1998 200HP servicing water pump but...

[<Steak>]

Dilema...
I bought my self a Clymer service book the other day at the marina, and decided to do the water pump impeller service, I took off all the nuts from the lower unit, disconected the speedometer tube, took off the trim hidden nut (top and bottom).. and the lower unit dosen't even move!, I try shaking it amd it is rock solid... any ideas on how can I take it down so I can perform the service on the impeller?

Thank you!

[<steak>]

well, finally got it off, PB Blaster and a 2x4 with a hammer did the Job, one more question, I took the old impeller off and I found a white round plastic tube inside the impeller that was imposible to fit inside the hole of the new one, but the newone fit perfectly without this white tube inside, so I left it like that... anyone seen something like it before??... again my engine is a Yamaha 200HP 1998.

[<boats.net>]

There is white plastic sleve that goes above impeller on some models. There would be flat washer and wave washers that go on top of impeller then the white plastic sleve then the metal cup fits over plastic sleve