Suspect that the water pump on my '85 Cali-spec 300TD is starting to fail. No leaks, but shortly after start-up on colder mornings (low-40's) I will get a cyclic 'whirring'/rubbing sound which quiets within a mile as things warm up.

When I first heard it I though perhaps I had allowed the SLS pump to run dry, but the system is full and holding pressure just fine, no issues there.

I can feel a tiny amount of play in the fan blade, which may be attributable to the fan clutch itself.

I've tried to determine the location of the noise while driving, but as soon as I park the car at idle the noise is no longer present, Accellerating the engine via the linkage does not produce the sound either.

Shopping for a water pump presently, and there are multiple choices/manufacturers. Apart from the OEM M-B part ($$$$), are there any which are recommended, or to be avoided? I've seen the posts warning of straight vanes on the impeller and the like, but no specific recommendations.

Thanks in advance,
Dave

I'd just call PP and ask for their recommendation.

BTW, the best way to check that sucker is with a mechanic's stethoscope. Place it on the housing and you'll know pretty quickly. Not a bad thing to add to a regular service interval, just listen to all the rotating accessories for anything unusual. Use caution, of course, since you're working around a spinning engine.

Good luck.

I replaced mine with a Laso. Make sure the replacemenet has metal impellers.

__________________
85 300CD Signal Red/Tan sold
83 300D Manganese Brown 109K
97 E420 Midnight Blue 197K sold
98 BMW 328i Vert White 100K, sold
95 BMW 525i White 125K, sold
93 BMW 525iT Red 193K, sold
95 E320 Green Wagon 125K, sold
94 E320 White 127K, sold
85 300SD 156K Grey (Annie), sold
84 300D Lapis Blue 170K (Judy), sold
99 ML 320 Black (lease), 1998 C230 White (lease)
00 Honda S2000 Red (lease)
86 Mercedes 300E (sold)
84 Porsche 911 Red (sold), 1965 Porsche 911 White (sold)