[tip_m]

I had an upper radiator hose that was leaking from the couplers and after replacing it now the “quick connect” that plugs into it and goes to the firewall is leaking

Does anyone know the P/N for it? It’s the one connected to #10 in the attached schematic. I’ve looked through realOEM under radiator and heater/air conditioning and I couldn’t find what I was looking for — very possible that I missed something obvious.. Many thanks.

[tip_m]

Here is where the leak is coming from. Upper radiator connecting to the radiator is dry. Also if anyone has any ideas on how to seal that w/o replacing the hose I’m all ears.. Thanks!

PS: apologies for large images, can’t seem to re-size.

[tip_m]

Found it: https://www.fcpeuro.com/products/bmw...or-64216983858

[StradaRedlands]

You'll need to replace the O-ring in the hose plugging into the bottom of it. It will be hard and flat at this point, but holding pressure as it gets fused onto the other piece. Once you break the seal by replacing the top hose, it's useless.

Hope you replaced the Mickey Mouse flange (#8) and the upper overflow hose (#15) while you were in the area!

[tip_m]

Yep, makes sense.. Luckily #8 and #15 are fairly new and seem to be holding up (hope I don’t jinx it!). That leaking hater core hose looks original to the car so long overdue for replacement and I ordered both heater core hoses from FCP.

[StradaRedlands]

Yeah, that's doing it right!

[lowrydr310]

Originally Posted by tip_m

Yep, makes sense.. Luckily #8 and #15 are fairly new and seem to be holding up (hope I don’t jinx it!). That leaking hater core hose looks original to the car so long overdue for replacement and I ordered both heater core hoses from FCP.

After a recent radiator and upper hose replacement, my heater hose quick connector is slightly leaking. Should have done it right the first time and replaced the o-ring at a minimum. However those heater hoses are shot, and when my car cools down they flatten. When hot they feel extremely soft.

[StradaRedlands]

Originally Posted by lowrydr310

After a recent radiator and upper hose replacement, my heater hose quick connector is slightly leaking. Should have done it right the first time and replaced the o-ring at a minimum. However those heater hoses are shot, and when my car cools down they flatten. When hot they feel extremely soft.

I've never checked mine... now you have me worried!

[335i54n]

^ its a Hot side coolant hose so pm is worth it but i had good luck just flipping the oring around. never seen it crumble like mickey but does turn brown but is the least likely to fail of the hot side hoses (1st-mickey, straw hose, upper, then heater)

[vxracer]

If you haven't swapped it out yet, I would also recommend swapping the plastic part that it connects to. With age, it can be very brittle and the nipple where the small hose runs across the top of the radiator, And possibly even the 1/4" sized plastic line with a metal one. I touched mine and it snapped off. Replaced both at the same time. At least, inspect it, but don't put pressure on it. Breaks very easily with age

[watchout-everyone]

Originally Posted by lowrydr310

After a recent radiator and upper hose replacement, my heater hose quick connector is slightly leaking. Should have done it right the first time and replaced the o-ring at a minimum. However those heater hoses are shot, and when my car cools down they flatten. When hot they feel extremely soft.

i am in same exact situation lol.

Will be changing the heater hose soon (changed O-ring two times but still leaking althought reduced noticeably). My dealership wanted $850 to replace it

good luck buddy

[watchout-everyone]

Originally Posted by 335i54n

^ its a Hot side coolant hose so pm is worth it but i had good luck just flipping the oring around. never seen it crumble like mickey but does turn brown but is the least likely to fail of the hot side hoses (1st-mickey, straw hose, upper, then heater)

Hi, so sorry but what is 'pm' your're referring to?

[lowrydr310]

Originally Posted by watchout-everyone

Hi, so sorry but what is 'pm' your're referring to?

Preventative Maintenance??? (replace before it fails?)

[crashoverride]

One of the biggest weaknesses on the e90 is the cooling system. its not "If" but "when" the hoses will fail. When in doubt or just have the opportunity always err on the side of replacing

[jsunma]

Just in case anyone stumbles over this thread in the future via a search, the hose you're referring to is commonly called the UPPER RADIATOR HOSE. This has nothing to do with the "heater core" (as you've found). There are two hoses that run to the heater core. One does connect to this upper radiator hose.

In RealOEM, the part numbers for those hoses that connect to the heater core ( versus the radiator...which I think you may be confusing terminology-wise with the heater core) are in the "Heater and Air Conditioning" section.

FWIW, the heater core hoses seldom fail. The upper radiator hose (which you are talking about here) does fail often in the ways that folks here are stating.

[tip_m]

In my case I had the upper radiator hose fail — was leaking at the connectors on both ends.. When I replaced it had to disconnect the heater core hose and that was the end of that connector too and while I had the coolant system open decided to replace both heater core hoses. Parts replaced from FCP were:
- BMW HVAC Heater Hose: BMW-64216983858
- BMW Heater Hose: FEB-101057
- BMW Radiator Hose aka upper radiator hose: CRP-CHR0405R

[Ghettobird52]

If you went with the Rein hose you referred to, CRP-CHR0405R, that could be your problem.

I just replaced the radiator and upper/lower hoses last night and hit the same issue. I put the rein hose on and the lower nipple on the upper rad hose leaked where it connected to the heater hose. It literally had wiggle room and water just came out on the bleed cycle, not even with the car running. I took it off and glanced at both original and the Rein hose, they are slightly different in size. With a caliper on hand, the rein is smaller by a fraction, which makes the fitting loose. I put the old one back on and boom, no leak. I was only replacing the hose preventatively as the rad was the only thing bad. I've never had any issues with a Rein product so didn't look closely at the reviews on FCP, but lo & behold other recent reviews note the exact same fitment issues. Seems like recent batch or change in production issues with things slipping past QC. It's possible yours was the heater hose, however I would go back out and see how the fitment is. If you have wiggle room on that hose/nipple its possible once that O-ring softens up, your gonna have the same leak appear. I'm sending the Rein hose back and will order genuine.

[tip_m]

Yeah I went with Rein since that’s what I had replaced with ~4 years ago and I can send the old one back to FCP for store credit. Fitment is tight and no leaks so far but will keep an eye out for sure — thanks for the suggestion…