan as suggested to go with a nice Al radiator. cooling systems are important don't cut corners.

-Gun

barnett468

exactly how hot does it run at 50 mph or higher on flat ground?

what is yoiur thermostat rating?

what is your anti freeze ratio?

is your radiator chinese?

does your fan shroud cover the entire radiator?


your fan likely blows too little air and your rad is likely too small.

.

bebo

Thanks for the response. The car has a 3-core aluminum radiator, the fan covers the entire radiator, the radiator was made in the USA, the coolant is a 60/40 mixture of green antifreeze/water.
We are going to wire the fan direct to come on when the ignition is turned on and we'll call that good for now. The car is in Alaska and will only be driven in the summer so there is no hurry to have the coolant temperature increase to use the heater although it does get warm but just a little slower when the fan starts with engine start.

Starfury

Not sure why we're resurrecting a thread from '07, but...

I'm with Barnett here. Sounds like your fan is underpowered, or your cooling system is inadequate. A larger fan (1500+ CFM; Mark VII and Taurus fans are popular junkyard finds) and an adjustable temperature thermostatic fan switch (you should be able to pick up a Hayden unit from any chain parts store) might be good ideas. Or just get a clutch fan and be done with it. My clutch fan keeps my 331 cool in 110F heat.

There is no reason to run a thermostat colder than 180 if your cooling system is up to snuff. I don't even recommend that low. These motors are designed to run at ~210F, and a 192/195 thermostat will do just that. The thermostat should be setting the lower limit on coolant temps, not the upper limit.

If you're running that strong of a coolant mix, some Water Wetter would be a good idea. High coolant mix ratios result in increased surface tension, which results in decreased cooling capacity. Water wetter will help reduce surface tension and improve cooling. It's not a fix in and of itself, but I think it might be a good idea in this case.

I'm not a fan of the cheap 3-row aluminum radiators out there. They're gimmicks. A quality 2-row aluminum radiator with 1" tubes has greater cooling capacity than a cheap 3-row with smaller tubes. That said, I want to know what temperatures you're seeing before changing the radiator.