Help!! Yamaha 2000, Trying To Get The Flywheel To Spin

[edimonster77]

Hello I have a 2000 70 hp 2-stroke Yamaha, that I am trying to free up the pistons. I removed all plugs and tried to spin the flywheel by hand and had no luck.

I was told to try mystery oil and let it soak in the cylinders for a few hours or days. I have not tried that yet. I am building a stand for it before I can try the mystery oil deal.

Does anyone know of any other remedies to get the piston to free up???

Any and all help will be appreciated!!!

 

[Manjonning]

Just bought an Ebbtide Dyna Trak fish/ski .. it came with a 87 Yamaha 115 LH .. worked fantastic for a week .. then the motor quit on the lake - ended up trolling back to the launch. I have a mechanic buddy who told me it was a battery/connection problem - he came out today and everything seem fine - he then tried to turn the flywheel and it was stuck. We pulled the plugs and lower unit.. nothing looked bad.. the cylinders were used but not bad ..We sprayed penetrating oil and fogger into all the cylinders - cranked the fly wheel around a few times with a break bar socket wrench.. then put it back together hooked up the muffs and I barely hit the ignition and it turned over... We are stumped as to why this happened and what caused it.. and what we did that helped it. I've read things about this happening who used a impact wrench to break it loose - but mine would crank almost all the way around then stick.. either way .. I'd love to hear from another owner or mechanic that had this happen ... and if it was the beginning of a rebuild or if it worked as a long term fix?

 

[GA_Boater]

Just bought an Ebbtide Dyna Trak fish/ski .. it came with a 87 Yamaha 115 LH .. worked fantastic for a week .. then the motor quit on the lake - ended up trolling back to the launch. I have a mechanic buddy who told me it was a battery/connection problem - he came out today and everything seem fine - he then tried to turn the flywheel and it was stuck. We pulled the plugs and lower unit.. nothing looked bad.. the cylinders were used but not bad ..We sprayed penetrating oil and fogger into all the cylinders - cranked the fly wheel around a few times with a break bar socket wrench.. then put it back together hooked up the muffs and I barely hit the ignition and it turned over... We are stumped as to why this happened and what caused it.. and what we did that helped it. I've read things about this happening who used a impact wrench to break it loose - but mine would crank almost all the way around then stick.. either way .. I'd love to hear from another owner or mechanic that had this happen ... and if it was the beginning of a rebuild or if it worked as a long term fix?

Please start a new thread. 8 year old threads are not the place to get the answers you need.

Closed.