: Water pump pulley disintegrating
08-26-08, 09:36 PM
1997 Concours water pump pulley is looking as if it is melting and clumps of the material are being found in the surrounding area. Even being lodged in between the water pump belt and the tensioner. This explains the squeeking this past week. Now the tensioner pulley has a flat spot worn in it.
Is this part failure common? Or should I just chalk it up to the age of the vehicle?
You mean the drive pulley - the one on the camshaft? That one is plastic - I guess it disintegrate, but I sure never heard of it. The one on the pump itself is metal, I think
Check your pulley's. Sounds like one of the bearings is seizing and causing the belt to slip, thus melting the plastic pulley.
08-27-08, 11:09 AM
Yes. I do mean the drive pulley. It just seems odd that it would do something like this. I would understand if it cracked, but not just come apart in chunks.
08-27-08, 12:16 PM
Sounds like the tensioner idler seized, causing the belt to radically overheat from sliding over the flat pulley, thus melting the plastic w/p drive pulley. The whole thing needs to be disassembled, parts replaced, and test the w/p pulley for slop or grainy feeling when spun. You may have to cut the plastic drive pulley off the cam end (careful....) with a Dremel tool if it's been that hot............
sub - I think the plastic pulley has a metal hub, if I remember correctly
08-27-08, 03:46 PM
:yeah:.............Mine has a metal hub and is held by a round head Torx bolt.
Just doing the CYA routine and setting the OP up for a bit more than a standard belt change.....:sneaky:
What does the Torx head bolt do? Mine is pressed onto the camshaft stub
08-27-08, 06:19 PM
Good ol' GM.....tateos, take a look at the end of the w/p pulley/camshaft. Is there a threaded hole ? My '02 pulley has a metal hub with a puller groove machined in, and the whole hub is trimmed with a black round head #40 Torx bolt. Probably just a trim piece. Click in and look at the pic closely.........
08-27-08, 07:20 PM
Sub is right. There is a threaded hole in the end of the cam, that hole is there so you can thread in a jack screw to pull the pulley off. The machined groove is the same on most standard power steering pump pulleys. I used a power steering pump pulley puller to get mine off.
The internal thread on the shaft is also used to press the pulley back on the shaft. That torx head cap screw is probably there just to keep the threads clean would be my guess.
08-27-08, 08:56 PM
:thumbsup: I pulled the Torx bolt. The underside of the head is concave and it and the threads are full of grease. (and the "bolt" is plastic.)
Very cool discovery, sub. My '97 pulley had no such cap, and the threads were clean - I live in the desert - Phoenix - so nothing ever gets very rusty here.
08-28-08, 02:28 PM
It was the tension pulley that seized up, overheated the belt and that is what caused the cam shaft pulley for the water pump to melt apart.
It's funny I did not hear anything out of the ordinary.
I hope everyone adds this problem to their list of things to look at on their northstar.
I too am very surprised that the belt was not screaming for help.
what size bolt would you use to pull the pulley banck on the cam shaft
12-25-08, 02:00 PM
Check your other post on the same subject.......
12-26-08, 09:41 AM
M8 x 1.25 bolt. Metric. Any one of the exhaust manifold-to-cylinder head bolts will thread right in.
01-27-09, 06:06 PM
Just had the same thing happen to my 00 Deville today with no warning, water pump spins freely as does tension idler, but i suspect the idler might had possibly locked or something, my water pump was just changed about 5 months ago. The pulley melted into a ball. oops.....