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Old 01-19-2012, 02:01 PM
dkindig dkindig is offline
Officially Welcomed to the 'Fest
Location: Murphy, NC
Join Date: Nov 2009
Posts: 314
Mein Auto: '01 Z3 3.0i Roadster
Water pump weeping at 68,000 miles...

I hadn't seen this thread until today when it was revived, but I just discovered that mine was weeping yesterday at 68K miles.

I have been chasing down a very slight coolant loss for a couple of years now, replaced a leaking expansion tank cap and a thermostat that was leaking and not allowing the car to warm up completely (electronic, leaking at the connector) when I first got the car at 48K.

I kept having to add a very slight amount of coolant every 3-4 months and for the life of me couldn't find the source of the leak. Finally smelled coolant at the front of the engine after a run yesterday and it finally leaked enough for me to pinpoint it to the water pump bearing based on the white film around the area.

Because this is a common occurence I religiously check the fan for wobble whenever I'm fooling around under the hood and it is still very solid, no play at all. Lucklily I was planning a coolant change this week anyway and I have a new pump on hand since I was expecting this sooner or later.

Moral of the story: Make stock water pump replacement a standard 60K maintenance item, and I'm thinking that 90K will be my interval for radiator, expansion tank and hose replacement unless it rears its head sooner.

ETA: Fan nut was on VERY tightly, cracked the pulley trying to remove it by wedging a screwdriver between the pulley bolts, too much flex in the screwdriver shaft to work effectively, fabricated a pulley holder and got it off after 3-4 sharp whacks with a hammer, replaced with an aluminum pulley from eBay ($28 shipped). My OEM pump had the metal impeller. That model pump has a reputation for pump bearings wearing quickly and I did find a slight amount of play in the bearings once I had the fan off, replaced with OEM pump w/composite impeller. Had a noisy belt tensioner bearing as well so replaced the tensioners and belts while I was in there.

Last edited by dkindig; 01-31-2012 at 07:26 AM. Reason: ETA post-mortem details...
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