4R RUSH

Well after driving my car on the freeway and home from work the temp gauge slowly moved up to around 225degrees. It has a wopping 80 miles on the car. This was alittle upsetting. I went ahead and added a bigger 14 inch fan to my Northern aluminum radiator and started the motor in the driveway and let it idle. The temp slowly climbs to the same even with a 2000 CFM fan. I then tried a 160degree thermo but it didnt really help. As I have been putting the coolant back and forth into the car and using a oil change pan(Wiped clean). I noticed last night that there was alittle oil residue but cant determine whether or not that was from my own doing or not. I will drain everything, flush with water and refill with new antifreeze. I will get a Infared temp gauge and measure to doublecheck that my after market gauge is correct but with the "meat" thermo from my kitchen it look pretty close.

It has a double row aluminum Nothern radiator that is supposed to be more efficient than stock and a aluminum fan should with a 14 inch fan.

I have checked timing, and it is set at 10 degrees advanced but at am a loss why it is running so hot. The block is bored .040 over and it has a edelbrock performer package with head, cam and intake. Not a real radical cam so I cant figure out what is the problem.

I would appreciate any input as the only thing that I can think to do now is to pull plugs and see if I can see anything odd. The motor runs fine otherwise. Any ideas???

scootchu

With the cap off and the engine warmed, do you see flow through the radiator?
Did they put the right water pump on the engine? Could be that it's not rotating the right direction. Sounds to me that something is blocking the water flow somewhere.

4R RUSH

I pulled the cap last night and I have an edelbrock high flow water pump. It is flowing just fine from the pass side across to the driver side under the cap area. After I flush I will be checking to make sure that all the air is out of the system again.

TexasAxMan

I thought .040 over was a no-no with these engines (assuming you have a 289 or 302). I could be mistaken. Make sure you are using a 50/50 mix of coolant and water.

Randys66gt

I know this is a dumb question but I did this, I forgot the fan shroud. I ran the same thing, rad, fan, w/p, t-stat and couldn't figure it out. Freeway was good at 160 but streets, it went bonkers. Shrouds do make a difference. Good luck!

urban_cowboy

A couple of things.

1. 14" is not a very big fan...I am running a 19" with a big block shroud. Air flow is a must.
2. Are you running a flex fan or clutch fan?
3. Air flow is a must...Are you running a shroud?
4. 160* thermostat is too low...180-190 is more right.
5. How is your AFR? Running lean can cause overheat issues
6. Air flow is a must...make sure if you have an A/C condenser, oil cooler, or tranny cooler that they are mounted parallel to the radiator (this was an issue with 69 and 70s).
7. Air flow is a must...how far is the fan from the radiator...you want it as close as you can without cutting the radiator (like 1-1.5" to allow for engine movement).

4R RUSH

I know the 160 thermo is too cold but I am still troubleshooting. I will install the 180 later. I do have a condenser but havent even run air yet. Timing and carb are not an issue and I do think that that the fan is maybe too small and will install a 16 inch Spal directly on the radiator as their is almost no clearance between the water pump and radiator. It should not matter on the freeway but it even gets to 225 degrees running down the road ( with a spring in the lower hose) The dog gone rad for a 65 is already too small but I have to live with that. I am wondering how many others are running with a 040 overbore or did I screw up going that far and not getting a new block.

Gun Jam

who says 225 is too hot....

Its up there Im sure you would like to see 212 but isnt 225 within tolerable upper limits? I would say it would be too hot at around 235 what do you guys think about that? What number can we agree that if it goes above its too hot?

-Gun

KMatch

Does the fan blow the right direction? Now that you're through snickering, hold a rag between the radiator and engine and see if the rag blows backwards or sucks into the fan. Been there, done that, argued until I proved myself wrong. At 30 mph the fan would cancel out the air forced in from the front. And yeah, you need a bigger fan, but you know that already.

Other than that, it sounds like a lack of coolant flow or faulty gauge. Does it ever boil? Are you seeing the flow when it's supposedly hot (you mentioned t flowing in a previous post)? If so, blame the gauge cuz at 225, you won't be looking down an open radiator long before dialing 911.

KMatch

Does the fan blow the right direction? Now that you're through snickering, hold a rag between the radiator and engine and see if the rag blows backwards or sucks into the fan. Been there, done that, argued until I proved myself wrong. At 30 mph the fan would cancel out the air forced in from the front. And yeah, you need a bigger fan, but you know that already.

Other than that, it sounds like a lack of coolant flow or faulty gauge. Does it ever boil? Are you seeing the flow when it's supposedly hot (you mentioned t flowing in a previous post)? If so, blame the gauge cuz at 225, you won't be looking down an open radiator long before dialing 911.