Rotax Type 717 / Sea Doo crankshaft

[David Hill]

I am trying to remove the " fly wheel " from the crankshaft and need some advice. I have made a puller attachment that I am quite proud of, but am unable to get the flywheel to come off. I am able to put quite a substantial pre-load on the puller, and am using a quite adequate hammer to impact it. I do not have an exploded view / picture and feel there is something I don't know. ( ie. is this thing threaded on or what ! ) Any suggestions on disassembly ?
Also, after disassembly I will probably be needing new pistons, bearings etc. Any suggestions on parts suppliers ? Maintenance /rebuild manuals and specifications ?
ThanX, .................Smokin' Dave

[dsolie]

Re: Rotax Type 717 / Sea Doo crankshaft

Dave, you are missing the important ingredient... HEAT! Use a torch and heat the snot out of the center hub. With the puller still attached, and the heat applied, TAP the hammer along the flywheel in a circle.. She'll come off...

[skisol]

Re: Rotax Type 717 / Sea Doo crankshaft

If the home made puller is really pulling and doing the job!!!!!

[gr8jpn]

Re: Rotax Type 717 / Sea Doo crankshaft

yep I agree, heat is the key.. my original 787 fought hard and just did not want to give up that flywheel.. about 10 minutes of heat from a propane torch and a few solid knocks with a small sledge and it sort of shot off of the crankshaft. I am sure I cooked the seals, but he has already indicated needing to rebuild.

I never could get the pto off.. I sent mine in with my engine and bought another one from SBT.

[David Hill]

Re: Rotax Type 717 / Sea Doo crankshaft

Thanks for the suggestions about heating the flywheel. I have been a little reluctant to heat the area due to the electricals behind it. Any suggestions about protecting the generator / alternator ?
Also I will be needing crankshaft work . Anybody have any suggestions ? I am in the Houston, Texas area................

[David Hill]

Re: Rotax Type 717 / Sea Doo crankshaft

Dave, you are missing the important ingredient... HEAT! Use a torch and heat the snot out of the center hub. With the puller still attached, and the heat applied, TAP the hammer along the flywheel in a circle.. She'll come off...

Thanks for the help. Any suggestions on protecting the coils and wiring behind the flywheel while heating ?

[David Hill]

Re: Rotax Type 717 / Sea Doo crankshaft

Dave, you are missing the important ingredient... HEAT! Use a torch and heat the snot out of the center hub. With the puller still attached, and the heat applied, TAP the hammer along the flywheel in a circle.. She'll come off...

Any suggestions about protecting the wiring and coils behind the flywheel?

[dsolie]

Re: Rotax Type 717 / Sea Doo crankshaft

it will be fine, just heat the CENTER of the flywheel, and don't go all crazy with a 4' flame thrower lol..

Heat it for a minute, then start tapping while still applying heat.

[David Hill]

Re: Rotax Type 717 / Sea Doo crankshaft

Thank you for your help ! Once I get the thing disassembled , should a shade tree aircraft mechanic proceed with disassembling the crankshaft or should I take it to a shop/ send it out ?

[dsolie]

Re: Rotax Type 717 / Sea Doo crankshaft

SHOP! Those cranks need to be pressed and indexed to bery precise tolerances. Usually, it's not worth it to rebuild. It's cheaper and quicker just to get a crank via exchange from SBT or a new one from Hotrods etc.