[herdfan75]

I have a 64 1/2 coupe with a 289. The radiator will take spells burping the water out of the overflow...so much sometimes that when you take the cap off you can't see the water level in the top of the tank. But, it doesn't do it all the time. I've tried 4 different 180 degree thermostats, new bypass hose...even a new three row radiator and two different new caps! It doesn't overheat and the heater works great. (The past couple of weeks here in WV have been 95 plus...while sitting in traffic the temp guage goes over about three quarter...it usually runs on the first line and only moves no more than half way...but this is the hottes weather we've had in the two years I've owned it.) I have a three core radiator with a six blade fan...any ideas?

 

[wayne50f1]

ive been playin around with mine, new 3 row , thermostat 180,
new hoses new radiator cap 13lb...no change...
finally got one of the overflow tanks that feed from the bottom, filled radiator to the top, put some water in the tank, runs cooler now, no more overflow spills
the tank did more to help than anything else ive tryed, it'll push water into the tank then suck it back out as it cools.
with the tank you can run the radiator full to the top, mine used to run couple inches below top, so ive added about a quart and a half or more fluid than before...keep watchin the overflow tank , you may need to keep adding to the fluid in it, till it finds its own level, dont open the radiator cap , just keep adding to the overflow tank.
if all else is ok with the car this will help,and its cheap to try, unless you want one of the fancy stainless tanks, that happen to be pretty trick looking like mine.

 

[herdfan75]

I've seen a pic of the stainless tank in another post. Do you know of any cheaper that would look good also? I know the autoparts stores have them, but they are kind of big. I may just try the stainless...it's really nice for the money.

 

[beechkid]

Although this will probably have no effect, try a 165 thermostat, that's the OEM spec.

Assuming that everything is functionally ok, here's some thoughts

1. If the water pump has been replaced in the last 10 years, it's a "high flow" type, these cooling systems were never designed for that flow level and can cause the radiator cap to "Lift" allowing fluid to escape.

2. Install a name brand radiator cap without the lever vent in it.....they are infamous for helping this to occurr.

3. Install a larger overflow container- when the heat level gets that high, they will dump up to a quart of fluid out.

4. The 3 core radiator is more than adequate, at the 3/4 mark, it is probably running a little warm but you will need to check the actual coolant temp at the radiator to verify the actual temp.

5. If you are running a clutch fan, make sure it's ok....should be plently of resistance, if not, replace- thats at least a contributor to the problem

6. Check the fan blade clearance to the radiator......1/2" is ideal, over 1" your loooooosing air flow.

7. Try installing a real good fan shroud...the OEM unit is really almost worthless.

8. Try richening up the fuel mixture just a slight tad, that will help it run a little cooler

9. retard the ignition timing by 1 or 2 degrees, that will help it run cooler.

DON'T do 8 & 9 until you have tried everything else, then do 8 first, try it, then if that doesn't work, try 9.

 

[beechkid]

Hotrod. or Rodworks.com has the SS tanks for $30

 

[wayne50f1]

i think the stainless is about 35 bucks free shipping
you can try one of the plastic ones to see if it helps, you can get them pretty reasonable, i think just being able to run the extra fluid in the car is the difference.
its been in the 90's here also and my car is runnin much cooler with it, no problems at all ,its diffently a cheap thing to try, try gettin one from a junk yard for a buck or two to try it first, fill it up half way and the radiator to the top, it may spill some at first, may take several cycles hot to cold before it finds its own level
even with mine i had to add more fluid to the tank several times, it kept sucking more and more into the radiator, use a new style radiator cap. 13lb seems to be the one.

 

[herdfan75]

Hey...thanks for the ideas. I have a stationary fan with a spacer, but I don't know if it's that close. I have the three row because it's an original air car (I just need the underdash unit and compressor). The cap I have is a Stant cap, not with the pressure release lever. Do you think it's running hotter than it should? I didn't know the oem spec was 165. But, with a 165, doesn't that mean that the thermo will just open a little quicker? It will still eventually creep up there wont it? I don't know if the water pump has been changed in the last 10 years, but it circulates fine...actually it circulates pretty quick and that has concerned me in the past, so that may be the problem. Also, I've read that the 65 1/2 has a different water pump than a 65. How can I tell the difference. Isn't one cast iron and the other aluminum? Thanks again.

 

[beechkid]

Yes, the 165 probably won't make any difference and you're right that the temp will go there anyway, but, when you don't know whats wrong and there have been mods, I always believe that you need to go back to OEM specs, then see what works and what doesn't.

With regards to the pumps, there is aluminum and cast iron......each has diffrent hose connection locations. That's all unless you're talking about the 260 V8...that's another story.

 

[craigh]

I picked up a cheap plastic one tank for when I am on the road. it fits on the water bag bracket, so all I have to do is take it off for show. They are about $4.00 at almost any autoparts store.

 

[herdfan75]

Ok guys...I looked at it again. I took the cap off and let it warm up. The water is circulating just fine, and I let it run forever with the cap off and the water level never came up to overflow or anything out of the ordinary. The only thing it did is when I rev up the motor a little, and then bring it back to idle, the water got really foamy. It didn't burp over or anything. I think it's just where I reved the motor and made it circulate faster. Anyway...could the cap be holding too much pressure? It's always fine with the cap off. It's a 13lb cap...new. It's the second one I've tried! Thanks

 

[Guest]

I am having the EXACT same problem, I am going to get a pressure test done tomorrow. I let the car run with the cap off also, foam, then the foam went away. Drove for a while and still coming out the overflow. I will be getting a overflow tank!!! I don't think I have a head gasket leak, no bubbles in the rad., but maybe a circ problem. I will post on what I find out tomorrow.

 

[Guest]

Well they say most likely a cracked head. The warmer the engine gets the crack opens up and lets the exhaust presure in. So now we tear out the engine, dang, the guy we bought the car from said the rebuild only had 2000 miles on it. Yes it was someone from here, but I can not find his posts. I do have others on my e-mail but I wanted to find the original.

 

[herdfan75]

Wow...sorry to hear that. My car runs great and it never overheats unless it gets really hot, and even then it doesn' t start moving up unless we sit in traffic a long time. Why do you have to tear the engine out to fix the head? Look at the bright side. This will give you the chance to install some nice aluminum heads, intake and headers. It's expense that you didn't plan on right now, but at least you'll know what is in your engine and know that you have new parts. These things happen...you'll be better off in the long run. I've been there...trust me!