What is your favorite jetboat break in method?

[treetopflyer737]

I have a 1997 Seadoo Challenger 1800 and just rebuilt the dual 787 motors top to bottom. I absolutely hate starting her out of the water with a hose because there is a lot of noise that typically comes from the drivetrain even though everything is in GOOD condition and I have read some owners claiming the jet pumps wear prematurely when starting these seadoo jetboats out of the water.

So with that being said and the fact I don't have a nearby body of water or pond in my backyard to use for initial break in... What is your favorite process for starting a brand new motor in one of these jet boats?

I was thinking something like this... (This procedure had worked well for two stroke motocross race bikes)


1.) Fire up one motor at a time and let idle for 2 minutes. Shut down and let cool. Listen closely to motor during this start up (even though the noise of the drivetrain will overpower the motor) and repeat with other motor.

2.) After motors have cooled from initial warm up run, restart motor one by one and give them a nice 1/8 throttle two-stroke clear out (blipping the throttle every 5-10 seconds) steadily increasing to 1/4 throttle clear outs, 1/2 throttle, and a few full throttle clear outs in order to clear out the newly rebuilt motors (that have a lot of two stroke premix coating everything for initial start-up). (3-4 minutes)

3.) Fire up one more time and after letting idle to warm clearing them out a few times with some 1/2-full throttle blips of the throttle. (3-4 minutes)

4.) Let cool and find a lake for first water test!

 

[racerxxx]

Well, I just throw the hose on it check for leaks. Head to the river, dunk it on the trailer. Start it, let it run a few minutes on the trailer, check for leaks. Take it off the trailer, idle out, get it up on plane and start to drive around. You can't really drop the rpm to low, once it comes off plane you're really putting a load on those new engines. So, I just vary the throttle on plane, yes the rpm range might be a little higher than breaking in a ski but you just have to. As far as running the boat on the hose??? I've been messing with Seadoos for over 20 some years, I ride in fresh water and salt water so I flush my stuff after every ride. I have never seen one iota of wear related to running out of water. You can also run the engines without the drive line installed, just make sure you have the pto torqued on correctly.

 

[Dr Honda]

You can't break in engines "on the hose". So it makes that question easy. You need a load on the engine... and you need enough water volume/pressure to properly look for leaks. (you don't have enough volume on a garden hose) Not to mention, your carbon seals are cooled, and lubed via the lake water. So... running it on the hose for any length of time... you are damaging your seals.

So... take it to the lake, and go run it.

 

[treetopflyer737]

Racer XXX great advice with the PTO tightened to proper torque if your going to run it without the drives installed.

Looks like I'll start the motors out of the water to make sure all is Ok and drive to a ramp where I wont be bothered and break her in there.

Thanks for the help you two.