Ordered my rebuild parts for my 2005 250cc sherco last night from splatshop and im trying to think ahead of which way im putting back together. Ive done engines in the past where i didnt need a crank pulling tool to get the crank back in. 

Has anyone got a tried and tested method to get the crank back in safley without damaging something? 

Mink_man 

Bearings/crank in the freezer, warm crankcase evenly with hot air gun. drop the bearings inti case make sure they are seated.  warm the bearings/casings with hot air gun again and fit the crank and then the other casing. may need a small tap on either side of the crank when the casings come together and then  recheck casing bolt torques. works for me everytime  

2 hours ago, mrturtle said:

Bearings/crank in the freezer, warm crankcase evenly with hot air gun. drop the bearings inti case make sure they are seated.  warm the bearings/casings with hot air gun again and fit the crank and then the other casing. may need a small tap on either side of the crank when the casings come together and then  recheck casing bolt torques. works for me everytime  

Thanks MrTurtle, a great help. What torque setting did you use?

m6 bolt torque into aluminium is usually around 7-10 Nm depending on application.  8Nm is what i used in a star pattern. 

If you heat up the crankcase enough you will find the main bearings drop into the case and fully seat with no other force.            when you have done this  heat the bearing in the case and get it hot enough so you can put the frozen crank in the same way without force. Just make sure you have the conrod in the correct place!   heat the other main bearing/ case just before you close up the halves and it should go together with no drama. Once you have them together with bolts in snug,  tap either side of the crank with deadblow or hyde mallet etc until it turns freely then torque the bolts and check the crank rotates nice and free.

 HTH

jason

 

3 hours ago, mrturtle said:

m6 bolt torque into aluminium is usually around 7-10 Nm depending on application.  8Nm is what i used in a star pattern. 

If you heat up the crankcase enough you will find the main bearings drop into the case and fully seat with no other force.            when you have done this  heat the bearing in the case and get it hot enough so you can put the frozen crank in the same way without force. Just make sure you have the conrod in the correct place!   heat the other main bearing/ case just before you close up the halves and it should go together with no drama. Once you have them together with bolts in snug,  tap either side of the crank with deadblow or hyde mallet etc until it turns freely then torque the bolts and check the crank rotates nice and free.

 HTH

jason

 

Thanks for this again Jason,i should recieve the parts in the next few days and hopefully ill have the crank back by then! fingers crossed this weekend ill have it together again!

On ‎11‎/‎14‎/‎2017 at 2:54 PM, mink_man said:

Thanks for this again Jason,i should recieve the parts in the next few days and hopefully ill have the crank back by then! fingers crossed this weekend ill have it together again!

I hope you ordered the VITON seals!

7 hours ago, copemech said:

I hope you ordered the VITON seals!

Yes,yes i did

Sitting by the door at work waiting for the postman (or woman).