Found oil pan full of coolant, when I started pulling the head I found a freeze plug in the cam chain! Upon investigation I found that it belonged in the cylinder head right by number one spark plug. Why should this have happened?

 

I really thought this would start some discussion, if anyone has this same issue it's a major mess! That plug is about 1&1/4 inch, and if it goes out like mine did, it dumps all the antifreeze right down the timing chain to the oil-pan. I let it sit about a week before I took it apart, and now see some rust on the exhaust cam (bummer). Beyond the obvious "mess" I also see that I could use some valve guides, and wonder about the incredibly large carbon build-up in the exhaust ports. Hope someone wants to help~

 

I think I remember reading a couple threads about that freeze plug, but I don’t think it’s a common occurrence. Not sure the cause either. If you have to pull the head to fix it, a full head refresh sounds like a good plan, along with timing chain service.

 

It seems to be a rare failure. I'd be interested in pics of the exhaust valves.

Repairing the freeze plug ought to be a fairly simple task. Consider locating an oversized plug. I did a search on "oversized engine freeze plug", this link was among the responses: https://ussealparts.com/engine-block...eze-plugs.html.

If you lack either the skills or experience to do this, your best option is to have a cylinder head re-builder replace it.

How did you assess the valve guides?

Further details would be helpful, details such as: engine, miles, previously overheated, previous owners, other cooling system problems?

 

What I have is a N12, '09 Clubman with 120,000 on it, never overheated, however just did the thermostat. We got it from a BMW used car dealer in Concord, I think I'm the second owner. I assessed the guides by noticing that I could move the open valves sideways before I took the cam out. I need to remove some valve springs to test more but don't have that kind of valve spring tool. I've been working on cars for at least 55 years, did about 4 or 5 years in new car dealers as a wrench, then did a couple years as a snap on dealer before coming home to the family plumbing & heating business. While doing all this I built a very complete machine shop. I can do the work, but have other things I'd rather be doing!!!
Thinking of getting a reconditioned head, but don't like to trust other peoples work, can you recommend any?

 

Looking at this one on that famous auction site, https://www.ebay.com/itm/28403790285...yABEgKt0PD_BwE Does anyone have any opinion on these heads?

 

to remove those springs here is a link to the tool kit required for removal and installation of the intermediate lever springs.now you can try the knock off's which are much cheaper. i have seen people disassemble the heads without the tools and some how manage to spin the eccentric shaft gear on the shaft. FYI to remove head you dont need to pull any of the valvetronic apart if your planning on just swapping heads. you still need a timing kit but there like $30-50.

 

I am doing a swap, I have the cam locker kit, but what's the "timing kit"?

 

Im assuming we're talking about the same thing.

 

That's the tool & I'm using it today, all parts collected, just finished torquing the head - now for lunch and back to work on it. Did the water pump and water pipe yesterday - Can anyone think of anything else I should watch out for as I reassemble, so as to not be in here twice! (it's a long way in)

 

Hey, all. I'm new here but have been lurking since I bought my 2013 Cooper S back in May. I'm posting here because this thread is somewhat close to what I currently have going on, and I'm looking for some advice and insight.

Bought in May '21. Roughly $13k. 86k miles or so. Check engine light was on, but they said the had done something (can't remember what) and forgot to reset it. No problems after coming off the lot.

I took it to the MINI dealer to give it a once-over. Said it was in great condition but the front passenger shock (?? I'm not really a car guy, so that might not be the correct term/part) was leaking. I took it to a mom-and-pop shop for a second opinion. They could replace that for $200 less than the dealer, so we did that. They said the car was super clean.

Later this summer, my daughter and I swapped cars while I taught her how to drive her manual Mazda 3 (three lessons, I'm kind of an awesome teacher). We swapped cars back toward the end of September or early October. I got in my car the next day and the low tire pressure light and check engine light were both on. Grrr. Driving kind of jerky.

The next day or so, I drove it to work (30 minute drive), and with about 10 minutes left, it started overheating—yellow light, then red light. No coolant smell at all. When I was able to check, the reservoir was bone dry. Got some coolant and added it. Tried scheduling with the mom-and-pop, but couldn't get in touch. Finally made an appointment back at the dealer in early November.

They said that it either needed a fuel injector replaced $1200 OR sending the cylinder head out "to get walnut blasted" (service manger's words) for $4000. Recommended doing the fuel injector and seeing what happened. Said the coolant was low but they topped it off. Oil pan and water pump had a crack, but could wait. Did new brakes.

Mid-December, I was making the same drive to work and I smelled coolant the last 10 minutes. I think I put more coolant in when I got home (I honestly can't remember—it was a busy time). A few days later, my daughter and I were coming home and got on the the freeway. Popped it into Sport mode to zoom over the the left lane. Then it started jerking big time. Got off the freeway and over to the right with my blinkers on. The Low Power Mode light came on, Check Engine light flashed a few times and went out. Started over heating (yellow then red). Pulled over to the shoulder and turned off the car. Tried restarting a few minutes later and it wouldn't. Turned over the first time, but then wouldn't turn over. After another 10 minutes or so, it did restart. I put the defrost on high and drove it to the mom-and-pop shop (Sunday afternoon) and dropped it off. 20 minute ride, and the air never heated up.

They said that they were getting misfire codes and would need to start breaking down the engine for further testing, up to 8 hours @ $1000.

Drove it home with the intention of getting back to the dealer for a second opinion. Checked the codes, and it was giving random misfires on all 4 cylinders. Stuck thermostat.

I started doing some research and decided to flush the coolant and put all new coolant in and bleed the system. Seemed to need a LOT of coolant. When I went to start the car after bleeding it, it wouldn't turn over. Looked back in the coolant reservoir and it was black (definitely had some oil in it before I drained it).

After doing some more research, I checked the oil, which looked like a chocolate milkshake. My research had me thinking head gasket (hopefully!).

Had it towed to the dealer and they found that a freeze plug broke out. Engine was full of coolant. Talked to them lat today and the said they drained the engine and put the head back on to see if it would start and it wouldn't.

Their recommendation was that it wasn't worth it to fix. That the damage could go further, to the lower part of the engine. I asked how much it would cost to put a rebuilt engine in. He said "we don't do that, but you're looking at like $9000."

Does any of this sound legit?? Does anybody have any advice?

Could the disappearing coolant from November have been a harbinger of something going on that should have been looked at more closely? Did I kill it by trying to flush the coolant?

Thanks so much!
victor