[eleven11]

Originally Posted by daniiwsz

Hello guys, just had the same problem with a major leak of coolant and received some very bad news...

Nope.

[alexonahurry]

Originally Posted by daniiwsz

Hello guys, just had the same problem with a major leak of coolant and received some very bad news, what alexonahurry described apparently happened to me as well, tought it is just the water pump that failed, but apparently received from the service some videos where they took off everything under the hood to find the cause. Not really sure 100% what were the parts that literally broke, but from what I understood it is related to an oil part, plastic parts which completely got broken, including the water pump which had some leaks and the plastic connector to the cylinder, in a matter of minutes the whole coolant was going on the ground.

Wanted to share the story, the car is still in service, they told me that several 30i models got into service with almost same characteristics and in their case apparently the whole engine had some infiltrations which lead to a completely broken engine, anyone knows anything about this ?

The car is a 330i xDrive 2017 with just 90.000km, I am literally shocked how this could happen, it was out of nowhere, no signs no anything, really considering selling ASAP, can anyone share if there are some known issues with the engine ? Thank you.

The cooling system seems to be the weak point on some B48 engines (oil filter housing, water pump and vent line), even with low kms. Other than that they are great. Did you fix your car? If yes, then I would keep it cause there are no other known major issues.

[GeorgeF31]

Originally Posted by alexonahurry

The cooling system seems to be the weak point on some B48 engines (oil filter housing, water pump and vent line), even with low kms.

You keep making posts to this effect. Do you have ANY hard data to back this up? A handful — or even several handfuls — of anecdotal references from a Facebook group or forum doesn’t begin to enter statistical relevance to how many B48 engines are in circulation.

While there has been a U.S. recall on a line in the coolant system, that’s one known element not the systemic ticking time bomb you describe. Any poorly maintained automobile stacks the odds against it for large failures. None of this is to say that some future development might place the B48 at the table with N20 timing chain failures or any of the other well-documented BMW engine debacles. But right now, several tens of thousands (at least) of B48 engines are in the field without any documented major failure rate.

I am truly sorry if you have experienced large failures with your B48, but lots of people run across these posts while doing car research or making maintence decisions. Misleading sweeping statements lead people to make poor decisions and waste money.

[alexonahurry]

Cause the almost similar B46 doesn't have these issues doesn't mean that they are entirely the same engine. Different operating temperatures due to US emission standards bla bla bla. These B48 engines are known for having issues with the cooling system - my dealer had dozens only with OFH crack - and the vent line is a recall for b46 AND only in the US. Many many B48 owners in our FB group (UK and Australia) have experienced similar issues, even Mini owners experiencing the same issues with B48 equipped cars. The US with its B46 might not be affected as much but believe it or not but there is a word outside the US with a lot B48s and most owners are not registered users in this forum . . . .

[daniiwsz]

GeorgeF31 we are here to discuss the problems that are appearing to this model, I do not believe anyone is here to make a bad review or to have some bad publicity, Alex is just presenting some facts which appears to be true, and I can confirm that since I just took the car out of the BMW authorized service.

alexonahurry yes, just took the car out of the service yesterday, and everything that you described earlier was indeed the case for me, the full checkout with the parts codes below.

11118511205 - Aluminum Engine Block Connector Pipe // which this seems to be the case for the recall, the code seems to be different as I am located in Europe, perhaps it differs
11428585624 - Engine Oil Cooler which apparently is part / or it was affected by the oil house filtering, had to be changed as well
11428596283 - Oil Filter Housing - WHICH APPARENTLY WAS FULLY CRACKED, this being the major issue for the cooling system fault
11518638026 - Coolant water pump

So..everything that has been discussed regarding the coolant system fault happened to me, so George, indeed many faults can happen due to the not properly handle or service of the car, but I got the car at 70.000km from a 1st owner, all the services included in the genuine BMW shop, even though, not really sure how it's bad is possible to handle a car in order to experience these issues, it seems clear to me that either there are some factory issues that soon will happen to all owners, either the parts/components are just bad.

