Picked this guy up while hunting CL for jet skis. Kawi 550 motor/electronics, Berkeley 5JA pump, TB Woods coupler system, and alot of "custom" wiring that needs fixed.
I've been big into stand up skis for a while, I decided to give this boat a shot. Eventually, I'm putting in a 650+ motor, but sticking with the 550 until I get her buttoned up.
I trashed the motor coupler getting it off the crank (ruined the crank also), fortunately I was able to find parts to replace it. Some pics!

I have a few questions if anyone can help out....
What is the best way to get the most flow from the 5JA pump?  Another pump isn't an option right now.
Is there any A/M impeller options for this pump?
What is the thread on the input shaft to the pump? Metric, NPT, SAE? 18x1.5, etc.....
Anyone blue print these pumps?

Hell ya another mini boater!!

As you may know the Jet Lark is actually a very rare boat. They made a lot of Aqua Larks but the jet version were made in very few quantity because AquaLark was actually "the competition" so they had a hard time acquiring the pumps and engines. Awesome boat and great find. Can't wait to see what you do with it. BTW, you said you're a stand up guy...are you on any PWC sites?