Can we talk about water pump failures?

[Daily02]

Poll: Since the water pump is a sore spot for a 2002 what is the failure mechanism? Is a bearing failure? Does the casting break? It sounds like it can't handle much side loading from the belt. Thanks!

 

Regards

 

Dono

[Son of Marty]

The pump can live with a normal tension set on the belt, but they do wear out as all pumps will do the bearings can wear out or the seal can go dripping water I've never broke the housing.

[tech71]

Never really been a sore spot for me crept that one piece of pure craponium I encountered with a plastic impeller

 

[Einspritz]

I think it's budget parts using cheap seals.

Or way too tight on the fan belt, but your alternator bushings will probably go first.

 

Is 200K daily driver miles too short a service life on a BMW part?

[Daily02]

It's not a catastrophic failure then.  A better bearing would help if one can be sourced that fits, or does with minor modifications. A new pump with low tension on the belt sounds like a reasonable solution. 

[jimk]

Bearings are wimpy and if the belt is tightened with no more tension than what it takes to keep from slipping on the alternator, it will last a long time.  Bearings get loose then the water seal will begin to leak.

 

First pump on my car crapped at 30k, next one ran forever.

[Conserv]

Maybe water pumps are a sore spot among ‘02’s with 100K+ miles since the last water pump replacement.

 

Jim’s pump failure at 30K-miles is the first I’ve heard of at such an early stage. And that was obviously a factory-installed unit, given Jim’s original-owner status. I’ve owned a bunch of ‘02’s over the last 49 years and I’ve not had a water pump failure… yet. I have prophylactically replaced pumps, however, with engine overhauls. And I’d have to guess that the quality of units today could be less than the original quality.

 

Keep a spare new or rebuilt pump in your spare parts inventory — so you don’t have to worry about availability and supply chains — but I personally wouldn’t spend much time re-engineering a part that regularly lasts at least 100K miles. Most fifty-year-old cars have more pressing issues! 😉

 

Regards,

 

Steve

 

[AustrianVespaGuy]

I don't know this for fact, but my guess is age/condition of the alternator bushings actually have a lot of influence on this.  Not sure whether new urethane bushings with a tight belt or old worn bushings that allow bouncing around would be 'worse,' but I figure too much of either probably shortens the longevity.  New good bushings followed by proper belt tightness is my vote!

[AceAndrew]

I'll take problems that don't exist for $100, Alex. 

 

 

(Unless plastic impellers are now a thing?  Last I checked they weren't),

[Daily02]

A lot of great prospective here. Thank you for the responses. Even if the pump lasts for 30K miles that's 3 years of driving, and this is a documented worse case scenario. The real worry is the part going NLA after a failure. 

[TobyB]

In umpteen years of driving, racing, and taking apart 2002s,

 

I've never had a water pump give me trouble.

 

I'll see your $100, Andrew and raise you.

 

In any car, water pumps are a consumable- they used to last 5k, and 

then get re- sealed and re- bearing-ed.  Then seals got better, and 10k was reasonable.

Then WW2 happened, and afterwards, 25k was good.

Then the space race happened, and everything got a lot better.  50k.

Then the internet, and it all went to shit, except for water pumps, which now

regularly go 100k+, but since cars go farther than that, they still get replaced.

 

Since 2002s fall somewhere after WW2 but before the internet, I'd say 

that the 2002 water pump is a bit more durable than most.

 

One advantage that 'modern' cars like the E30 introduced was a coolant level

sensor.  After that showed up, 'problems' like water pumps became annoyances,

not tragedies.

 

Cars were WAY more maintenance- intensive before the imports arrived in the 60's.

(yes, we were importing cars before then, but have you ever had a Briddish car???)

 

t

has had far more rear hub failures...

[Daily02]

Hub failures. A new can of worms. My car is up on jack stands for this problem now. How often do they fail? 

 

Regards

 

Dono

[tech71]

1 hour ago, AceAndrew said:

 

(Unless plastic impellers are now a thing?  Last I checked they weren't),

I dont think so, that was years back. The cheapest possible pump I could source recently( Gates brand from China) has a steel impeller. Its installed in survivor, I expect it to outlast me.

[tech71]

18 minutes ago, Daily02 said:

Hub failures. A new can of worms. My car is up on jack stands for this problem now. How often do they fail? 

 

Every 18.6 years, count on it.

[Mike Self]

3 hours ago, Conserv said:

Jim’s pump failure at 30K-miles is the first I’ve heard of at such an early stage. And that was obviously a factory-installed unit, given Jim’s original-owner status.

A little water pump history on my '69, bought new.  The original pump failed at 37k--leaked like a sieve.  Replaced with another factory water pump:  failed at 74k (do the math--same number of miles).  Replaced with yet another pump--still a Graf but sourced from the local import auto parts emporium:  lasted well over 100k miles before finally succumbing to leaks.  So go figure. 

 

Apparently someone changed the internal design on the pumps, as I've consistently gotten 100K + miles on replacement pumps on both cars. Even the '73s original pump went over 100k miles before failing.

 

While you might malign French cars and engineering, the water pump on my '59 Renault has never been replaced, after 63 years, because it has a grease fitting--a short squirt every 5k miles keeps the bearings well lubricated.  Worn/wobbly bearings cause the carbon seal to leak, and there goes the water pump.  Too bad our BMW pumps didn't have a grease fitting...One of these days I'll take a derelict pump apart to see if one can be added...

 

mike