I just picked up an aftermarket catch can for the radiator. Mine broke five years ago and have been running without one since. Finally picked up an aluminum can, but it's smaller than the stocker. It holds just under a quart. Will that be big enough?
Should be .... its just for expansion and should also be vented to overflow like the factory original bottle. I have a Felx-a-Lite Radiator and their aluminum overflow bottle is quite small maybe 10 inches tall by 2 inches in diameter ... probably about a quart also. Keep the radiator full and then put an inch of coolant in the bottom of the bottle. When the cap in the radiator unseats my bottle level rises to near the top but does not overflow out of the overflow bottle so I think you should be good. Just do not top of the overflow an inch or two should be good and just check it when its hot and has expanded into this tank ... then when it cools off it should suck it back into the radiator.
I hooked it up and let it idle until the thermostat opened. Can was half full at that point. Shut it off and just checked it now the fluid is down to about as third. I need to tap an npt fitting for a relief into the top. Other than that I think it will work.
yes mine id fine like this from Flex-a-Lite. Yes, the overflow has to be able ot overflow also. With fluid coming in, the air has to be able to displace out ... put it near the top.