Overheating in a '62...

[Edward Kenny]

It had to happen. I flushed the cooling system and changed the antifreeze in my '62 CDV and now I've overheated twice since.  Here's where I stand at the moment:

1) The cooling system was "burped" after the first overheat. I know this because I heard the unmistakable sound of a hearty belch   coming from what sounded like the engine block.
2) The top radiator hose is hot and the bottom hose is cool while the car is idling for 15-20 minutes with the radiator cap off.
3) A new thermostat and new hoses were installed when I did the antifreeze flush.
4) Neither hose has collapsed at any time.
5) I had to add new coolant after each overheat because each time the car cooled down, the radiator needed to be refilled. However, when topped off, the coolant would not be drawn into the system while the car was idling.
6) I am not leaking coolant.

Can anyone shed light on my overheating problems?? Thanks for the due diligence.

[35-709]

I would suspect the new thermostat, test it, or replace it again.  Also try filling the engine block itself with coolant BEFORE you put the thermostat in place.

[The Tassie Devil(le)]

It had to happen. I flushed the cooling system and changed the antifreeze in my '62 CDV and now I've overheated twice since.  Here's where I stand at the moment:

1) The cooling system was "burped" after the first overheat. I know this because I heard the unmistakable sound of a hearty belch   coming from what sounded like the engine block.
2) The top radiator hose is hot and the bottom hose is cool while the car is idling for 15-20 minutes with the radiator cap off.
3) A new thermostat and new hoses were installed when I did the antifreeze flush.
4) Neither hose has collapsed at any time.
5) I had to add new coolant after each overheat because each time the car cooled down, the radiator needed to be refilled. However, when topped off, the coolant would not be drawn into the system while the car was idling.
6) I am not leaking coolant.

Can anyone shed light on my overheating problems?? Thanks for the due diligence.

G'day Edward,

(1)   If you hear bubbling from inside the block, and the radiator is full, then you have a blockage somewhere inside the block, meaning that the water cannot completely fill the block.

(2)   Never warm up the engine with the Radiator cap off.   This allows the engine coolant to begin to get too hot before its' time.   I believe your car has a 12 to 15 pound pressure cap, and as such, the coolant boiling temperature is raised another 24 to 30 deg for a 15 pound cap.   Does that make sense.   Plus, the cold water is being brought into the motor from the bottom hose, and that will always be cooler than the top hose, which is the return line to the radiator, past the thermostat, and that should be hot.

(4)   The only hose that could ever collapse is the bottom hose, as that is the one which is at the intake of the Water Pump, and Collapsation, if it is going to occur will be a maximum pump speed, that is maximum engine revs, like driving at 6,000 rpm or above.

(5)   I am not sure if the '62 Cooling system is a recovery type, but if it is, the Radiator should be full all the time, and the radiator cap lets the water out at above the pressure on the cap, to the coolant recovery canister, and when the engine cools, the resultant loss of pressure sucks the water back in from the overflow canister.   If it isn't, then the water level will be about 2" below the top of the cap when cold.   This allows for expansion.

As far as shedding a light, check that the cap is the correct one, and not damaged in any way to stop the pressure release, and vacuum return flow of coolant if it is a Recovery one, or a simple release if a non recovery one..

Then if you suspect the Thermostat, put it in a pot of water, on the Wife's hotplate, and using her candy thermometer, but make sure she says it is okay, or you will be eating out for a while, and as the temperature rises, after you turn the hotplate on that is, see at what temperature the valve opens.   Then let it cool down to see when it closes.   Both movements should be smoooooooth and easy.   But, it could also be ever-so-slightly jerky, but should fully open and close.

The next think to do to determine if you have the correct amount on coolant is to thoroughly drain the system, including the block drain plugs, and measure how much water you put into the system when filling from empty.

Not enough water might mean a partially blocked block, and if it is blocked, no amount of water will cool it properly.

Bruce.

[Dennis]

Make sure your timing is correct and make sure the thermostat is installed int he correct direction.

JM2C,

D

[Jim Govoni]

I bet the thermostat is upside down. If not just try a new one.

[Jack Miller]

Hey,

1 try changing the thermostat (they do crap out even new or it can be in backwards)
2 you might have a clogged motor clean it out do a forward and back flush
3 with the cap off and the motor warm & running faster than an idle can you see the anti freeze flowing in the cap hole?
4 You said that you keep on overheating and are loosing no antifreeze? Find out where it is going. It has to go somewhere like a pot of water overflowing on your stove when it is boiling.
5 Disconnect the top and bottom hoses on the radiator. Put a water hose in the filler hole, does it flow as fast out as it is going it? When the thermostat is off the car and hoses off and heater hoses connected together do the same with the block. Does the water run through the motor without a blockage?
6 I once had a similar problem with an XK motor. It ended up being a crack in the head gasket causing the anti freeze to blow out the exhaust. You said that you keep on overheating and have no leaks or antifreeze leaving when this is happening?
If you are using anti freeze also check the exhaust and see if there is a green hue in the exhaust and around the rear pipe. See if there are any bubbles on your dip stick, Are you getting any bursts of smoke when you start the car when it was sitting a few days? If so Check the compression and look in each cylinder when the car is sitting and see if there is any anti freeze sitting on any piston.
7 Do you have any kinked hoses? (try this first)
8 nothing to do with this question but have you replaced your heater core? They go and then you will not be happy with what is sitting on your passenger side floor. I just did my 61.

Jack