Hey guys, Got a couple quick questions.
After 3 months Finally got the car driveable. Installed a remaned 302 and new hi-flow water pump, and 3 row champion radiator. Ran the car a few times in the garage and it runs right at 185 with the car at idle. My wife and I drove the car maybe 3 miles around the neighborhood because we still dont have a tag on the car. The engine started to get in the hot zone and come back down. It did it a few times but always came down. We put it in the garage and i checked to see how much coolant came out. I lost maybe over a quart in that little drive. I topped he of and let it idle maybe for 5 min. Right at 185 and no leaks from the cap. I installed a coolant filter. Its clear so I can see the coolant coming back into the radiator. I get random bubbles coming up. How long does it take to loose all the bubbles after filling the coolant system? And also I placed a pressure pump on the radiator. I thought maybe a bad head gasket already? But as I rev the engine the pressure in the radiator drops but when I let it come back down to idle the pressure rapidly builds. What gives?

Also, What is the max operating temp of that engine?

 

You can take one of the plugs out of the upper intake area to let some of the air out when it's cooled down or pull the hose from the outlet to the heater core, try to pick the highest point which is where the trapped air will end up with the motor off.

What Tstat are you using?

Does the lower rad. hose have a spring in it to avoid collapse at driving speeds? (won't happen at idle or revving)

Do you have a fan shroud, solid fan/ flex fan/ clutch fan? what type of setup?
What's your AF mix?

What's your timing set at? it can affect temps also.

A pic of the engine bay from the side & front may help to spot any obvious issues.

Most engines run at 190* -210* IIRC in reading the manual. You can get an IR temp probe at Harbour Freight for <$20 and check temps around the engine. The stock gauge isn't very reliable or accurate normally.

Jon

 

If you use the genuine Ford thermostat, it has an air vent at the top to let the air out when you fill with coolant, results in almost no air in the engine before you even start it up.

 

Hey Jon,
I am using a 185 degree thermostat.
I did reuse the lower radiator spring even though I was told using good year miller hoses dont require it.
I dont have a fan shroud. I replace the radiator with a 3 row radiator that came with a 16 inch electric fan.
The air fuel mix I checked it before installing dual exhaust. It was at a 14:1.That was at idle. I never had the oppertunity to drive with the sensor connected.
I cant remember what the timing was but i didnt deviate from the manual. I would like to say it was at 6.
I do have a temp probe. Like I said it was running about 185 when it was in the garage. I didnt think to check it when I came home though.

 

I think I see your problem, your engine is Chebby orange

Ok, any idea if the Tstat is oritented as 2+2GT shows above? if your still getting air then there is probably still air in the system which expands and heats up.

The AF I meant was antifreeze, sorry should have typed it out.

Any idea what CFM that electric fan moves? who made it or the amps it pulls? I've read that some companies overrate their CFM and don't move as much air as claimed. I would guess your missing out on ~20% of your cooling area with the corners outside the shroud area.

Depending on the amps the fan pulls you may need to upgrade the alt., it looks like the stock 42A-66A one which may not be able to keep up with the draw of the fan when it kicks on. Is the fan constant or on a temp switch relay and can you verify it's running when needed while you drive? You could temp. run a light to the inside the car wired inline with the fan so that when the fan has power the light comes on to let you know it's working.

Whenever the AC kicks on it'll also increase the strain on the alt. to keep up. If you have any other extra electrical stuff like headlights being on (big draw), stereo, amps, etc. that will add to it.

Jon

 

Hey, it matches the paint Job Orange car blue engine just hurts my eyes.
I think the fan supposedly pushes 1600 cfm i think.
Its always on. It draw about 12 amps at full load. The inrush on the fan I think was about a 100 amps. The tsat did have that venting pin hole.

 

Then why the blue hoses? Thank goodness the car isn't Grabber Green.

I have a yellow car with a red engine in the garage. Seems to work.

The engine should have a 190° thermostat, that was where it was designed for best power and efficiency. 220° is the overheat threshold. The 68-up DVCV was set to start cooling the engine at 220.

 

I did a lot of shopping to find the biggest CFM fan that was thin enough to fit (for Jim's 408 powered 66), I ended up with a 3,200 CFM unit that looks about the same as yours.

In any case, due to the size of the radiator opening, the cooling system on early Mustangs is marginal at best. It is just a matter of chipping away at the weak points.

Still, in traffic on a good hot desert day, the 66 will touch the edge of 220.

My younger son used a 3 row Champion radiator with a FLEX FAN in his 302 powered Falcon, it never gets close to hot.

 

I dont think goodyear makes the hi miller hoses black. If not I would have gotten it. I actually was about to paint the engine a semi gloss black but decided the brighter orange color would help find leaks and help problems stand out. Ever been on a good size yacht? 99 percent of the engines are a super white color. A leak is spotted instantly.

If I keep having problems I will switch to a 195 degree tstat.

 

Do you have a 3 row rad also? So your tapping 220 on hot days? How much coolant is normally missing from your radiator?

Anybody running a coolant overflow tank?