I need some advice, i have a 21' kachina it had a stock 460 with a 12jc pump. It now has a 500hp 454 with the same pump but now it feels like a tranny slipping when u stand on it. I rebuilt the boat but have not touched the pump. Any advice, much appreciated.

Did you rebuild your boat yourself?

Do you want to fix your pump yourself?

If so you'll need a few special tools and there's plenty of advice here to step you through.

It's easy to measure the impeller to wear ring clearance and pull the bowl off to take a look.

Pulling impeller is a process with the special tools. Also depends on how long it's been on there.

Download the Berkeley manual, it's only a few pages and a good read before attempting anything.

I like to do everything myself too.

Let me know if you need anything, I've had easy rebuilds and 1 that sucked.

Couple of tricks I use:
1/2" air ratchet to remove impeller nut. Heat it a little first.
Always heat the impeller close to shaft with a torch before trying to break it loose with the puller.
I use a lot of anti seize when I put it back together.

Enjoy