New bearing noise -> water pump or pulleys?

[dtwinters]

I have a 2003 Boxster with 77,653 miles. I am the third owner and this Tiptronic Porsche was brand new in late December 2002. It is my daily driver and most of its miles are on the highway. It hasn't been tracked.

Roughly two weeks ago the coolant temperature blinking light came on for roughly a minute. It has come on once since then. Each time the engine temperature was perfectly fine throughout the 1 1/2 trip. I did not until today check the coolant level (my bad) and now see that the fluid is well below the minimum level but can be seen when looking down through the opening.

On the way home from San Antonio for Thanksgiving I heard a new cyclical noise that sounds like bearings going out. I've read up on different websites that it is likely my alternator, pulleys, or water pump. My battery registers 12.6 volts when the engine isn't running and 13.93 when it is running. I bought a mechanics stethoscope and as best I can tell the water pump and the lower pulley seem to have rough noises. And there does seems to be the smallest flutter in the water pump pulley with it going in and out maybe 1 to 2 mm.

Here's a link to a short video (

) of the engine running and you can hear what I think is a bearing going. Would the next step in isolating the problem be to remove the drive belt and try spinning the pulleys and water pump pulley freely to see if there is any obvious failure going on? I tried the WD-40 trick but spraying it on the pulleys while running didn't make any obvious difference.

If it is the pulley and/or water pump how difficult are those fixes if I'm handy and have in the past replaced a turbocharger on my old Saab 900? I don't fear much in the way of fixes (perhaps to a fault). Please share your wisdom or I'll end up spending too much at a shop. :-)

Thanks,

Trevor in Austin

[JFP in PA]

First, let me say that listening to sound clips has proven to be the least useful way to diagnose these problems. With both the quality and volume all over the place, it becomes very hard to discern any useful information. We have had customers email us sound clips, only to find something completely different from our analysis of the sound clip when the car arrived at the shop.

The best way to check out what is making the noise is to pull the cover behind the seats and remove the serpentine belt, then rotate each component looking for noise, wobble, or other signs of distress. Quite often, if the water pump is on the way out, you will find evidence of a slight leak from the vent hole under the pump as well.

Edited November 25, 2012 by JFP in PA

[dtwinters]

Thanks JFP! You nailed it. I looked under the water pump and sure enough there was the smallest amount of dried gunk where it would run down; nothing like what you have in your photo, but enough to confirm a leak. And sure enough, when I took the belt off I could sense the smallest amount of play in the water pump axle.

So, my next step is buying a new water pump and gasket. I am also considering a lower temp thermostat. I've read on this forum that non-OEM water pumps are a very bad idea. Are any of the water pumps listed on this Ebay page worth buying? Would Sunset Imports have OEM and a good aftermarket model available? Am I foolish to try to save a couple hundred dollars versus Porsche OEM? I hope to do the repair myself. Does anyone have a ball park on how many hours a dealership or indie shop is likely to charge?

Water pumps -> http://www.ebay.com/sch/i.html?_sacat=0&_from=R40&_nkw=boxster%20water%20%20pump&_sop=15

Here's one from Deutche Parts -> http://www.ebay.com/itm/Porsche-986-2-5-2-7-Boxster-Water-Pump-METAL-IMPELLER-/400180027238?pt=Motors_Car_Truck_Parts_Accessories&fits=Model%3ABoxster&hash=item5d2c969f66&vxp=mtr

Motorad low temp thermostat housing -> http://www.ebay.com/itm/250871925575?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

Thanks a million!!! I'm hoping to order parts tomorrow so I can get it replaced next weekend.

Regards,

Trevor in Austin

[JFP in PA]

We do not use anything but the OEM pumps; the aftermarket units have proven to be too unreliable. Sunset should be able to set you up with a good deal on the OEM unit, ask for Jeff in parts.

The lot temp thermostat is a great upgrade to do at the same time, we have use the LN Engineering version with great results.

[jdannucci]

Just did my water pump this past August. The sound in your video clip are exactly the sounds that I had before it completely failed.

I would call Sunset Porsche and deal with them.

I ordered new pump, gasket, and new thermostat with gasket for under $325 with shipping.