Given all of these, I still have about 2 things that are buzzing my head, is anyone experiencing a low to medium shake after the car is started with the engine warm? I am talking about idle shake, same in parking / neutral, only before the engine is being started, sometimes the car is shaking pretty rough ) spark plugs changed 10.000km ago with OEM.

[2017F30]

Originally Posted by alexonahurry

Cause the almost similar B46 doesn't have these issues doesn't mean that they are entirely the same engine. Different operating temperatures due to US emission standards bla bla bla. These B48 engines are known for having issues with the cooling system - my dealer had dozens only with OFH crack - and the vent line is a recall for b46 AND only in the US. Many many B48 owners in our FB group (UK and Australia) have experienced similar issues, even Mini owners experiencing the same issues with B48 equipped cars. The US with its B46 might not be affected as much but believe it or not but there is a word outside the US with a lot B48s and most owners are not registered users in this forum . . . .

You’ve repeated this; however that’s not the case - my Canadian B46 vehicle had the vent line replaced under recall at the invitation of the service advisor.

[alexonahurry]

Originally Posted by 2017F30

You’ve repeated this; however that’s not the case - my Canadian B46 vehicle had the vent line replaced under recall at the invitation of the service advisor.

I wasn't aware that the B46 was delivered to Canada as well. Seems to be a recall for all B46 equipped cars then. At least you guys don't need to pay the 1K Espresso at the dealership

[GeorgeF31]

Originally Posted by daniiwsz

GeorgeF31 we are here to discuss the problems that are appearing to this model, I do not believe anyone is here to make a bad review or to have some bad publicity, Alex is just presenting some facts which appears to be true, and I can confirm that since I just took the car out of the BMW authorized service.

I have not at any time disputed the facts of his situation or that problems can and will happen to the engines. Nor do I debate the need to discuss problems and whether they are prevalent or not.

I will continue to call out unsupported generalizations.

[tpoddar]

Posting here to give an update on my B48 320i running a custom stage 2 100 RON tune. My engine has a strange issue with all 4 spark plugs severely fouling with oil and consequently causing misfires. I am currently waiting for a new valve cover hoping that it'll solve my issue. Note my compression test is good so it seems that there's something else is wrong with the engine. Any ideas? Will keep the thread updated as I further go deeper in the diagnosis.

[PradoRdz]

Originally Posted by daniiwsz

Hello guys, just had the same problem with a major leak of coolant and received some very bad news, what alexonahurry described apparently happened to me as well, tought it is just the water pump that failed, but apparently received from the service some videos where they took off everything under the hood to find the cause. Not really sure 100% what were the parts that literally broke, but from what I understood it is related to an oil part, plastic parts which completely got broken, including the water pump which had some leaks and the plastic connector to the cylinder, in a matter of minutes the whole coolant was going on the ground.

Wanted to share the story, the car is still in service, they told me that several 30i models got into service with almost same characteristics and in their case apparently the whole engine had some infiltrations which lead to a completely broken engine, anyone knows anything about this ?

The car is a 330i xDrive 2017 with just 90.000km, I am literally shocked how this could happen, it was out of nowhere, no signs no anything, really considering selling ASAP, can anyone share if there are some known issues with the engine ? Thank you.

my b48 has a coolant leak but after I checked I couldn't find where it comes from. Any suggestions of how to detect if its the OFH?

[tpoddar]

Originally Posted by tpoddar

Posting here to give an update on my B48 320i running a custom stage 2 100 RON tune. My engine has a strange issue with all 4 spark plugs severely fouling with oil and consequently causing misfires. I am currently waiting for a new valve cover hoping that it'll solve my issue. Note my compression test is good so it seems that there's something else is wrong with the engine. Any ideas? Will keep the thread updated as I further go deeper in the diagnosis.

