Any super secret pro tips for changing the N52 water pump?

[02Pilot]

Going to do a preemptive change of the water pump and thermostat on my 128i tomorrow. I've got new OE parts including the single-use bolts, the Bentley manual (E9x, but close enough), and I've watched a couple videos, so I've got a pretty good idea what I'm dealing with. For those who have done this a million times, are there any little tricks that save time or knuckles, or things to look out for beyond the basics?

[dworthy]

Get ready to get a blue shower!

Bavauto has a very nice video on replacing those two items: https://www.youtube.com/watch?v=o-BpUzAemyQ Part 2 will be next in the line-up.

The best advice I can give would be have plenty of time, like an hour or two for this. On the bright side, bleeding is a breeze!

[02Pilot]

Well, it's done. Took more time than it should have, but then it's my first time under that car, and first time working on an N5x-series engine, so I don't feel too inept. The engineer who decided on the placement of the upper water pump mounting bolt is now on my own personal enemies list. That one bolt cost me quite a bit of time, including accidentally loosening the lower A/C compressor bolt (working on my back, by feel, trying to avoid getting too much coolant in my facial orifices, does not always end well). In any case, it's back together, bled, and test-driven with no leaks or overheating, so I'm hoping I don't need to curse that particular engineer's existence again for quite a while.

[bmwdirtracer]

Wow, sorry I missed the thread 'til now. Not that I would have been any help; the job is a beech. A wet nasty beech.

And Darin's OBVIOUSLY much better than I am at this....it takes me HOURS OF CURSING!

(Oh, a swivel 1/4" drive E-torx is my tool for those bolts)

[02Pilot]

Wow, sorry I missed the thread 'til now. Not that I would have been any help; the job is a beech. A wet nasty beech.

And Darin's OBVIOUSLY much better than I am at this....it takes me HOURS OF CURSING!

(Oh, a swivel 1/4" drive E-torx is my tool for those bolts)

Yeah, I found the experience quite unpleasant. Not IRS tax audit or TSA cavity search unpleasant, mind you, but not anything I'm looking forward to repeating.

I used a 3/8" with a universal and some extensions. It was sub-optimal. Hard to find an E12 in 1/4" drive. Those clip-on hose connections were not exactly conveniently arranged either. At least reassembly was relatively painless, and the auto-bleed procedure is handy.

EDIT: Just discovered that a ratcheting box end E-torx set (covers E6-E24) exists - I'm not sure if it would have helped with this job, but it seems like something I might need to have around.

[bmwdirtracer]

To take advantage of your thread: E12 and E10 are available in 1/4" drive, and also 1/4" drive universal (swivel) from the tool trucks: SnapOn, Mac, and Matco.

I consider these indispensable. For example, the N52 oil filter housing gasket: the book says 3+ hours, with these sockets, takes me an hour. With your new prize, my friend, you want these.

https://www.matcotools.com/catalog/p...CESS-STAR-SKT/

Doesn't it suck, though? $35 for one damned 1/4" drive socket ??? It sucks, until the second time you need it....then it's a crazy good bargain..... (I forget if the OFHG is E10 or E12, I have both in 1/4 drive universal) You also want ratcheting ring-end torx wrenches.

If you do the OFHG:
Do the heat exchanger gasket, if you have this on the same housing.
Do NOT unbolt the water hose that goes to the center of the head, unless you have one in hand. It does not survive removal. For removing the OFHG without removing this hose, you need the ratcheting ring-end wrench.

How's that serp-belt tensioner pulley? Belt fully on the pulley?

[02Pilot]

Geez, that's one expensive swivel socket. But as you say, price is relative to value, and for anyone working on these with any regularity, it seems a valuable tool to have. The box ends are easier and cheaper - I'll add those to the list as well. I really wish this Torx stuff was never dreamed up and built. I'm sure there are advantages, but it's more and more refreshing to work on my 2002 every time I do it.

Chris, I did the tensioner, idler pulley, and belt preemptively a week or two ago. The old stuff seemed fine - I suspect it may have been replaced at some point, but with no record of it, I decided to start my ownership with new parts. That, air and cabin filters, the water pump and thermostat, and brakes all around have been taken care of. Ideally I'll get the transmission and diff oils changed soon, but other than that I think I've got the maintenance up to date.

[bmwdirtracer]

And now, my friend, you have one of only three 1 series cars that's truly being well maintained!

Tools are an awful, and a wonderful, part of doing this for a living. From reading the news, I see that there are many people in the Country who are addicted to opiates. That's only because they haven't found the Tool addiction.

[02Pilot]

And now, my friend, you have one of only three 1 series cars that's truly being well maintained!

Tools are an awful, and a wonderful, part of doing this for a living. From reading the news, I see that there are many people in the Country who are addicted to opiates. That's only because they haven't found the Tool addiction.

Tool addiction is more insidious and probably more expensive.

In fairness, the previous owners of my little 128i seem to have been quite diligent about maintenance as well, as the folder of dealer receipts that came with it will attest, so I didn't have to do much to get it up to speed. It's an astonishingly clean car for its age and mileage, moreso considering the price I paid. I showed it to a friend who's a sales manager at a Land Rover/Jaguar dealership and knows his used car values - his assessment was simply: "you didn't buy this car, you stole it."

Of course that just means I have more money available for tools....