[waxfigure]

I have a 2016 M235i. Mine blew last year around 45k miles while I was driving back from Los Angeles to Laguna Beach. I instantly thought "damn all the horror stories of owning a BMW are true!" as I had never experienced anything like this with any other cars even after 100k miles.

It was around 11 pm when it happened. I first noticed white smoke coming out from a car in front of me and thought to myself "damn that sucks". After driving for 2~3 minutes on a straight road I came to a stop at a red light and noticed the smoke was actually coming from my car (looked like it was coming from the driver-side wheel).

I pulled over and called BMW emergency assistance (my car was still under CPO warranty at the time) and I remember getting seriously frustrated with the agent as she said they couldn't do anything about the car until a warning light came on and that I would have to try to drive my car back home until a warning light appears. After spending some time trying to convince her I decided to leave the engine on and see what happens (obviously I had no idea it was the coolant hose at the time). After leaving the engine on for another 2~3 minutes the light finally came on and she agreed to send a tow truck to tow it to Irvine BMW.

Picked up the car the next morning from the dealer with the hose replaced. This was the only "service" that I got from the CPO warranty. I'm at 55k miles now, out of warranty, on stage 1 and have had no other issues since.

[oooseun]

Same here, 52kmi, out in the middle of nowhere (a state park with no service) mine decides to call it quits. It was a scary cold night, but eventually a stranger helped drive us into town to get a truck. Seeing smoke come out of your engine 1000mi away from home makes you start questioning a lot of things lol

[waxfigure]

Originally Posted by oooseun

Same here, 52kmi, out in the middle of nowhere (a state park with no service) mine decides to call it quits. It was a scary cold night, but eventually a stranger helped drive us into town to get a truck. Seeing smoke come out of your engine 1000mi away from home makes you start questioning a lot of things lol

I totally feel you. I'm at 55k miles now so the new hose has been on for about 10k miles and it looks like its already wearing out. I might as well buy an extra one and carry it around in the trunk....

[Efftooto]

I was getting the ECS Transmission kit (fluid, gasket, pan etc.), and noticed the hose was like $35 - my dealer wants like $80 (CAD), so I said to myself "Won't hurt", and ordered that as well. Was in the trunk maybe 3 weeks (at 100,000 km) and got home one day and there was the smoke/steam coming out of the hood near the driver's windshield. Lucky I guess.
Next order I'll grab another one!

Chris

[Moel]

77600 miles! And guess what just exploded on my M235i!!

Yep this effing hose. Now waiting 2 hours for the AA

[overcoil]

Originally Posted by Moel

77600 miles! And guess what just exploded on my M235i!!

Yep this effing hose. Now waiting 2 hours for the AA

r u on the side off the road ?

when mine exploded I bought 8 gallons of distilled water and filled the radiator with a gallon drove five-miles, stopped, added another gallon, drive five-miles etcetera.

[Moel]

Luckily I got to a car park when I noticed it had let go.

I’d just put a bit of petrol in and always like to give it the beans on the drive home. Swung into the car park in the shopping centre near home, thought “hmm the new Dominos pizza shop has made round here smell quite rank”

It was at that point I realised there was a lot of steam escaping under the bonnet.

As I get the AA with my bank I enjoyed two peaceful hours in a car park, without kids eating a jumbo sausage and chips.

Off to BMW parts department tomorrow morning to be bent over the desk if the part is 50usd I can only imagine what it is here in the uk.

[iloughman]

Same thing just happened to me. Did anyone try connecting the hose back to the fixture? I super glued the hose at the break point back to the fixture but then decided it was foolish to drive 50mi from my current location to the nearest dealership that had the part. Leaving the car alone and waiting to get the new part mailed to me.

[Moel]

Well that didn't turn out so bad...

Rang them up on Saturday Morning, didn't have the part on the shelf, quoted me £62 for a replacement.

