Are  you talking about side play on the crank. I think its not to be no more then 5 to .008. To check it you have to check bearing pockets for wear. If their good your bearings wont move and they should hold the crank in place. I had to have my pockets fixed, they were letting the crank move side to side around .024. or how much room was in their for the crank to go side to side.  You can also put the primary gear on and the flywheel and pull on the crank side to side to see how much side play in it.