68 Dodge 440 overheating-not water pump

[sixpack_sid]

I have a 68 Dodge Charger I just finished restoring. It has a 440 engine from a 77 Chrysler New Yorker. It has an original water pump and an aftermarket aluminum 4 row radiator from Champion. I have a stock fan on it but there is no fan clutch or shroud. I am having overheating issues with it. I filled up the radiator and made sure there was enough fluid in it. After driving about 15 minutes, the temp gauge read 240 and was climbing. I pulled it into my garage and shut off the engine. I could hear the antifreeze boiling in the radiator. After a couple minutes, I saw the fluid flow back into the overflow tank and the tank eventually spilled over to the overflow tube and out onto the ground. The fluid was brown. It took over 2 hrs to cool down.
I was wondering if I need to make a shroud to fit over the fan, or if I should mount an electric fan on the other side of the radiator. Or does anyone have any other suggestions to fix the problem?
Sid

[Chryco Psycho]

If the fluid is brown I would flush the cooling system first , if the rad is plugged you will not run cool .
When is it heating up , sitting in traffic or running down the freeway ? if it is sitting in traffic you need more fan so  a jaguar clutch & Flex-a-lite 18 " 6 blade fan would be the next thing to look at .
If it is heating on the freeway you need more air flow , a fixed fan can block air flow so a clutch may still help you
Tuning can have a lot to do with heat as well , retarded timing , or running too lean will create more heat .

[charger Downunder]

have you got a spring in the bottom hose to stop it from collapsing.

[Cooter]

Most likely will need to knock out a couple "freeze plugs", and flush out cooling system with a high pressure washer. Once you see what I'm referring to, you'll understand. Good luck, and BTW, that brand new radiator you just bought will need flushing out as well.

[Back N Black]

Did you burp the system when you filled the coolant, maybe there is air trapped in the system. 

[resq302]

Did you burp the system when you filled the coolant, maybe there is air trapped in the system. 

I agree.  I had that issue happen to me too.  One way to help resolve any issue with this is to drill a 1/16" hole in the thermostat to allow any air to be forced up through there.

[sixpack_sid]

I took out the t stat and tested it in boiling water. It works like it should. I also flushed the motor and rad it wasn't as bad as
I thought. The bottom hose has a spring in it but the top doesn't is it supposed to? I also got some coolant on the paint. I hope it doesn't harm the paint I hosed it off as soon as I noticed it. It got dark out so I will drill the hole in the stat tommarrow. Please keep the advice coming.
Thanks
Sid

[firefighter3931]

Sid,

(1) when the stat opened in the boiling water did you take a temperature reading ?

(2) With the cap off the rad ; does the coolant circulate well once the thermostat opens ?

(3) have you checked the ignition timing and verified that the carb floats aren't set too low ?


- the stat has to fully open at 180-185*
- coolant has to propely circulate ; if it moves too slowly you will overheat !
- retarded timing and a lean fuel mixture will cause excessive temps/overheating


Ron

[sixpack_sid]

Sid,

(1) when the stat opened in the boiling water did you take a temperature reading ?

(2) With the cap off the rad ; does the coolant circulate well once the thermostat opens ?

(3) have you checked the ignition timing and verified that the carb floats aren't set too low ?


- the stat has to fully open at 180-185*
- coolant has to propely circulate ; if it moves too slowly you will overheat !
- retarded timing and a lean fuel mixture will cause excessive temps/overheating


Ron

1) I asked for an OEM stat at NAPA and they gave me a 195. I pulled the stat out of the car and that is a 195 also. They both open in the boiling water test. Should I return the 195 and get a 180 stat instead? Or should I drill a hole in the 195? Where is the hole drilled-in the base or the part that opens?
2) I cannot check the circulation as this is an aftermarket Champion rad with the cap in the middle, not on the side.
3) It is on timing. What do you mean by "carb floats"?

I have headers on it, so there is A LOT of heat in the engine bay. Would that cause part of the problem?
Thanks for the replies.

[firefighter3931]

Sid,

- definately run a 180* stat and check to make sure it opens fully at the proper temp....you can use a heat thermometer to verify. If the stat doesn't open fully until after the water is boiling then that's a problem 

-once you get ready to fire it back up leave the rad cap off and watch the coolant. Once the stat opens it will begin to circulate. Blip the throttle and you should see the coolant begin to speed up.

- get the front end up on a set of car ramps when you fire it up with the cap off. This will push any trapped air out of the cooling system (burping)

- make sure it has enough idle timing...ideally you should have at least 12-15*@ idle. Carburators have a float adjustment. If the float is set too low you will not get enough gas and the mixture will be lean and the engine will run very hot 


Ron

[sixpack_sid]

I got a 160 Superstat from Napa and installed it. She runs a lot cooler now. I took her out for a test drive today and she didn't go above 180 until I was sitting at a stop-then the temp went to 200. I hope it will be ok now.
Thanks for the replies!!

[tccjj49]

Looks like the guys got you covered on most of it.I had that problem to and it was my raditor cap,looked new but didnt release at the right temp and pressure,so it got hotter and more pressure untill it popped to tank.check if right cap and working,they have testers or just get another new one and hope.

[sixpack_sid]

Looks like the guys got you covered on most of it.I had that problem to and it was my raditor cap,looked new but didnt release at the right temp and pressure,so it got hotter and more pressure untill it popped to tank.check if right cap and working,they have testers or just get another new one and hope.

Thanks for the advice! I plan to take the car out this weekend for a long drive. If I have any problems (I hope not!) I'll check that out. 

[Paul G]

You stated you do not have a fan shroud. That is a very important part of the cooling system, really comes in to play at idle and in slow traffic. You really should get one. And, if you use the car in cooler weather that 160 stat is going to be too cold. Engine wont heat up properly, and poor heat inside the car. I ran a 160 for a while, worked fine in the Phoenix summers. When in cooler weather it was just too cold. Switched to a 180 and drilled a bypass hole.