'13 EC300 Blown Transmission

[bkoz]

Hello to the forum. I have my friends 2013 EC300 in my garage right now with a slight transmission "issue".



The worst part is the RHS case is cracked at the shift drum bearing bore.





I have a few questions I was hoping the board could help me with:

- I am guessing that Gas Gas recommends replacing both case halves together?

- The owner has a paper copy of the '05 shop manual. It looks like there are very few changes engine wise from '05 to '13 minus electric start?

- The owner also has a '05 250. We are thinking of pulling the '05 bottom end and bolting on the '13 jug and flywheel/electric start. Will this fly?

- The '13 engines top end tested out to 135psi on the compression tester. I am guessing this is low. The top ring looks to have a pretty large gap just looking at it. What do you guys like to see as far as a good compression test?