Rotating smoothly ....

Hello all,

Just a quick question about my 2001 boxster 2.7- last night I got home and heard a funny noise from from of engine area. I suspect water pump is beginning to go. I removed the belt to check rotation on the pump. It goes around but not smoothly. I'm about 90% sure it's the culprit, all the other pulleys look ok. Can anyone confirm that with the belt off that the pump should rotate smoothly? Thanks...

this is my experience.

What I found was there some play present when I checked the water pump pulley/shaft though not much. I went around and tried all accessory drive pulleys/shafts and only by comparing their lack of play to the tiny amount of play the water pump pulley/shaft had was I comfortable the water pump pulley/shaft indeed has some play.

The serpentine belt gave me a clue, too, for the inner edge was sharp. It had been rubbing against something -- one of the shallow sides of one of the accessory drive pulleys -- and the water pump pulley showed signs of having some belt contact.

The other edge was dull/rounded and so were the two edges of the old belt (I had saved the old belt) which I had replaced not too long before with this new belt. This told me the water pump went from ok to 'bad' in a relatively short span of time, IIRC in just a couple of months if that long.

If your car engine's water pump turns with any roughness odds are it is in worse shape than my car's water pump. Are there significant signs of white residue on the pump casting? If this is present this is dried anti-freeze and another sign of water pump troubles.

When I had satisfied myself the engine water pump was highly suspect I arranged to have the car flat bedded to a dealer and the pump replaced. I didn't want to risk the pump failing while driving.

Thus my advise to you is to get a confirming diagnosis then do not delay in having this water pump replaced. I would avoid running the engine any.

Sincerely,

MarcW.

Thanks mark,

I suspected that was the issue, no play in the shaft yet and the original noise is intermittent but the water pump does not rotate smoothly at all. I've already parked the car and will pull the pump later today. No indication of any other damage short of a bit of wear on the belt edge. Likely I caught it very early, it pays to know the "feel" of a cars vibration.

Thanks...

... is a relative term.
It's not going to rotate like the alternator or an idler pulley.
The water pump pulley is attached to the impeller and when rotated, whether manually or with the belt, it will move coolant so it won't feel "smooth".
There shouldn't be rubbing or grinding noises.
Happy Boxstering,
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

any feel that I could attribute to the impeller turning.

I just turned the water pump by hand and not very fast at all.

The power steering pump had some roughness but I did attribute this to the fact I was turning a pump. I can't recall how the A/C compressor felt but I do not recall any roughness being present, which I guess makes sense for when I turned/spun it by hand the clutch was probably not engaged so I was just turning the pulley and not much else.

My bigger concern was detecting abnormal play and for this read any play. For this I had to go around and check all accessory drives finally coming to the conclusion while the play at the water pump was not that great, in fact barely noticeable -- and I like to think I have some residual skill/talent for this from my machinist days -- the water pump did have play while the other accessory drives had none.

Sincerely,

MarcW.

Pump is out, turns very stiff and intermittently smooth. Pretty sure I've got the culprit!

Thanks guys, I'll post when I pick up the new one and compare.

Confirmed,

The new pump turns smoothly and without resistance. I must have heard/ felt the first death rattle of the old pump.
Thanks again all. It's great to have a place to reach out and ask a silly question or two...

Hahahahahaha, whereas changing the pump was relatively easy, refilling and burping the coolant system was not. All seemed well at first, I followed the directions to the letter, test drove the car, temp seemed a bit higher than normal, got it back to the garage, and sure enough, excess pressure built up and sprung a leak on one of the lines...probably gonna spring for a shop to flush and fill for me...after I find the leaky hose and replace...

Stuttgart motors of Lexington was very gracious and helpful on making sure the coolant was replaced correctly. Well worth the 70.00 to make sure all was well. A quick trip thru ss tire for some new treads and I'm ready for a real road test.

Happy boxstering!



Edited 1 time(s). Last edit at 08/17/2012 05:03PM by Mstimely. (view changes)