[Niart906]

It should come as no surprise to anyone familiar with old BMWs, but their cooling systems were often less than reliable. I had hoped that with BMW's newest generation of cars that this was no longer the case. However, I recently had a small coolant hose break and send coolant all over my engine bay, this would have left me stranded had I not been parking the car in the garage after a wash.

The hose that failed was #2 in the diagram below. The plastic male barb snapped at the connection to the larger plastic quick connect.



The exposed plastic was very brittle so no surprise it broke when it did. My 2013 335i has just over 70k miles on it. I would strongly suggest anyone near my car's age/mileage to preventatively replace this hose. In general the N55 has been amazingly reliable when compared to BMW's prior efforts. So I'm hoping this is an isolated issue. It looks like BMW updated the part number for this hose, so maybe they've already created a fix. I'll compare the two when my new hose arrives tomorrow.

TLDR- Replace this $40 coolant hose on your high mileage 335 before it fails and leaves you stranded.

[Zanity]

Thanks for the heads up man.

[Framamind]

Yep, mine gave out on the way to work last week. 62k miles
Those smaller hoses are usually the first to go.

[SteelBlue46]

Had this hose break the exact same spot about a month ago! luckily very cheap from dealer and easy fix! I noticed my new hose was alot more flexible than the old one which was so brittle I grabbed it and it crumbled.

[perryo91]

Great PSA man, mine broke at around 40k, i stopped the second I saw steam then had to wait 3 hours for a tow but definitely recommend replacing it.

[Niart906]

Originally Posted by SteelBlue46

Had this hose break the exact same spot about a month ago! luckily very cheap from dealer and easy fix! I noticed my new hose was alot more flexible than the old one which was so brittle I grabbed it and it crumbled.

Interesting that the new hose was more flexible. Hopefully this part was revised so this won't be a repetitive issue in another 40-70k miles.

[chiefneil]

Thanks for the tip, and wow that is a clean engine bay for a 5-6 year old car!

[Eddien123]

already broke mine. The day I got it delivered to me actually. Have no fear though. Even from the dealer it was less than $40 and took me not even a minute to install.

[Polo08816]

Originally Posted by Niart906

It should come as no surprise to anyone familiar with old BMWs, but their cooling systems were often less than reliable. I had hoped that with BMW's newest generation of cars that this was no longer the case. However, I recently had a small coolant hose break and send coolant all over my engine bay, this would have left me stranded had I not been parking the car in the garage after a wash.

The hose that failed was #2 in the diagram below. The plastic male barb snapped at the connection to the larger plastic quick connect.



The exposed plastic was very brittle so no surprise it broke when it did. My 2013 335i has just over 70k miles on it. I would strongly suggest anyone near my car's age/mileage to preventatively replace this hose. In general the N55 has been amazingly reliable when compared to BMW's prior efforts. So I'm hoping this is an isolated issue. It looks like BMW updated the part number for this hose, so maybe they've already created a fix. I'll compare the two when my new hose arrives tomorrow.

TLDR- Replace this $40 coolant hose on your high mileage 335 before it fails and leaves you stranded.

This part broken on me when I was attempting to replace the accessory belt and belt tensioner. It broke at exactly the same place it did for you. It left my car stranded at APG for about a week. It was really easy to reinstall - took about 5 mins. And another 15 minutes to bleed the cooling system.

[Niart906]

Originally Posted by Polo08816

This part broken on me when I was attempting to replace the accessory belt and belt tensioner. It broke at exactly the same place it did for you. It left my car stranded at APG for about a week. It was really easy to reinstall - took about 5 mins. And another 15 minutes to bleed the cooling system.

Fortunately I caught it quickly and lost very little coolant, so I'm hoping I don't have to bleed the system.

For those wondering, this is how you bleed the cooling system on our cars. Stolen from another thread...

Originally Posted by humbertob

17. Remove the bleeding screw (black screw) from the overflow tank
18. Using 50/50 BMW Blue Coolant/Distilled Water fill the overflow tank slowly until the coolant starts to escape from the bleeding hole at the overflow tank
19. Re-attach the bleeding screw
20. Replace the overflow tank cap
21. start the ignition on the car, without starting the engine
22. select the hottest temp on the a/c unit
23. select the lowest fan speed on the a/c unit
24. push the accelerator down to the floor for 10 seconds
25. you'll start hearing that the water pump starts working, it's bleeding the coolant system for you
26. Wait for 12-13 minutes until the water pump completes the bleeding cycle

[Niart906]

UPDATE: Swapped in the new hose this morning and topped off the coolant. Didn't need to bleed the system luckily.

The new hose is a bit more flexible than the old one, but otherwise identical. Fingers crossed this one lasts a bit longer.

[Zanity]

Originally Posted by Niart906

UPDATE: Swapped in the new hose this morning and topped off the coolant. Didn't need to bleed the system luckily.

How can you tell if you need to bleed or not without driving it though ???

[Sea-Tac]

Good advice...thx

[Niart906]

Originally Posted by Zanity

How can you tell if you need to bleed or not without driving it though ???

It all depends on how much coolant you've lost, my reservoir was only slightly low prior to my top off. Had it been empty I would have done the bleed procedure before trying to drive anywhere.

After replacement just watch your temp gauge as the car warms up. It should get to it's normal temp range then stay there, any hotter and you need to bleed/top off coolant.

[atlguy]

Whats the updated part number?

[Niart906]

Use realoem.com or call your dealer. You can’t order the old part through the dealer anyways. It’s NLA.

[Mobster1983]

Glad to see this thread here. Had my car in for service a couple days ago and the dealer said this hose was brittle and needed to be replaced. They wanted over $300... Looks like I will just order the part and replace it myself.

[F32Fleet]

Originally Posted by Mobster1983

Glad to see this thread here. Had my car in for service a couple days ago and the dealer said this hose was brittle and needed to be replaced. They wanted over $300... Looks like I will just order the part and replace it myself.

That's horrible. Should be no more than $40 plus 1 hrs labor and a splash of coolant.

[Pray for Mojo]

My coolant overflow elbow broke when doing the pure inlet. Those plastic elbows are garbage, the washer fluid elbow on the underside of the hood also broke when closing the hood normally.

[samsont]

Mine broke back in May at the same exact spot. This is the part number I ordered:
17 12 8 570 061

[sickF30]

Another victim here a few months ago at 65k miles. Happened while I was in a McDonalds drive thru. hahaha

[_bdiddyb_]

Yup - mine broke last year at the reservoir end. The constant heat/cool caused the plastic to curled up touching the hood and actually prevented it from fully closing. POS snapped in 2 when I slightly pressed it down out of the way. The new part# has a wider curve preventing rubbing against car's frame.