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MAP Catch Can/Coolant Combo - Normal to Need Multiple Top-Offs?
Hi Everyone,
Recently got my car back after a long-term build (full details in my build thread here - Build Details). The shop recommended and installed a Catch Can/Coolant Expansion Combo Tank by MAPerformance. I recently checked the coolant level and it looked low, so I topped it off yesterday with OEM coolant, making sure the float lined up with MAP's instructions (https://cdn.shopify.com/s/files/1/08...f?v=1654109320).
Went for a 10-20 mile drive yesterday and drove it fairly normal and did a couple pulls. This morning the float was down a bit, so I added a bit more coolant.
Is this normal behavior for a catch can/coolant reservoir combo versus the stock setup? I'm assuming it could be air purging from the system and normal circulation, but wanted to be extra cautious since this is a new setup.
Car runs perfectly fine - no CELs, no overheating, no visible leaks underneath. Worth noting: my drain kit on the catch can combo was leaking a bit, which I addressed a couple weeks back. Oil levels have been stable over the last 500-700 miles.
Leave the overflow empty, make sure the cooling system itself is full when cold. The overflow doesnt need to have coolant in it, and it is the worst way to verify the cooling system is full because its not really part of the system.
What you're observing is typical of a recently modified system with an expansion tank and oil catch can. As long as there are no leaks, overheating, or engine warning lights, you can assume everything is working normally and continue monitoring the oil level for a few days.