Just picked it up, and the guy must have mistyped on the parts computer for two, as it came in at £32

Will fit it and give the car a bit of a wash later as a treat

I loughman, I wouldn't be using superglue... even if it were to hold the pressure, super glue is brittle, and would likely go under any torsional stress over rough roads, so you're doing the right thing waiting for the postman!

[Moel]

further update, the pipe is attached and after a 6 mile run out this morning, we have temps of 102 degrees c.

I'll take that, next up...start saving for water pump and thermostat.

[Moel]

Ok

So i'm now a little bit more concerned....just been out for another drive... stopped, and again steam coming out of the bonnet.

Couldn't specifically see where, limped it home took a better look...it would seem there is some sort of failure that has occurred where the upper coolant hose enters the oil cooler housing. It seemed loose as prodding it at the failed end, allowed more hissing and steam to escape.

2 coolant hoses in 3 weeks? Should i bite the bullet and just do the lot plus the water pump?

Is the water pump failing and causing over pressurisation of the system causing these pipes to fail?

[p912guy]

This thread is one of the reasons I love this forum. I had a low coolant warning a few weeks ago and added some distilled water to the system and everything was fine until I went out to the car to go home for lunch today and got the warning again. When I got home I popped the hood and could see I had some type of coolant leak, so I left the car in the garage and drove my truck back to the office. I did a quick search and found this thread. Betting the odds are this is my problem. I'll investigate more when I get home tonight.

[RichardC300]

Just replaced mine pre-emptively at 52k miles. Had a microfiber wrapped around the driver side, but it still gushed coolant for a second until the line almost emptied. If you care about some coolant dripping down, maybe detach from the reservoir first and empty the line first to minimize how much drips out.

[msej449]

One of the few things not covered by my UK BMW extended warranty to 100K miles are the coolant hoses. Which tells you a lot about how fragile these must be. And why replacing them pre-emptively is a good idea. From forum posts in the US and UK, the most susceptible to failure seems to be the overflow hose at around 60K miles (see the preventive maintenance schedule I compiled from forum posts below).

View post on imgur.com

Note the suggestion to have the coolant liquid replaced at 35K-40K using a vacuum pump. My local BMW garage were quite happy to quote for this, unlike some of the other work - such as replacing the charge pipe or auto gearbox oil.

There's an argument for replacing the overflow hose at the same time as replacing the coolant @35-40K miles, which should take you to the 100K mark for the hose MTTF (mean time to failure).

[ggggbmw]

Originally Posted by msej449

My local BMW garage were quite happy to quote for this, unlike some of the other work - such as replacing the charge pipe or auto gearbox oil.

I did the transmission fluid this summer at the 50K mile mark. What a pain. Doing transmission service is always messy, but doing the trans fluid on this car is real pain. Access to the fill plug is really restricted, and having to fill and close it while the car is running and transmission is warm is a sloppy mess. I can understand why shops would avoid doing this service.

I'm curious on why you state that you need a vacuum pump to service the coolant in our cars. Many BMW's do, but the 2 has a nice auto-purge function that runs the coolant pump to clear out any air. Worked really well for me when I swapped the overflow hose and used the opportunity to dump/refill about half the coolant with fresh. Draining by pulling the hose off the pump is a bit of a mess though.

[msej449]

Originally Posted by ggggbmw

I'm curious on why you state that you need a vacuum pump to service the coolant in our cars.

That's just the result of my search through the threads on preventive maintenance here and in the UK. There seemed to be two schools of thought: about ⅓ posts on the topic said it wasn't necessary vs about ⅔ saying it was better if one was used. I got the impression it was one of those areas where a mechanic in a workshop would use one by default, and while it's possible to do the job without one, it's not ideal.

The transmission oil replacement threads followed a similar pattern: some people said it was DIY-able (and had done it, like yourself) but there were a number of responses which described the complexity of the process and problems in getting it wrong, and recommending it was undertaken by a ZF-certified specialist who would have all the temperature monitoring and dialysis (my term) equipment.

I suppose my chart is more aimed at people like me, whose days of DIY mechanics are long past, and who will usually get more complex stuff done by a dealer, independent or specialist.