Cool/Heat: 1965 Cruiser cooling problem?

[kruznstude1]

After driving for about 10 minutes, my Cruiser is losing coolant from the overflow hose. The temp is fine...any ideas?

[swvalcon]

If there is no pressure build up in the system or idle problems leaning toward a head gasket problem I would look at the pressure cap first.

[Buzzard]

You could have a circulation problem (crud in the water jacket) which shows after a little time and doesn't allow the coolant to properly circulate. When chasing these problems down, I have had great success in isolating the problem with one of the laser thermometer guns as you can check for anomalies all over the engine, radiator, engine block, heater (in & out) and hoses. I have solved a lot of cooling problems this way. If the motor hasn't had a recent rebuild (and hence a good boil out) then the crud can easily fill the engine's H2O jacket and become a restriction, but only showing up under load.
Good luck.
Bill
PS: You'll end up using the gun for all sorts of non auto related things (EG: Checking if your dog is still alive.)

[thunderations]

I agree with replacing the pressure cap first. It may be weak or have a split in the rubber gasket allowing the coolant to leak out the overflow. Always nice to add a coolant recovery tank too and most of them come with a new pressure cap.

[BobPalma]

PS: You'll end up using the gun for all sorts of non auto related things (EG: Checking if your dog is still alive.)

Is it OK to point one of those guns at a living animal? BP

[kruznstude1]

thanks...I'll check that!!

[kruznstude1]

Never had a rebuild...has sat in the garage for a few years. I had a local mechanic (and I use the word "mechanic" VERY loosely) go through the engine last year...he REALLY screwed me, and he replaced my pressure cap with a nice new shiny one...never had problems before...I'll get another cap, and start there...if no luck, I'll flush the system to see what happens. Thanks for the info...and that laser thermometer sounds like a great idea. As far as the dogs go...if they don't bark, there's a problem!!!

[mbstude]

Did you fill the radiator to the very top? Every Stude I've had would puke out a little if the radiator was overfilled.

[DEEPNHOCK]

Yessir. Spot on Matthew.
An 'open' cooling system will burp out a little water if filled to the top, and suck in air as it cools off.
After a few heat/cool cycles it settles down.
If the engine is not running hot... Don't make yourself crazy.

Did you fill the radiator to the very top? Every Stude I've had would puke out a little if the radiator was overfilled.

[kruznstude1]

The radiator WAS filled to the top.......I'm thinking replacing the thermostat with a 160 degree high flow thermostat, and getting an overflow tank...any comments would be appreciated. Would 160 be too low, or should I stick with the 180 degree. Also getting a new radiator cap with a pressure relief lever. Also noticed some coolant pooling behind the thermostat housing on the manifold. This should be corrected when thermostat/gasket is replaced...Thanks everyone for your input...it is much appreciated!!!

[Corvanti]

^ i believe you're overthinking this. as stated earlier, these radiators aren't meant to be filled to the top. get a new radiator cap at the proper pressure and maybe a recovery tank if it makes you feel better.

[mbstude]

The radiator WAS filled to the top.......

Sounds like your car is doing what it's supposed to.

[Alan]

Stude used a taller radiator cap than GM or Ford. The wrong cap and it won't build up pressure. Ran into the same problem when working at a Signal Station in the late 50's, put the right cap on it and no more problems.

[DEEPNHOCK]

If you get a coolant recovery tank, you need to get a 'closed' cooling system cap.
The diff between an 'open' cap and a 'closed' cap is this.
Coolant (and air) will get purged out when the PSI goes above the cap rating.
When things cool back down, an 'open' cap will allow air back in 'right at the cap'.
A 'closed' cap will only allow coolant back in through the tube.
So... Once the air has been purged out of the system, and only coolant allowed back in....
You have more coolant to keep temps regulated.
I don't think you will find a lever release cap for a 'closed' system, because you are breaking the seal with the lever.

The radiator WAS filled to the top.......I'm thinking replacing the thermostat with a 160 degree high flow thermostat, and getting an overflow tank...any comments would be appreciated. Would 160 be too low, or should I stick with the 180 degree. Also getting a new radiator cap with a pressure relief lever. Also noticed some coolant pooling behind the thermostat housing on the manifold. This should be corrected when thermostat/gasket is replaced...Thanks everyone for your input...it is much appreciated!!!