Valve cover changed but no improvement. Oil fouling is worst in cylinder 4 but compression numbers are good. Getting a leakdown tester to further diagnose the engine. CCV hoses have no indication of clogging or anything weird. Question - Will a worn piston oil ring show up in a compression AND/OR leakdown test? Can scored cylinder walls cause oil fouling in a cylinder and would a leakdown tester help diagnose that?

[daniiwsz]

Originally Posted by PradoRdz

my b48 has a coolant leak but after I checked I couldn't find where it comes from. Any suggestions of how to detect if its the OFH?

No idea I'm afraid, it took some time also for them to figure it out. I would start first by changing the connector parts discussed on the thread, especially if you are not doing it in an authorized service, it seems the most common and easily task to perform.

[mike25resident]

Just sharing all the parts i changed in order to fix the coolant leaks on my f30 330i, after all this i have no more leaks, it started at about 70000 miles, first one to go was the oil filter housing and then all of these got replaced:

Oil Filter Housing (11-42-8-596-283)
Water Pump (11-51-8-638-026)
Coolant Vent Hose (17-12-9-845-173)
By-Pass Hose (17-12-8-616-914)
Engine Connector (11-11-8-511-205)
Turbo Coolant Hose - BMW (11-53-7-643-226)
Water Pump Assembly Gasket (11-51-7-644-809)
Expansion Tank Bleeder Screw (11-53-7-793-373)
Expansion Tank Cap (17-11-7-639-020)

And by the way im the second owner, all services where done on time and i was doing the services ahead of the service interval, also i had oil leaks too, so it seems it's something that we know from older BMW's, its just a matter of when it will happen, all of those parts a pretty much plastic so i guess it's expected.

[daniiwsz]

Yeah, seems definitely that this is a common issue to this model.

We changed almost the same parts.

[cjv2]

First time posting here -- I have a B46 engine living in a 2017 Mini Cooper S, USA location. Appreciate this thread and the forum, while figuring out a host of things about the B46 and other stuff (coding) I have found information here again and again.

Just wanted to offer that the oil filter housing (OFH) on my B46 went kaboom as well. I got pretty lucky (so far at least), so just as a data point for interested parties here's what I dealt with.

- Bought the car used at about 74K miles. I am the 2nd owner, 1st owner was definitely not technical but most signs are she at least tried to keep up on maintenance via a dealer.

- 1st oil change I noted coolant in the reservoir was well below minimum.

- Later checks made clear that coolant was "going somewhere."

- Local independent BMW/MINI shop advised that 3rd gen MINIs (and therefore the B46 engine) "do that." (maybe, but probably because stuff is wrong, IMO).

- While doing other engine work, noticed a good amount of dirt and historical gunk sitting atop what I did not realize at the time was the top of the OFH. That location sits below the intake for cylinders 3 and 4 and I confirmed that oil had been leaking from the intake there for a bit. I was less familiar with the B46 at the time so I did not connect the dots, and assumed all the dirt/gunk was from said oil leak. Nope. I would ultimately learn it was coolant (and dirt).

- Early Feb 2023 had a cold snap and found the climate control produced no heat. Scanned for codes and found a very alarming "20A50A: Engine cooling system: protective function for turbocharger coolant pump due to dry running active." Put the car in drydock until I could get around to identifying root cause, which I expected to be a coolant leak.

- Replaced the OFH (with my own two hands) about a week ago. Confirmed not only that it was a coolant leak from the OFH gaskets, with fluids coming from top bottom left *and* right, but that a piece of the OFH plastic had broken off internally. It was nowhere to be found in the engine valley where all the dirt and gunk were; it either went somewhere into the OFH or the engine.

- Coolant leak is now resolved. For full detail including photos of the damage on the OFH, see a thread I had going over at the North American Motoring forum.

- To my knowledge the car has NOT had the coolant line replaced that was mentioned in prior posts in the thread about some sort of US/North America recall. That said, I would love to know exactly which hose it is so that I can examine it -- maybe it has a date code on it -- and replace it if it's original.

