For those of you running canton or other aftermarket tanks.


Do you notice coolant venting once in awhile out the side vent hole on the neck of the tank. (See picture)

Cooling system has been completely overhauled and bled multiple times. Level in the expansion tank is about half way. Also did a pressure test on the system and the cap. Both pass flying colors.

No issues with overheating.

just random it weeps out this hole.

Not sure if it’s normal or not.

I would say your coolant level is maybe a bit too high, or that pressure cap is not sealing correctly, or the cap pressure rating is too low....

I would run that overflow hose all the way to the bottom of the car so no coolant gets on anything in the engine compartment

Bryan

While everything tests ok, it could be a simple matter of the height of the neck and overflow spout on the tank not being optimal for the depth of the spring gasket in the cap. Allowing a small amount of fluid or at high pressure only.
I'd do the same, simply route the overflow out of the engine compartment and keep an eye on it for now.

Wondering if the cap I’m running is too low psi it’s 16psi. I know canton recommends higher.

I don't remember what it is, but you need to use what Mini recommends for pressure.
That's why I went with the round aluminum tank, uses the factory cap.

I have one of the Canton tank and had the suggested pressure cap on mine the pressure was too high. When the car would get warmer than normal it would never open the cap and leak out to the overflow it would push past one of the hoses on the radiator, I ended up going with the Canton 16lbs cap instead

Mini recommends 16psi and that’s what I use.

Ill take the suggestion to route the hose lower.

This is the cap I have on my car:
Can't comment on how good it is yet as my car isn't finished..

+1

I may be missing something. But my brain tells me routing the overflow hose higher or lower will not make an iota of difference. The hose is there just to direct the release of excessive pressure of steam/liquid. You likely don't have a problem. Just let the coolant lower than half and watch it closely for a while.

My Mini will spit coolant after a long session of intense track driving, and me no-worry as long as I check the level regularly.

I routed the hose lower so it wasnt dripping coolant down the side of the expansion tank and onto the heat shield. Instead its now dripping down to the ground.

Coolant level too high. Let it overflow on the ground until it stops doing that. Then check your coolant level. It should be filled to a little lower than that when topping up cold. You'll note that the OEM coolant tank is only about a third filled at maximum level when cold

^^'This^^ was another of my thoughts as well.
The actual level seems low when looking at it, but 1/3 - 1/2 is actually full.

I agree might be a tad full.

Hard to gauge it on these tanks.

Gonna use a little Popsicle stick or something to note where the level is at.