Overheating

Took my 63 LeSabre out for it's first official shake down run today. Everything was great except except that it was overheating.

I got about 10 miles from home, doing about 65 on the freeway. When I slowed down some, I noticed a ton of steam coming from under the hood. I pulled over and the entire engine compartment was soaked with antifreeze. I let it cool down, and then dumped about 4 gallons of water in. Headed home, but had to stop a couple of more times on the way home to let it cool off. Each time, it took another four gallons of water.

There are no leaks that I can see. It's losing coolant from the overflow tube, and out of the cap. I got a new cap, 16 lbs. I also picked up a thermostat, but found that there wasn't a thermostat in there to begin with. So that rules that out. What else should I check out?


Thanks!

 

Wow, losing that much water with no leaks, is the water pump working? Check to see if there if the water is flowing in the radiator. Check your belts too, for proper adjustment.

 

I'm afraid this isn't going to be much help but I had to comment. You were carrying over 12 gallons of water? Were you a boy scout by any chance?

 

Haha! No, actually I wasn't carrying any water! The closest thing from where I broke down was a Petco. I bought two 2-gallon jugs of "special" fresh-water fish water. Don't even ask how much it cost.

I kept the jugs, and filled them again in a burger king bathroom. Made a huge freaking mess there- and then again at the bridge authority using their spigot- got hollared at for that! Yeah, it was one of those days...

 

That is a LOT of coolant and or water to lose that quick.

Check the weep hole on the water pump. any fluid traces there indicate failure, and when under pressure those things can really blow a lot of fluid into the engine compartment.

In addition to searching for external leaks, consider an internal leak. You could have both. Again, 4 gallons seems to me a LOT of coolant to lose.

I would look at my oil to see if it had coolant in it. It would look like a chocolate milkshake. This would indicate a Headgasket leak - or a crack in the cast iron. The coolant can also be sent out the exhaust from a headgasket leak, usually you can smell it or see it as steam out the tailpipe. Worth checking, in my opinion.

Any major leak that doesnt let the system pressurize up will help your coolant boil off real fast.

Good luck!

 

The water seems to move after about 5 minutes of idling. It doesn't really "flow" in one direction, but rather swirls around.

 

The oil looks/smells/feels completely normal.

 

Also, I should add that it seems to only overheat while cruising at highway speed- 65 mph. I've let it idle in my driveway for about a half hour and it didn't overheat.

It has AC and a fan clutch. No fan shroud. I read something about the advance being off. Mine isn't connected to anything. What should it be connected to?

 

check your timing with the hose plugged in dist. if you advance the time some that will help cool the engine i believe.

 

Where does the other end of that hose go, exactly?

 

How old is the radiator? If old have it recored with a high performace core. I would tend o believe that where your problem is. Having a thermostat can only help.

 

check radiator
put new thermo in
put a shroud on
timing. there is a small rubber tube that runs from dist can to the lowest point on the carb. plug the hose to dist can and check timing. put it to around
8 to 10 btdc to start.

also a clutching fan is a good idea
hope this helps jim

 

There is a port on the back of the carb, at the bottom, but this is connected to a fitting the passenger side valve cover.

 

I also noticed that the fan is about three inches from the radiator. Does that sound right? I'm wondering if I should try and mout the radiator closer to the fan, or look for a fan spacer to try and bring it closer to one inch apart.

 

Make sure there is a spring in the lower radiator hose. If there isn't, on the highway the water pump will physically collapse the hose thus making coolant unable to flow. I'd check that first before pulling the radiator, especially if it only overheats on the highway. Good luck!

 

Well, in my attmepts to flush the radiator with a high power hose, I put an nice tiny hole in the core. This thing is trash anyway.

I've been doing some research, and what I found was that it looks like a radiator from a 64, 65 and 67 6 cyl Mustang might work. It is a downflow with the upper and lower hose connections in the right spot, and it has the trans cooler. It appears to be close to the same hight, but the width is a few inches shorter. I may need to make up a new bracket, because the filler neck is close to the center, where the original bracket mounts.

The best part is, an all aluminum model is only around $160.

I'm just wondering if the improved cooling of a 2 row aluminum radiator will still be beneficial even though it is about 5 inches smaller and designed for a 6 cyl?

 

I can answer that: NO

It will be way too small for a 401 with A/C.

I had my original radiator recored by a local shop with a 4-row core. That is what you need. I can drive with my A/C on in Texas summer heat and never have an overheat problem. I know lots of guys in Texas that went with a 3-row core and regretted it. Many paid a second time to have the 4-row core put in (painful on the wallet).

You will not find a drop-in replacement radiator for your car, complete with tanks, but a good radiator shop can put a new core in it (and clean the inside of the tanks).

BTW, my dad has had a terrible time with overheating on his car for the last 6 months. He tried all kinds of things. It turned out to be a slightly leaking head gasket. When he replaced that, all problems went away. He determined it was a head gasket by using some kind of indicator on the radiator filler neck. It changed color when exhaust gases came out through the filler neck. Too late to do that on your car now, with the radiator off, but when you get it all back together, have a shop sniff the neck of the radiator for exhaust.

Jim