I recommend getting a whole new crank. Mostly because the LT80 cranks are thin where the rod end is compared to a 250R crank, thus it is very hard to get them straight.
I watched a guy do a 250R crank in literally minutes. I then watched him mess with a LT's crank for a hour. Nuff said.
I use a fine sand paper and sand where the bearing sits on the crank till the bearing slips on tightly (both sides).
Also sand/clean the guide dowels so the cases can slip right together.
You will need to use heat to assemble. I use a woodstove. Charcoal works well also. I don't recommend a torh unless your skilled enough as to not "all of a sudden" melt a case half. Aluminum ya know.
Stick a bearing on the left/clutch side of the crank. Heat the left case half and slide the crank/bearing right in. Stand it straight up and let cool.
Coat center with yamabond,,honda bond,,etc. (that greay thick stuff)..
Do the same for the right side. Tap the right case half down using light taps. It should slide right together.
Tighten the bolts and your done. No real torque setting,,
Crank should spin freely.
When all is cool, the seals can be pushed in. Lube the seal where it contacts the crank.
Nothing is really pressed..it just seems that way comming apart.
I just hit the crank till it comes out. heat can be used .
Hope that helps.
2000 GNC 5N\
2001 GNC 9N \ 40+ class
2004 GNC 9N /
2014 rock crusher "GO tortoise GO!"
2016 Byrd Rooster
Father of the "11" time National champion,and worlds fastest woman ATV racer
A few fast LT80's
250R~300cc's
300ex
350 Rancher
Kymco Mongoose
Survivor of the 12 Hours of ATV America 04 and 05