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Is there a way to check if the water pump is on it's way out?

2K views 11 replies 8 participants last post by  Awake77 
#1 ·
So, continuing on with my big plenum-off tuneup and having gone down nearly all the 'while I'm in here' maintenance rabbit holes, I'm now at the point where I'm replacing the thermostat, and just pulled the housing.

My car is a 2001 and has 135,000 miles on it. I'm lucky enough to be the 2nd owner (since 120kmi), and I have a big book of service records - from what I can tell the water pump is original.

I'm going to change the drive belts & radiator hoses, and I'm tempted to go for the water pump too while i'm here, although I've never had a problem with it.

With the drive belts off, is there any way to 'test' the water pump's condition? Like will rotating the pulley by hand be a good indicator (if it feels like bearings are catching it should be replaced, etc)?

I'm thinking I'm going to save it for another time, as I'm sure I'll have this beast apart again before too long - but if there were a way to check it's condition I'd replace it now if I needed to.

Thanks,
Chris
 
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#2 ·
I don't think there is a way to check the water pump, besides rotating the impeller. That basically tells you the bearing is good if it rolls smoothly. The mechanical seal should be good if it has not leaked to this point, but when will it start leaking? That is the question.

If you don't have any long distance trips coming up, I would stick it back in.
 
#4 ·
Whoops. Just realized since replying to another of your posts that you already went down the rabbit hole!

For the water pump, you can try spinning it and listening for noises, slow turn it to feel the bearing, just as you would check any other bearing. They usually don't exhibit signs until very near the end of life. My original pump died around 130-140k. I can't remember the exact mileage. It started making noise and eventually the bearing complete **** the bed but unlike many, it didn't start puking coolant out the weep hole.

My advice is to buy an OE pump from BMW. That's what I did back then and it's still going after another 130-140k miles.

As for when you replace it, that's dependent on your wallet and time value. You can see how far in you need to go to access it. It's also not cheap. I think the OE pump is $300+.

Good luck!
 
#6 ·
Lol yes, the fuel injector thread! Thanks for the advice, I'd definitely go OEM should I replace the pump. I think I'll just check out the bearings and leave it for now, so i can get the car back together. Summer is already half over and I really don't have any big trips planned. I haven't driven the car in nearly 2 years - I am dying to get in that cockpit asap, but don't want to cut corners either.

My hope is that I can drive/enjoy the M for another 10kmi or so before replacing chain guides/rod bearings/etc whether they need it or not, that would be a fine time to replace the pump as well. If it goes before then, at least I can get there quickly now that I know what's involved.

Fan clutch is probably also in the end of it's lifetime. I think mine overloaded the waterpump to breakdown. The new fanclutch doesnt engage nearly as mutch as the old one.
Yes, mine was getting pretty noisy so I have a new one ready to go in when I put the car back together - thanks for the heads up!

-Chris
 
#7 ·
Dont listen to them!!

Inspect it for play in the axle. Its super easy to tell when most wp’s are on their way. If there is some play in the axle its no good.. just a tiny little bit is ok. But you shouldnt be able to wiggle it. Turning it by hand often wont tell you much as you cant apply the pressure like the belts do.. unless its really really bad you wont be able to hear anything abnormal turning it by hand. If you do, you wouldnt be able to hear the vanos noises wen the engine is running as the wp would drown it
 
#8 ·
At 130K miles, I would just replace.
But you can wiggle the shaft and see if there is any play.
 
#9 ·
On the subject of keeping our cooling system reliable, in addition to the water pump and hoses I just wanted to know if you guys are also replacing the heater control valve (part # 64118374994). My concern is that the body is made out of plastic, and I have seen first hand BMW plastic fitting fails in the cooling system. I figured that for reliability reasons (I plan to keep the car for a long time), probably makes sense to replace all plastic in the cooling system. Thoughts/opinions?
 
#10 ·
While I definitely go in and replace a lot of parts when doing projects because "while in there", I'd leave that alone.
I've been dealing with BMW plastic components for years and I've never heard that one failing.
There are probably few failures out there but is't definitely not in category of cracking radiators, expansion tanks etc...
 
#12 ·
Quick update:

Just got my belts off and the waterpump pulley feels OK. Tiniest bit of play - I can barely tell. Gonna get the thermostat back in today and keep going with my Beast restoration :D
 
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