Hi,

Im replacing the oil filter housing, a common issue with these cars. Yes its totally DIY-able, but take many hours. Given one needs to remove all these cooling hoses during that repair, figured I'd like to fully drain and refill the coolant.
That said, I cant find ANY drain plug or anything on the B46 (MCS engine). Does one exist? Ive googled everywhere, searched these forums and Youtube as well and nada. Best I found was this Bentley Youtube video for the 3cyl Cooper which doesnt apply.
Working on the car, all I could see to drain coolant from was the lower connect to the radiatior on the passenger side. But even that "lower" connection site smack in the middle of the radiator and so I can see theres tons of fluid still remaining. Is a pressurized method the only way to fully drain coolant from these cars?

Thanks for rany insights!

 

Nope, no drain plug, doesn't exist.

Also, the Bentley video, despite it being focused on the B36/B38 vs the B46/B48, very much does apply. No real variance in terms of getting the coolant out, and it does speak directly to the aux coolant pump in the S/JCW during its discussion of needed post-refill bleeding procedures.

But to your most direct question, yeah -- no traditional drain. Funny, I didn't think about that much, it was annoying to get some of the coolant out in messy ways, but everything in my oil filter housing was already gone due to the leak and me getting mad at the car (I let it sit unused and draining [meaning leaking] for a month out of raw spite, lol)

 

the Only way I heard to drain - is when the dealership swaps your coolant by sucking it out. GO FIGURE !

 

Im thinking maybe I can get one of those cheap fluid pumps at Autozone and stick it in the radiator opening and just get whatever remaining liquid I can out of it. They also rent a coolant pressure test kit at Autozone which I've read you can use to drain/refill coolant I think?
Honestly, would've been really nice to just have a friggin drain plug where it ought to be! Oh well.

 

@2014MCS_Miami you're reminding me of all the mental gymnastics I went through on the way to getting my water pump replaced (elective upgrade). The warranty conditions of the Meyle HD required a documentable coolant flush at (meaning immediately after put-together) installation, so I was careful to do the following:

(1) get the coolant out of the oil filter housing before replacement (the leak pretty much took care of that for me).
(2) drain the oil from the engine.
(3) replace the oil filter housing (part of that: getting as much coolant out as possible -- even TIS doesn't say you have to empty every last drop out of the engine or even close -- the main thing is to get it out of certain places by way of the gravity drainage that naturally happens when removing the hoses TIS instructs you to remove).
(4) refill engine oil, and top coolant back up (following TIS bleeding procedures to the letter).
(5) have the coolant system professionally flushed (a good idea anyway, because who knows what the oil filter housing's physical failure might have allowed to mix together).
(6) <when I got around to it> get water pump replaced, with coolant flush as part of the project.

Logistically this turned out to be a bit irritating, especially finding a shop that wasn't trying to gouge me for step 5 in particular, plus the shop that did the water pump replacement broke the electrical connector on the thermostat housing (annoyed at this -- but would have ended up replacing the housing sooner or later anyway because plastic). But I got it done.

 

@2014MCS_Miami Have you seen this thread that wound down last year? Didn't wind up with the solution you're looking for I think, but refreshed my memory and laid out a bit more detail on the challenges.

I had forgotten it was out there despite the fact that I put some of the details in it

 

I'm thinkin' next time they change my oil, to do coolant same time. F-56 is 10 yr.s old. mfg. date 7/14 Built by factory to sit on Miami's Mini Showroom floor & sell Minis

 

I def recommend all fluids. I know I'm going to start doing the following for all future cars I own: coolant, transmission fluid, brake fluid eve 50k miles.
Manual Trans fluid was easy on the F56 Mini, did it myself.
Coolant is a nightmare, need to remove fan to gain access and it never fully drains as it doesnt have a proper drain plug. Best bet is a pressurized flush system which arent that expensive if you're a DIY'er. Brake fluid I have yet to do and will be googling for DIY's pretty soon. Oil is easy but messy so I hate doing it. I always find a $99 dealer coupon for it anyhow, but I feel they overtorque the OFH which is partly what leads to it breaking eventually.