Should I replace the water pump?

oranga · 05-17-2021, 12:48 PM

2015 335i, 66k miles on the clock. The accessory belt tensioner is wobbling so I'm planning on replacing it. And i figure i might as well tackle the mickey mouse ears + coolant hose while i'm in there. If i'm doing that coolant hose, i'll need to drain the coolant right? And if i'm doing a coolant flush, i was wondering if i should replace the water pump while I'm at it.

I read somewhere it should be replaced before 100k mi, but haven't seen much mention of it here on the forums.

Thoughts? Should I replace the water pump as a preventative measure? Or do i probably have some time to go on it?

Polo08816 · 05-17-2021, 01:44 PM

You have some time on it. It's not the same water pump used on the X3 N55i.

frchdragon · 05-17-2021, 01:46 PM

If your original pump and thermostat last until 100,000 miles, you are on borrowed time.
So you might want to consider changing them if you are doing a coolant drain.

I am not familiar with the mickey mouse ears... Which coolant hose are you talking about, the thin one on top of the rad? You can change it without draining coolant as it is the top part of the engine, you won't lose much and you can fill and burp.

thejeremyman9 · 05-17-2021, 02:25 PM

Quote:

Originally Posted by frchdragon

I am not familiar with the mickey mouse ears... Which coolant hose are you talking about, the thin one on top of the rad? You can change it without draining coolant as it is the top part of the engine, you won't lose much and you can fill and burp.

No, mickey mouse flange is different

https://f30.bimmerpost.com/forums/sh...1547622&page=7

oranga · 05-17-2021, 02:46 PM

Sorry, the mickey mouse flange is this guy: https://www.turnermotorsport.com/p-5...tlet-hose-kit/

It is the flange and hose that goes from the OFHG to the thermostat/pump.

I know i can replace JUST the flange and re-use the hose without doing a whole coolant drain, but I imagine if i disconnect the hose at the thermostat without draining the coolant, i'll just make a huge mess.

frchdragon · 05-17-2021, 03:25 PM

Quote:

Originally Posted by oranga

Sorry, the mickey mouse flange is this guy: https://www.turnermotorsport.com/p-5...tlet-hose-kit/

It is the flange and hose that goes from the OFHG to the thermostat/pump.

I know i can replace JUST the flange and re-use the hose without doing a whole coolant drain, but I imagine if i disconnect the hose at the thermostat without draining the coolant, i'll just make a huge mess.

Thanks, I didn't know this stupid plastic piece had a name. Kinda makes sense, mine was super brittle when I did the OFHG and I replaced it without changing the hose. I did change the coolant hose where the OFH was leaking oil onto.

F32Fleet · 05-25-2021, 06:13 AM

I would wait.

123Britt · 05-25-2021, 07:18 AM

My 2015 N55 has approx 70k and I can't see keeping it beyond 2026 or another 6 years. So I believe I am at half life now.

So why not change here at 70K.

I just completed a refresh on mine -- simple to change.

05-17-2021, 12:48 PM	#1
oranga Second Lieutenant 87 Rep 221 Posts Drives: 335 6mt Join Date: Feb 2018 Location: Houston iTrader: (4)	Should I replace the water pump? 2015 335i, 66k miles on the clock. The accessory belt tensioner is wobbling so I'm planning on replacing it. And i figure i might as well tackle the mickey mouse ears + coolant hose while i'm in there. If i'm doing that coolant hose, i'll need to drain the coolant right? And if i'm doing a coolant flush, i was wondering if i should replace the water pump while I'm at it. I read somewhere it should be replaced before 100k mi, but haven't seen much mention of it here on the forums. Thoughts? Should I replace the water pump as a preventative measure? Or do i probably have some time to go on it?
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05-17-2021, 01:44 PM	#2
Polo08816 Brigadier General 1610 Rep 3,947 Posts Drives: 2014 335i M Sport Join Date: Sep 2010 Location: MD iTrader: (0)	You have some time on it. It's not the same water pump used on the X3 N55i.
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05-17-2021, 01:46 PM	#3
frchdragon Lieutenant 338 Rep 417 Posts Drives: 2016 BMW M4 Join Date: Feb 2021 Location: ON, Canada iTrader: (0)	If your original pump and thermostat last until 100,000 miles, you are on borrowed time. So you might want to consider changing them if you are doing a coolant drain. I am not familiar with the mickey mouse ears... Which coolant hose are you talking about, the thin one on top of the rad? You can change it without draining coolant as it is the top part of the engine, you won't lose much and you can fill and burp. __________________ '16 M4 bone stock '13 335ix Msport BM3 stage1 - MAD FMI - FTP CP - Bilstein B4 (SOLD) '85 635csi M30 turbo race car (SOLD)
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05-17-2021, 02:46 PM	#5
oranga Second Lieutenant 87 Rep 221 Posts Drives: 335 6mt Join Date: Feb 2018 Location: Houston iTrader: (4)	Sorry, the mickey mouse flange is this guy: https://www.turnermotorsport.com/p-5...tlet-hose-kit/ It is the flange and hose that goes from the OFHG to the thermostat/pump. I know i can replace JUST the flange and re-use the hose without doing a whole coolant drain, but I imagine if i disconnect the hose at the thermostat without draining the coolant, i'll just make a huge mess.
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05-25-2021, 06:13 AM	#7
F32Fleet Lieutenant General 3570 Rep 10,351 Posts Drives: 2015 435i Join Date: May 2005 Location: Southeastern US iTrader: (0)	I would wait. __________________ "Drive more, worry less. " 435i, MPPK, MPE, M-Sport Line
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05-25-2021, 07:18 AM	#8
123Britt Captain 289 Rep 864 Posts Drives: 15 M235i AT Join Date: May 2008 Location: Madison, Alabama iTrader: (0)	70-100K is Normal Change Interval WP/Thermo My 2015 N55 has approx 70k and I can't see keeping it beyond 2026 or another 6 years. So I believe I am at half life now. So why not change here at 70K. I just completed a refresh on mine -- simple to change.
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