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Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Clubman (R55), Cooper and Cooper S(R56), and Cabrio (R57).
So I've been troubleshooting a coolant mixing issue with my Mini for about 2 months, started with the oil system full of coolant. My first thought Head gasket, so I replaced head gasket, turbo, oil cooler, Thermostat, intercooler. Today was supposed to be her first start up since the rebuild.
I filled with fresh oil and filter, new coolant. Just before launch I checked the oil, BOOM full of coolant/water up to its gills..... Drained oil/water; as i pour water into coolant tank it flows out of the oil pan.... WTF is going on.
Could it be the oil filter housing? Cracked block? This Mini is Going to he the death of me. Thinking about throwing in the towel however now im 3k dollars in parts and still owe 9k on a car I've literally driven less than a month. Very upsetting.
You might want to compare your coolant and oil hose connections with the RealOEM illustrated parts list. Sounds to me like you bought the car used and discovered the problem while getting familiar with it. Whoever did your repairs probably just reconnected everything the way they found it. My guess is, the previous owner switched hose connections during a repair, then sold it ASAP. I sure hope I'm wrong. When it was drivable, how did it perform?
If your hoses are all routed and connected correctly, about the only items left where oil and coolant co-exist are the block and head. My oil cooler and filter housing are two separate pieces, and I don't know without a closer look, whether or not coolant flows thru the filter housing. Hopefully you got two new gasket sets --- between the two pieces and the block.
There is coolant going through the oil filter housing, there is a molded gasket between the block and housing , and a second one between the oil filter housing and oil cooler. I wouldn't think this would be the gross leak that you have now. Maybe try and put a little air pressure on the coolant side and listen for the leak?
yes, when I replaced the oil cooler I used new gaskets on both sides of the housing, All of the coolant hoses are correctly attached. I was thinking maybe the oil filter housing is busted inside? I've never seen this before. as I pour coolant into the reservoir it flows right down to the oil pan.... I was thinking about re-doing the head gasket but OMG thats a huge job! I was like maybe I put the gasket on upside-down but it only fits one way!! lol.
Did you actually replace the oil cooler with a new one? If not then the most likely culprit is the oil cooler, they do fail internally, seemingly an uncommon failure.
I suggest replacing the cooler before assuming the head, head gasket or block has failed.
I suppose pressure testing won't hurt, but it is not clear that it will show you where the internal leak is.
I can't think of any hoses that could be swapped that could cause your symptoms.
Why did you replace the turbo and the intercooler?
Did you actually replace the oil cooler with a new one? If not then the most likely culprit is the oil cooler, they do fail internally, seemingly an uncommon failure.
I suggest replacing the cooler before assuming the head, head gasket or block has failed.
I suppose pressure testing won't hurt, but it is not clear that it will show you where the internal leak is.
I can't think of any hoses that could be swapped that could cause your symptoms.
Why did you replace the turbo and the intercooler?
yes, I installed a brand new oem oil cooler. I replaced the turbo and intercooler because they were both full of water/coolant, thought maybe the turbo was junk so i figured whilst I'm in there id upgrade them instead of trying to clean them. Lol.
MYSTERY SOLVED!!!! Ok so I would recommend everyone with a N18 to pull their Valve cover and make sure the aluminum plug in between the two center spark plugs is still pressed firmly in the head. Found out after 3 months and two head gaskets that the issue was a stupid little freeze plug for the heads water galley. 😡 Should be back up and running as soon as my next order of bolts and gasket shows up!
Last edited by DPMinis11; May 18, 2017 at 11:23 AM.
Reason: Pictures
Well done and thanks for the information! I updated the thread title to make this information easier to find for the next Mini owner with this problem.
Were you able to order a replacement plug? Plug is not shown as a separate item on realoem.
NO, Mini does not offer a replacement part. they apparently take their head to a machine shop to have fixed....
I Tapped and installed a threaded plug to solve the issue FOR GOOD.. LOL
Given that you live in Vermont, you know why engines have freeze plugs, right? I spent a dozen years in upstate New York, Vermont, New Hampshire, and the Boston area, the day I decided to move back to California it was -11F.
Since you tapped it and put in a threaded plug, make sure you keep your anti-freeze properly mixed and topped off.
This brought back a memory, many, many years ago I was driving with my girlfriend in Florida when the car suddenly overheated. We pulled off, I checked the engine and the coolant was gone. No split hoses or other obvious problem. When I added water to the radiator, it poured out of the side of the engine block - the freeze plug had fallen out.
I live where nobody works on mini coopers, and need the plug that you had to get. (see below) could you forward this information to me so i can get it. everybody here and dealership is saying i need to replace the head because they can not get the part. [img]blob:https://www.northamericanmotoring.com/f6678320-0af2-4623-b3ab-770473a70080[/img]
ThankYou in advance
Originally Posted by DPMinis11
MYSTERY SOLVED!!!! Ok so I would recommend everyone with a N18 to pull their Valve cover and make sure the aluminum plug in between the two center spark plugs is still pressed firmly in the head. Found out after 3 months and two head gaskets that the issue was a stupid little freeze plug for the heads water galley. 😡 Should be back up and running as soon as my next order of bolts and gasket shows up!
