Canton Coolant Expansion Tank Expelling Fluid

[MaximumSVT]

Just finished installing Canton part#80-232 coolant expansion tank for the radiator. Once installed, I backed the car into the driveway to check for leaks. The fitting right behind the radiator cap began to expel a large amount of coolant and continued to do so until I shut the engine off. Is this because the tank holds less? Or is there some other issue? My car has never overheated or lost coolant to the best of my knowledge with the stock system. Thanks in advance.

 

[evans03c]

If you're sure it's not a bad seal at the cap or at the hose my guess would be that some air got into the system when you were doing the swap. Here's the burping procedure in case you haven't seen it before.

Check all hose clamps for correct tightness. Make sure the radiator drain**** is closed.
Place the heater temperature selector in maximum cool position.
Remove the pressure cap from the cooling system reservoir and the fill plug from the engine crossover tube.
CAUTION: Do not fill the cooling system through the reservoir only. Coolant will not enter the engine. Only the reservoir and the radiator will be filled and engine overheating will occur. Add coolant into the fill neck on the engine crossover tube until coolant reaches the top 6f the fill neck on the cooling system reservoir.
Install the cooling system pressure cap on the reservoir.
Continue to fill the cooling system at the engine crossover fill neck until full.
Install the engine crossover tube fill plug.
WARNING: To avoid the possibility of personal injury or damage to the vehicle, do not operate the engine with the hood open until the fan has been first examined for possible cracks and separation. CAUTION: If the engine temperature gauge does not move, coolant level is low in the engine and must be filled. Stop the engine, allow to cool, and rill the cooling system as outlined. Run the engine until the thermostat opens (coolant flowing through the radiator lower hose becomes hot).
Stop the engine and allow to cool.
Add coolant to the engine crossover tube fill neck until the cooling system is full.
Install the fill plug.
Repeat the fill procedure if necessary.
Bleeding

Select the maximum heater temperature and blower motor speed settings. Position the control to discharge air at A/C vents in instrument panel.
Start the engine and allow to idle. While engine is idling, feel for hot air at A/C vents.
CAUTION: If the air discharge remains cool and the engine coolant temperature gauge does not move, the engine coolant level is low and must be filled. Stop the engine, allow the engine to cool and fill cooling system. Start the engine and allow it to idle until normal operating temperature is reached. Hot air should discharge from A/C vents. The engine coolant temperature gauge should maintain a stabilized reading in the middle of the NORMAL range. The upper radiator hose should feel hot to the touch.
Shut the engine off and allow the engine to cool.
Check the engine for coolant leaks.
Check the engine coolant level in the degas bottle/coolant expansion tank and fill as necessary.

 

[BLK03SVT10TH]

If your talking about the 1/16-NPT hole in the filler neck right under the cap, you will need to buy a Plug for that hole at Home Depot in the plumbing section. That hole is to go to a Coolant Overflow bottle, our cars don't have one. Mine did exactly the same thing.

 

[BLK03SVT10TH]

This image should be visible some time tomorrow. (DNS Server problems)

 

[MaximumSVT]

Thanks for all the replies everyone. As it turns out, I didn't have the cap tightened all the way. Sometimes the simplest things are overlooked.