Do water pumps give a warning before they break?

[Jersey General]

I have had a periodic high squealing sound, which is becomming more persistent. It started in late December. Originally I thought it was the drive belt. However the sound remained after I replaced the belt. I was considering changing the water pump. I was going to order the high performance water pump, and the aluminum housing. Of course I would rather not spend the money until I have too. Also I don't want to waste my time changing a perfectly good part. Any thoughts?

[billb]

...it began leaking slightly, and was loose to the touch. On the other hand, it can do like the original pump did in my wife's '95 525i, and just break off completely on the way home from work, with no warning at all. If you're unsure, it takes about an hour and $100 to replace it versus killing a head gasket or cracking a head if it lets go on the highway...your call.

[Jersey General]

Good point!

[Kalevera]

How were the idlers when the belt was replaced?

If the pump is original, it's just plain old good maintenance to replace it.

best, whit

[Jersey General]

There wasn't any play in the pulleys, if that's what you mean?

[Kalevera]

It's not so much play. Idlers make noise when they go bad. Has to do more with feel and how the bearing rolls.

best, whit

[joshua43214]

Water pumps normaly leak as an early warning of bearing failure. intermitant sounds like you describe can be caused by a bad idler or tensioner and sometimes the bearings in the alternator can do the same. remove the belt and spin each pulley, a bad bearing will feel kinda like it sounds, they wont always be loose, use a stethescope if you have one to listen on the center bolt of each idler. A bad bearing will make a rumbling or growling sound, a slight ticking is normal. usualy the rear bearing gives out first on alternators and you can often see the rear bearing area discolored on the outside.

[1995 525i]

I have had a periodic high squealing sound, which is becomming more persistent. It started in late December. Originally I thought it was the drive belt. However the sound remained after I replaced the belt. I was considering changing the water pump. I was going to order the high performance water pump, and the aluminum housing. Of course I would rather not spend the money until I have too. Also I don't want to waste my time changing a perfectly good part. Any thoughts?

Mine gave me the warning of slowly leaking coolant. Also a trained ear (BillB) could tell the bearings were shot by listening to the car idle (with the hood up). So, if in doubt change it. It isn't expensive and isn't too hard to do.

Michael

[1995 525i]

Mine gave me the warning of slowly leaking coolant. Also a trained ear (BillB) could tell the bearings were shot by listening to the car idle (with the hood up). So, if in doubt change it. It isn't expensive and isn't too hard to do.

Michael

Here's my post on the install:
http://www.bimmer.info/forum/showthread.php?t=19283