SEA-DOO 720 PTO AND FLYWHEEL INSTALL

[DAVID_HX_XP_RX-DI]

Hello Bryan,
In the SBT instructions it tells you to stuff a clean shop rag through the exhaust port into the cylinder to cause interference with the piston. This will, in turn allow you to loosen the Flywheel and the PTO "wheel" on the opposite side of the crankshaft without turning the crankshaft.
I assume you do the same when replacing those two components as well.

My question is: Since the Flywheel requires 107 ft./lbs. torque and the PTO requires 81 ft./lbs. torque to tighten (rather serious torque levels) dosnt this put alot of stress on the piston edges and rings?
Is there any chance of damaging the crank alignment by TIGHTENING the Flywheel nut and PTO using this method during re-assembly ?
Is there a safer alternative ?

David

[Bryan Glynn]

You would only risk damage if you were to apply sudden force while tightening, like a hammer blow. Steady tightning torque is just fine - and the rings are not touched at all.

[DAVID_HX_XP_RX-DI]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Bryan Glynn - SBT Webmaster:
You would only risk damage if you were to apply sudden force while tightening, like a hammer blow. Steady tightning torque is just fine - and the rings are not touched at all.<HR></BLOCKQUOTE>

Good, I have a freshly calibrated "Snap-On" torque wrench.

Does the paperwork that comes with the engine designate what size (oversize) pistons that have been installed?

I am having my OEM 38mm Mikuni Carbs. bored to 40mm (at the venturi) and having a primer kit installed as well as installing a R&D Power Plenum F/A (In order to return the OEM Carb. brace).
Also, my HX already has a Factory Pipe W/ ECWI installed and the overall set-up for jetting/N&S size/pop-off and LOW/HIGH speed screw settings will depend upon the new engine cylinder displacement in addition to these previously mentioned factors.

Any accurate carb. set-up suggestions would be appreciated. (Taking into account what I just mentioned).
Lake level is 812 ft. above sea-level, relative ave. humidity 78~85%. Running a Scat-Trac Swirl 14.5/21.5

I am rather critical about these Carb. settings since my previous engines' FRONT cylinder was fried by a too lean condition/detonation problem, which, I believe has been corrected. I will also be installing a high output Mikuni fuel pump.
is their a Mikuni Carb. Guru at SBT that can offer a proper set-up ?

David "On the Tennessee River"

[Bryan Glynn]

Your pistons are 1.0mm (0.040") oversized.

We really don't do high-performance work, nor have the hands-on experience to give you accurate jetting recommendations. I would contact Bill O'Neil at www.watercraftmagic.com

[DAVID_HX_XP_RX-DI]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Bryan Glynn - SBT Webmaster:
Your pistons are 1.0mm (0.040") oversized.

We really don't do high-performance work, nor have the hands-on experience to give you accurate jetting recommendations. I would contact Bill O'Neil at www.watercraftmagic.com<HR></BLOCKQUOTE>

Bryan,

So you are saying that ALL SBT SEA-DOO 720 engines are either bored to 1.0mm (0.040") oversized or re-sleeved and are bored to 1.0mm (0.040") oversized ? That is very good consistancy, can I count on it !?

David

[Bryan Glynn]

Exactly.