SoCal Jet Boats

Tech Talk => Jet Pumps => Topic started by: pure ndn on February 22, 2011, 09:14:34 AM

Title: when do i need a rebuild
Post by: pure ndn on February 22, 2011, 09:14:34 AM

i have a berkley 12 jc  b  i beach the boat 60% of the time the water were in  in the cove is only like 5 or6 feet deep in most spots
 i have scuffed of a lot of my hole shot power and about 10 mile an hour on the top end seems to just spool the motor up harder on take off but dosent jump out like it use to is it time and what all should i replace every thing or what and what impeller should i go with im 290 pounds and like my early morning skiing but like to go fast sometimes when the challange arises thanks for the info ;D

Title: Re: when do i need a rebuild
Post by: lbhsbz on February 22, 2011, 11:24:20 AM

If you're getting that "slipping clutch" feeling out of the hole and you didn't before, it's time to go through it. 

Check out the berkeley and american turbine website...one of them has rebuilding instructions with photos so you can familiarize yourself with it before you dive in. 

Most problems are due to the leading edges of the impeller getting beat up and/or the wear ring/impeller pilot getting worn and opening up the wear ring clearance. 

The basic rebuild is pretty simple, but after tearing into my first one a couple years ago, I found of lot of issues with what seems to be accepted as a quality rebuild, and chose to do things a little differently. 

For a stockish application, simply changing the parts and shimming the new or reconditioned impeller for proper wear ring shoulder clearance will be fine.  For performance applications if you want it to be as good as it can get, some machine work/alignment/balancing is in order.

Title: Re: when do i need a rebuild
Post by: pure ndn on February 23, 2011, 07:49:13 AM

thanks for the info  :thumbup:

Title: Re: when do i need a rebuild
Post by: TIMINATOR on March 09, 2011, 07:34:39 AM

True story. That. Pumps will, at full throttle, boat not moving, suck stuff off of the bottom from 4 to 5 feet! If you are in reverse, the reverse water blows stuff up right under the intake! I make a practice of never hammering the throttle from a dead stop unless the water is about 10 feet deep, but then again, I don't like throwing money away! We had a customer that always beach launched his ride, and would warm it up on the trailer by revving his engine, he killed his new pump in 2 months! TIMINATOR

Title: Re: when do i need a rebuild
Post by: pure ndn on March 09, 2011, 07:38:38 AM

thanks for all the sweet info i am very greatfull  ;D