- Part for the B46 (11-42-8-585-235) is different from the B46 -- oil filter is positioned differently in particular -- but the general construction is about same.

Worth a mention: due to the underbody shield there was never much coolant on the floor. Didn't spot any until the day the climate control heating went cold. But after putting the front wheels on ramps, pulling the shield, and letting the car sit for a month... well, between my prior oil fill (topped off coolant) and a week ago, it dripped so much onto that shield and later onto my floor that the aux water pump and major hoses were almost completely dry. Just sitting idle for a month leaked a good amount onto the floor too, pre-repair. It kept leaking onto the floor right up until I installed the new OFH. The original OFH leak was no joke.

I also had an R56 S get me... "familiar with coolant issues associated with the use of these plastics" years ago, when I literally had a coolant tee tear (not crack, *tear*) in two in my hand while being pressed against doing an oil filter change. The vehicle was at about 141K miles but still, that was a new experience for sure.

So having these experiences, I am working out how/where/when to add replacing plastic and rubber coolant system components -- tees/attachment points and hoses, mostly, though at some point the water pump too -- as part of the maintenance schedule (I intend to have this F56 S for a very long time, if it will cooperate with me).

Anyway, hope this is useful to someone, and thanks for the discussion in this thread.

[x3sm]

Can a cracked OFH leak enough coolant to mix with oil and cause engine damage? What to watch for? Disappearing coolant?

[GOLDENDUSt86]

Originally Posted by x3sm

Can a cracked OFH leak enough coolant to mix with oil and cause engine damage? What to watch for? Disappearing coolant?

Unlikely to happen, however a defective oil cooler (which did above the OFH) would definitely cause oil/water to mix

[BRK]

b48 engine water issues. Here's one; location west australia.
Mate is finalising a deal on a 330i, 90,000 kilometres, from the local authorised dealer. One condition of the purchase was that the housing and coolant line be replaced as part of the pricing. Response was "Already done by us for the previous owner. Here are the records."
The ONLY way we found out about this matter was via the forum - thanks to all that posted.

[alexonahurry]

Originally Posted by GeorgeF31

I have not at any time disputed the facts of his situation or that problems can and will happen to the engines. Nor do I debate the need to discuss problems and whether they are prevalent or not.

I will continue to call out unsupported generalizations.

I wonder what GeorgeF31 might think after the last one and a half pages of this thread . . . .

[F36_Paul]

On my 18 430ix the expansion coolant line blew up literally while I was driving to the dealership. Engine started smoking and fortunately the timing was impeccable as it happened once I arrived. They replaced it under the recall but had this happened while I was driving elsewhere I would have been screwed. Car had 41k miles on it. Aside from this my valve cover has been leaking since 39k miles at least, and the car seems to have very inconsistent performance.

[GeorgeF31]

Originally Posted by alexonahurry

I wonder what GeorgeF31 might think after the last one and a half pages of this thread . . . .

I’d think it’s still a statistical error on the number of units in the field.

[Mr.Smartepants]

The B48 engine in my 2017 320i GT (F34) has been rock solid until this weekend when the coolant vent line blew the cylinder head connector off. The plastic connector inside the hose degraded and snapped off venting coolant all over the road. I replaced the line myself (BMW UK refused to honor the BMW North America recall).
Other than that, it's been running solid for 55k+ miles. I already changed the turbo charge pipe, ignition coils/plugs, and added a K&N filter to the OEM intake before having a local dyno shop do a stage 1 tune (amazing performance!)
Reading this thread has me considering ordering the valve cover gasket, oil filter housing/cooler assembly, water pump, and associated seals just to do preventative maintenance knowing the plastic in the vent line failed...the plastic oil filter/cooler housing won't be too far behind.
Would replacing the OEM rubber coolant hoses with silicone hoses be overkill? They're not cheap.