PSA: Replace this hose during a cooling system overhaul!

[HyeWarrior]

So over the past week, I've tackled a project with my N55. In particular, installing a new intercooler, new charge pipe, replacing both OFHG, and attempting to install an aluminum radiator (didn't end up installing due to transmission cooling lines getting in the way).

After getting the car put back together, I noticed a severe coolant leak. It may have been leaking for months for all I know, and it may have been leaking on to my belt. Upon inspection, I found the culprit. Hose with part #11537584549. It connects from the thermostat, to the block, right underneath the oil filter housing. As you can see in the photo attached below, the plastic has completely withered away, separating in two. The O-ring was stuck in the aluminum insert point on the block, and took some effort to pry out.

I STRONGLY suggest replacing this hose when (not if), you replace your water pump. Reason being, this hose attaches to the back end of the thermostat, which sits behind the water pump.

Mind you, I discovered this issue after spending hours on the car, removing everything including the intake manifold to replace the oil filter housing gaskets. Unless you have the smallest hands in the world, you WILL struggle fishing the hose to the back of the thermostat, and struggle even more getting it securely in place. As far as I can tell, the only way to easily and effectively install with peace of mind is to drop the sway bar, drain the coolant, remove the water pump, remove the thermostat, and THEN install the hose properly.

The reason I bring this up is because I've spent nearly 3 years on this forum, and I have never seen anyone mention this hose needing replacement. It wasn't until I discovered the problem and did a google search that I found one thread mentioning this hose.

Again, I STRONGLY suggest you replace this hose when it comes time to do your water pump. Online prices hover around $65, I found it at a dealership about 45 minutes away for $85 with tax (and O-ring included), most other dealerships wanted $120+.

[icegrill]

Is this the same for N54s?

[KNS]

What fun. Thanks for the heads up on that.

[Mototrav22]

How many miles are on your car?

[1and1]

Originally Posted by icegrill

Is this the same for N54s?

Same issue, connection to engine under OFHG is the same. Part number is different
N55- 11537584549
N54- 11537541992

Not sure how different it really is, but there ya go.

FWIW, N54 OE BMW is ~$70 from ECS, or they have Rein version for ~$25 which is probably fine.

Still a bitch to attach to the thermostat tho. Certainly a worthy add to a water pump job, and wish I had for mine...

[HyeWarrior]

Originally Posted by Mototrav22

How many miles are on your car?

2012 with 78k miles

Originally Posted by 1and1

Same issue, connection to engine under OFHG is the same. Part number is different
N55- 11537584549
N54- 11537541992

Not sure how different it really is, but there ya go.

FWIW, N54 OE BMW is ~$70 from ECS, or they have Rein version for ~$25 which is probably fine.

Still a bitch to attach to the thermostat tho. Certainly a worthy add to a water pump job, and wish I had for mine...

Thanks for adding the part number for N54's!

[iminhell1]

I'll just leave this here,


http://www.bm-parts.com/index.php?ro...&product_id=58

[1and1]

Well now,.... That's about a little bit of awesome right there
Thanks!

Ordered one.

[1and1]

Got the adapter in today's mail. Darn fine looking piece, smaller than I expected, and came with a new o-ring which is a nice touch.

Question: can this upgraded adapter be installed without removing the cooler lines?

[HyeWarrior]

Originally Posted by 1and1

Got the adapter in today's mail. Darn fine looking piece, smaller than I expected, and came with a new o-ring which is a nice touch.

Question: can this upgraded adapter be installed without removing the cooler lines?

For the N55, you just need to take out the fan, which isn't hard to do at all. I assume the N54 should be similar as well!

I'm planning on getting this piece down the road as well lol

[indy135]

HyeWarrior and 1and1

I ordered this part today too, because I putting my car back together and have the exact same problem.

Just wondering how you removed the old flange, and/or cut the factory clamp.

Thanks!

[1and1]

I haven't installed the new part yet, maybe HyeWarrior can help?

[oneBIGtoe]

Wish I had seen this before doing pump and thermostat. Such a pita!

[lab_rat]

Originally Posted by indy135

HyeWarrior and 1and1

I ordered this part today too, because I putting my car back together and have the exact same problem.

Just wondering how you removed the old flange, and/or cut the factory clamp.

Thanks!

Definitely interested on the install details as well...I plan to replace the water pump and thermostat in the next few weeks.

[Suprgnat]

Originally Posted by indy135

HyeWarrior and 1and1

I ordered this part today too, because I putting my car back together and have the exact same problem.

Just wondering how you removed the old flange, and/or cut the factory clamp.

Thanks!

If the old flange is brittle enough, just bust it up and take it out. Just don't drop any down the hose if you still have it attached at the bottom end.

[Suprgnat]

Originally Posted by iminhell1

I'll just leave this here,


http://www.bm-parts.com/index.php?ro...&product_id=58

$12.99

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[1and1]

Probably no difference between my fancy anodized black version for $25 and that nice plain aluminum version for $13. No matter what, I can't think of a 135 in existence that couldn't use one- this design is so much better than the OE plastic.

Install can be as easy as snipping the OE clamp, swapping & tightening a new, decent, hose clamp. Me, I ended up cutting the OE hose and being happy it was j u s t long enough to still reach.

Your mileage(hose stretch) can & will vary...

[Suprgnat]

Originally Posted by 1and1

Probably no difference between my fancy anodized black version for $25 and that nice plain aluminum version for $13. No matter what, I can't think of a 135 in existence that couldn't use one- this design is so much better than the OE plastic.

Install can be as easy as snipping the OE clamp, swapping & tightening a new, decent, hose clamp. Me, I ended up cutting the OE hose and being happy it was j u s t long enough to still reach.

Your mileage(hose stretch) can & will vary...

Yeah, it's just a chunk of aluminum. FWIW, black is around $15. My hose was/is still in great shape, but I have one of theses sitting in a drawer. Waiting.

[1and1]

Originally Posted by Suprgnat

...Waiting...

((pokes with random nearby stick --->poke >poke >poke ))




.

[dtla1]

I wonder why that amazon link, and all the other ones for this part all say for "next generation N55"?

[1and1]

It's actually the same part, no worries


.

[oneBIGtoe]

Will be installing mine this weekend. I got a Rein all aluminum version. Hoping that clamp comes off without any issues.