sgtfury40

I just purchased a waterpump from ECS tuning. Have never had a problem with them in purchasing 996 or bmw parts until now. I ordered a water pump for the 996, it's a porsche part. Unistall the old pump (bitch) install the new and it won't turn. Pull the new pump off and the impeller is just over 1/16 of an inch wider than the old pump. I am so glad I found this out before I put it all together and just started the car. Otherwise, it would have broken those impellers for sure. Anyone of you had this happen? Guess I will have to wait until Monday now and go to the dealer and get one. What a pain.

Shark Attack

it is a plastic impeller? What I am about to say it TOTAL speculation from my own experiance.
I replaced mine a year or two ago and I also had an issue.

1, I pulled the pump down past torque spec.
2, this crushed the gasket too far
3, New gasket
4, redo job and pull to proper spec
5, Unit still rubbed on surface of block
6, pulled unit off AGAIN.. PISSED THIS TIME
7, noticed the block had like a sand paper finish where contact was made wtih the impeller.
8, new gasket reinstall, still rubbed SLIGHTLY
9, ASSUMED this was the way it was to be and the course block would sand down the impeller and seat it to make an unreal seat
10, ran pump with electric drill till it turned pretty free
11, started car and ran it... never looked back. 30K miles ago

dennis hiip

I had the same thing happen to me with a new 997 WP that is supposed to be a replacement for the 996 WP. I also caught it before starting the car. I got mine from a dealer and they apologized. Seems like there must have been a number of those WPs because most folks don't have that issue with the 997 WPs.

sgtfury40

IT is plastic impeller. Given the amount of difference in width of the impeller I don't want to risk the block sanding the impeller. There is a good chance it could break the impeller, then I could have pieces in the block. I would be surprised if Porsche designed the water pump this way. I'll let you know what Porsche says tomorrow.

ChristopherG

Possibly some sort of running change with the block castings?

dennis hiip

Mine was replaced with the "old" 996 WP by the dealer I purchased it from. The 997 impeller that I got was >1/16'' bigger than the 996 WP impeller. The 997 WP would not turn inside of the housing.

FastStreet

I would say your car had some other issue like the OP has because I know of several top porsche mechanics that routinely install the 997 water pump in the 996 now and consider it standard procedure as well as an upgraded part.

dennis hiip

The dealer (Sunset) admitted that the WP was at fault. Apparently there was a bad batch of them.

sgtfury40

The final chapter: Went to Scottsdale Porsche this morning and bought a new waterpump and could tell right away that it was the correct impeller size. Going to send the one I bought from ECS back. Porsche Scottsdale one was more expensive but I can't wait. Everything went in fine. Test drive, water pouring out the back end. I ended up somehow braking a plastic part that connects two upper coolant hoses. What a mess. Fixed that. Cleaned up the engine. Now working as it should. Beer. MNF.