[ENINTY]

So I after 149,521 glorious miles, the water pump in my 325i died. I figured I’d do a DIY for it using the basic procedure for a coolant change (I wrote a few years ago). Also, I replaced the thermostat a few months back so I’ll throw that in too since you need to remove it to get the pump out. I don’t take pictures because it takes to long and I don’t want to dirty up my nice camera. The intent of my DIYs is to provide the details of removing parts by being descriptive enough that pictures are not necessary. I find that repair manuals lack the detail of how to actually remove parts and disconnect hoses and electrical connectors, which is what I try to add. They have good pictures though.

It's long and wordy, so I've just included the MS Word document to download and print.

Note: In the maintenace section JamesUKE92 did this procedure and included pictures. I used his efforts as a guide when installing my pump last weekend. JamesUKE92 was the first memebr I saw who attempted the T-Stat and pump replacement. Kudos to James!

[syl2us]

Anyone done this without draining the system completely just to change the thermostat itself or the Engine Coolant Temperature (ECT) sensor?

Car through P0128 code, thermostat malfunction, and needs to be fixed in order to stop Service Engine light from reoccuring. Reference my post here for more details: Service Engine Soon P0128

If so, please provide some details/insight and Part #'s (can't find them anywhere) if you can and any pictures if possible too! TIA.

[queensfield]

Originally Posted by syl2us

If so, please provide some details/insight and Part #'s (can't find them anywhere) if you can and any pictures if possible too! TIA.

Part number 11537549476 at realoem ($118)
It's under engine->engine cooling (http://www.realoem.com/bmw/showparts...54&hg=11&fg=35)

Coolant does have to be drained to replace thermostat. Also, don't forget the replacement bolts.

Great DIY from Eninty- this one and coolant as well

[07335ibmrblack]

this thread was very informative. I used it exactly on my 335i. except you need to take the intercooler out to drain radiator. no big deal. 2 torx bolts and 2 quick clips for the piping. thank you for the help

[pizzaflyer]

Thanks. Great writeup. Looks like our 330i needs a new pump. Who did you use for parts?

[ENINTY]

Originally Posted by pizzaflyer

Thanks. Great writeup. Looks like our 330i needs a new pump. Who did you use for parts?

Tischer.

[i M HOONIGAN]

I'm at 120K miles, and it seems my water pump is dead... I'll be posting details on the cost, what needs to be replaced, etc.

[Nsx_moda]

might have to do this one day,tag for later

[totalloss]

If anyone's interesting in how mapped thermostatic systems work, I found this. It's a good primer to show how the various engine load/engine speed/incoming air temp/vehicle speed combinations play into how the ECU pulses the heating element inside our thermostats. These combination values are compared to a stored map, thus explaining the term "mapped thermostat." Enjoy.... http://www.volkspage.net/technik/ssp/ssp/SSP_222.pdf

[Winkdinkerson]

Thanks to Entity for the DIY. I did the waterpump and thermostat on a 2010 328i LCI auto with 70K miles. It really is a bear - took me over 8 hours (without breaks), with car on stands.

I removed the passenger side wheel well cover and the electric fan. That really helped - the location of the pump and T-stat is so cramped that any extra space for maneuvering was welcome . Unlike most posters, I removed the water pump first, although I had to disconnect the large hose from the radiator to the thermostat in order to get at the infamous 3rd bolt on the water pump which faces the front of the car. I was able to remove the 3rd bolt using a stubby 3/8 ratchet and a universal extension.

I could not figure out how to remove the T-stat before the water pump, because one of the hose clamps on the T-stat was impossible to get at either from topside or underneath without removing the water pump first to gain access. However,when I started putting things back in, I connected two of the hoses on the T-stat first, then installed the water pump, then bolted the T-stat to the pump and finished the hose connections.

