Cooling issues

[Stacked440]

Info on car is : 440 Mag with a 3-core BB radiator with a new alum high volume water pump from 440 source and a new spring in the lower radiator hose.  The darn thing still runs hot on days like today at upper 80's low 90's.  Just below the "H" on the gauge.  someone tell me...what am I doing wrong?   Only thing I can think of now is new alum radiator and electric fans.

[74 340 4speed]

What temperature thermostat are you using, and more importantly, what kind is it?  I have found out that putting the expensive thermostats in my car saves me many down the road.  I use the Mr. Gasket 160* stats in my rides and they usually hover around 170-175*.  On days that are 100* or over, the cars usually max out at 190*.  If you don't have one at all, and its wide open, the radiator never gets a chance to cool the coolant down before it goes back into the motor.  How long does it take your car to get to H on the gauge? 

[cudabob496]

I have a 72 service manual for my Cuda. It lists possible causes of overheating: blocked radiator air passages, incorrect timing, low engine oil, incorrect valve timing, bad temp gauge, restricted overflow tube, faulty rad cap, frozen heat control valve, dragging brakes, excessive engine idle, frozen coolant, faulty fan drive, faulty temp sending unit, faulty vacuum bypass valve, overfilling, insufficient corrosion inhibiter, blown head gasket, broken or shifted lower hose spring, low coolant level, collapsed rad hose, fan belt lose, glazed, or oily, air leak through bottom hose, bad thermostat, water pump impeller broken or lose, restricted rad water passages or restricted engine water jacket.

[Chryco Psycho]

is the guage sender good ?

[ted]

exactly, unless its boiling over its not over heating.

[cudabob496]

Are you saying it's okay for a preformance engine to run at 220 to 230, as long as it is not boiling over!

[ntstlgl1970]

I think what others are trying to say is that the temperature needs to be verfied by something other than the (presumably) stock 30+ year old gauge and maybe sender before changing a bunch of parts.

When does it run this hot? All the time? Just idle? Only on the freeway?
What thermostat are you using, a Stant (sorta chrome looking) or Mr. Gasket (Robertshaw - brass with a "cup" on the bottom) style?
Can you verify the coolant temp with a known good mechanical gauge or infra red temp gun?
Does the car start pinging or detonating when it gets this hot?

[matt63]

A proper electric or mechanical temp gauge would be a good start.  To me, thermostats and rad caps don't make a difference if your cooling system doesn't have the capacity to remove enough heat from the system.  You need a good fan, rad and shroud.  I'm just dealing with a similar problem and it looks to be solved.  I threw away my 5 blade fan and went to a 7 blade.  It runs about an inch from the 22" 4 core rad.  I also added a shroud. My "plan B" was to go to an aluminum Flexalite dual fan unit for $800.

[cudabob496]

On my 496 Cuda I put in a $250 Howe aluminum radiator, and it rarely gets above 180 to 190. I only need to turn on the 14 inch electric fan 5% of the time. Don't even need a fan shroud like I used to have. I do have a vented hood which allows air to move more freely through the radiator, and I use a high flow thermostat. Also, I agree, a good autoguage mechanical temp guage is around $30 and screws right into the water pump housing. A simple mod.

[Stacked440]

It has a 160 Degree Thermostat in it, and the entire motor is new, nothing that I know of could be in the water passages as the block was boiled out and the heads are new.  If its 70 degrees out and I just cruise at 55 it runs just above halfway on the gauge.  But if it gets above 85 or so, it gets to hot to be comfortable to drive.  The gauge could be bad but it reads good half the time?Thing is just downright funky.

[black71]

what does the lower hose spring do?

[matt63]

It stops the hose from collapsing under low suction pressure when the pump is running at high speeds. 

[Chryco Psycho]

Generally an engine will run cooler with a 180 or 195 * T stat , the reason is once the engine gets to 160 the thermostat is reduced to being a flow restrictor , with a 180 or higher the thermostat should close & allow time for the water in the rad to cool more before re-entering the engine , check the timing , make sure you are at about 14* at idle & 36 at 3000 rpm this alone can cause overheating
 what size rad do you have in the car ?

[matt63]

... check the timing , make sure you are at about 14* at idle & 36 at 3000 rpm this alone can cause overheating
 what size rad do you have in the car ?

Does advancing the timing cause the engine to run cooler or hotter?  Mine runs nice at 18-20 degrees initial!

[Chryco Psycho]

Advancing causes the engine to run cooler