Water pump failure

On a long trip water pump failed at 53k mi. Engine overheated but shut down in time to prevent any damage. The failed pump has a plastic impeller, pressed onto a knurled shaft. When cool the pumps works fine. When it got to operating temp the heater wouldn't put out hot air. Pump replaced along with timing belt and tensioner at dealer in TN. the new pump also has a plastic impeller. I looked at a new pump when I got home and the impeller was metal and am told it costs $9.00 more than plastic type.Anyone had a premature failure of this type? What is the average mileage at failure? Was I lucky or what? PT warranty covered replacment.
Bob Schaefer
04 Jetta GLS TDI Ventectomy

Yes, the one in my Passat failed (40k) just before I purchased it from a fellow club member and was repaired under warranty.

Go buy a lottery ticket-you are lucky the pump didn't screw up the tb,then the engine.

The 04's had a metal water pump impeller and the dealer should have put in a metal replacement. If yours was truly plastic then VW screwed up when they built your car and used old inventory.

TW

The 04's had a metal water pump impeller and the dealer should have put in a metal replacement. If yours was truly plastic then VW screwed up when they built your car and used old inventory.

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I don't think this is true.

if i'm not mistaken, all the VW Water Pumps have a plastic impellor... the aftermarket ones are metal.

I have never seen an OE metal impeller. Plastic impellers falling of is (unfortunately) fairly common. The extra peace of mine is worth the extra $9 to me and my customers, though some claim that the metal impellers do not move coolant as well.

Thanks for the replies. Guru in my area says 30k is about average for a plastic impeller water pump. I will buy an after market pump with metal impeller and change it out asap.

Pump replaced along with timing belt and tensioner at dealer in TN.

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Two things:

One you took it to the dealer. Take out your pee-pee to be whacked by someone.

Second, did they replace any of the rollers or tensioner or torque to yield bolts when they replaced the belt and pump?

Metal Man said:

I don't think this is true.

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Alright, when I am wrong I will say so. I am wrong. I was fooled by the fact that my wife's 03 Beetle had a black colored water pump that sounded distinctly metal when struck with a metal object. Likewise all the 04 PDs I have done belts on have had the black colored impellars on them. This black impellar is also made of plastic. I now know this because I took a pair of Channelocks and broke one of them into pieces. Apparently VW changed the type of plastic used in the water pumps (pink to black) at some point and I mistook it for a change to metal. I suspect the plastic that is black may be Kynar (PVDF) although I do not have verification of this yet. I am going to run a DSC (Differintial Scanning Caliorimeter) test on that plastic which will identify what the material actually is. I will also run a DSC on the pink plastic and when I get the results, I will post them to this thread. Crow is hard to swallow but I am trying.

Thanks Dennis.

Landon

TurbineWhine said:

Crow is hard to swallow but I am trying.

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You're worried about your image on a little goofup like that ? Get a grip, this is the intronet.

Water Pump

Bob Schaefer said:

Thanks for the replies. Guru in my area says 30k is about average for a plastic impeller water pump. I will buy an after market pump with metal impeller and change it out asap.

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Your Guru has been drinking antifreeze. If this was true there would have been a recall on all VWs. Many last up to 100K TB change! Oh and remember when you change that water pump you will also have to do timing belt. Approx cost for you paranoid $1000!

__. Hey, Bob. Welcome to TDIClub. When I had the timing belt and water pump replaced on my '02 sedan at about 88K miles, the plastic impeller was still pumping fine but when we took it out, it was badly eroded on all the vanes. There was no sign of looseness on the shaft (which seems to be the most common failure mode) but I was sure glad that that thing was coming out of there.

__. I always replace with metal impeller water pumps.

I've seen many more plastic impellers fail on gas motors than on diesel, well I've never seen one fail on a diesel. I'm guessing the lower temps of a diesel don't make them as brittle.

Metal Man said:

I've seen many more plastic impellers fail on gas motors than on diesel, well I've never seen one fail on a diesel. I'm guessing the lower temps of a diesel don't make them as brittle.

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That sounds logical. I have only seen 1 failure in Diesel and it was a 2000 Golf. The impellar had turned loose from the shaft and it would cool fine at idle but overheat the instant it was driven. The timing belt was way over limit at 125000 on the original belt. The car did not have an intercooler (wrecked), ran like a dog and the TB was literally shredded. When I tried to bar the engine to TDC with the cam sprocket, the TB belt slipped. I told the owner to run buy a lottery ticket and get me one too, because he was undoubtedly the luckiest man I know.

TW