A flexible hose clamp driver REALLY helps, because of the awkward location of those hose clamp bolts. The hose clamp bolts seem to be 6mm, so any flexible driver with a 1/4 inch or 6 mm socket works. Another helpful hint is that when re-attaching the hose fittings with the U-shaped spring clips, keep the clips in the closed position, then push the fittings together (after properly orienting them) until you hear a "click." That will ensure a proper seal.

On my old e46, I replaced the water pump, T-stat, upper and lower radiator hoses, AND the expansion tank in much less time (about 3 hrs) than in this e90. Spent a lot of time cursing the new design.

[bsmoov]

After you do it once, it's easy. The first time I did it, I took my time over 2 days.

Then my car got rear ended and it was a total loss...

I bought a new car that needed a waterpump and thermostat so I removed the freshly installed parts on my totaled car, removed the parts on my new car, and installed the parts I took off of my old car onto my new car.

3x. In less than 1/2 a day. Take that!!!

[The Nightman]

Sorry to bump an old thread but I thought I would share my experience for future readers.

I replaced my water pump and thermostat on my 2009 328i AT with 70k miles as preventative maintenance. I did it at home on jack stands in ~5 hours. It's not a complicated job but the process is made difficult by poor access to the thermostat hose clamps and upper WP bolt.

I removed the front passenger wheel and sway bar completely to give myself more space. I did not have to remove the radiator fan but it might give you more access to the upper WP bolt.

I drained as much coolant as possible from the radiator before I began but there is still quite a bit of coolant trapped in the WP and thermostat hoses.

I removed the U hose first, then the thermostat and the WP last. The thermostat hoses are a huge pain and I actually found it easier to remove the forward facing hoses from the engine bay (after moving the reservoir hose out of the way). Silicone spray helps a lot with the removal of the hoses, including the clip ones.

I reinstalled the thermostat first, then the WP and the U hose last. Installation is much easier since you can orientate the hose clamps for better access. My car took just under two gallons of coolant and I did the bleeding process three times for good measure (with a trickle charger connected to the jumping points).

I bought a Pierburg pump (included the 3 bolts) and a Wahler thermostat (came in a Behr box) and they were exactly the same as the original factory parts. The original and replacement parts have date markings so you can verify their age.

The DIY here, along with the following resources, were helpful:
http://www.pelicanparts.com/techarti...eplacement.htm

https://blog.bavauto.com/14581/bmw-h...55-6-cylinder/

Good luck!

[ro881e]

Originally Posted by ENINTY

So I after 149,521 glorious miles, the water pump in my 325i died. I figured I’d do a DIY for it using the basic procedure for a coolant change (I wrote a few years ago). Also, I replaced the thermostat a few months back so I’ll throw that in too since you need to remove it to get the pump out. I don’t take pictures because it takes to long and I don’t want to dirty up my nice camera. The intent of my DIYs is to provide the details of removing parts by being descriptive enough that pictures are not necessary. I find that repair manuals lack the detail of how to actually remove parts and disconnect hoses and electrical connectors, which is what I try to add. They have good pictures though.

It's long and wordy, so I've just included the MS Word document to download and print.

Note: In the maintenace section JamesUKE92 did this procedure and included pictures. I used his efforts as a guide when installing my pump last weekend. JamesUKE92 was the first memebr I saw who attempted the T-Stat and pump replacement. Kudos to James!

Thanks to OP for the guide, I had recurrent codes for pump Comms and decided to take the plunge whilst the 330i was off the road during lockdown.

Reinstall is about 100x easier and faster than removal, but running like a dream now. Managed to source pierburg pump and behr mahle thermostat for £300 all in off eBay.

Having put this off for ages thinking it was really difficult I wish I had done it sooner. All in about 5hrs, including having to grind off and drill out one of the rad shield bolts which had rusted into oblivion. I also got monumentally stuck trying to get to two of the hose clamps on the back of the thermostat.

Thanks again! For anyone else thinking this is hard or expensive, dont! Just go for it, and use these instructions to a tee

[Jesda]

Just wanted to say thanks for providing the Word doc with details!

[Mcnelly]

Does anyone know the electrical readings on the pump

[Mosaud1998]

Originally Posted by freedomfries

Sorry to bump an old thread but I thought I would share my experience for future readers.

I replaced my water pump and thermostat on my 2009 328i AT with 70k miles as preventative maintenance. I did it at home on jack stands in ~5 hours. It's not a complicated job but the process is made difficult by poor access to the thermostat hose clamps and upper WP bolt.

I removed the front passenger wheel and sway bar completely to give myself more space. I did not have to remove the radiator fan but it might give you more access to the upper WP bolt.

I drained as much coolant as possible from the radiator before I began but there is still quite a bit of coolant trapped in the WP and thermostat hoses.

I removed the U hose first, then the thermostat and the WP last. The thermostat hoses are a huge pain and I actually found it easier to remove the forward facing hoses from the engine bay (after moving the reservoir hose out of the way). Silicone spray helps a lot with the removal of the hoses, including the clip ones.

I reinstalled the thermostat first, then the WP and the U hose last. Installation is much easier since you can orientate the hose clamps for better access. My car took just under two gallons of coolant and I did the bleeding process three times for good measure (with a trickle charger connected to the jumping points).

I bought a Pierburg pump (included the 3 bolts) and a Wahler thermostat (came in a Behr box) and they were exactly the same as the original factory parts. The original and replacement parts have date markings so you can verify their age.

The DIY here, along with the following resources, were helpful:
http://www.pelicanparts.com/techarti...eplacement.htm

https://blog.bavauto.com/14581/bmw-h...55-6-cylinder/

Good luck!

Replacing the after pump and thermostat look so easy in the videos. But, once you actually got to tackle the job, man is it some bs

My E90 AWD is at 72k miles rn. There are no codes or anything for the water pump so I think I'll hold out on that job. But, when it does fail, I think I'll pay my idny $670 to change it instead of DIY and spending weeks changing it out myself.

Unless its summer vacation and I'm off of college.

[Danny_j]

Great video and instructions Mosaud1998 ... Thanks Dan

[Danny_j]

Does this sound like the electric water pump?

https://www.youtube.com/watch?v=_mQfSOMmvUw

Thanks for your help guys. The videos are excellent !

Cheers
Dan

[whyzee125]

Water pump is not bad at all on a rwd. I did it on my n55 6 speed rwd last year and it was honestly much easier than I've always read. I was dreading it but I'd say it took me 3.5 hours start to finish and really nothing got me hung up, there's just a few things that need to be removed.

[Socal_R8]

great thread....

My sons 2008 328i n51 with 130k just lost the water pump and blew out the radiator ...

So I rented a u-haul truck and auto transport and went and picked it up from the shop that AAA towed it to...Irvine Motor Werks, Jon was great and didn't charge me anything for inspect and diagnose...I just couldnt justify the minimum $2K estimate on a $4-5k car, so I towed it to my father in laws house who has a lift and will tackle it myself....



ordered CSF radiator, water pump and thermostat and researching as much as possible while I wait for the parts to arrive.

Was going to go over on Sunday and remove the rad,wp and t-stat to get a head start while I wait for the parts that are expected Tuesday from Carparts.com, which had the best pprices and fastest shipping...

Sounds like I should start with the radiator then the wp and then the t-stat?

sounds like some universal E12 and E14 torx will be needed along with some extensions for the impact


wish me luck

[Grease23]

Don't go cheapo on the parts for the pump and thermostat. Unless you want to be doing this a second time.

[Socal_R8]

Originally Posted by Grease23

Don't go cheapo on the parts for the pump and thermostat. Unless you want to be doing this a second time.

honestly just want to get it up and running again....car has been a money pit since we got it for him few years ago. Luckily only paid $5K with 105k miles from a friend back in 2022, but this is like the 3rd issue we've had with it... It needs bunch of other stuff soon like motor mounts, brakes pads, etc ... just gonna try to trade it in for something newer and more reliable.