RE: Foreman 500 Timing
The crank timing mark is on the flywheel "stator side". to check the timing mark on the camshaft you can remove the water pump and see it it's not that easy to see it but it can be done w/o removing the head.
Is it the cam chain thats loose, or the oil pump drive chain? you can manually adjust the cam chain tensioner to take up the slack. If it's the oil pump chain that's loose you have to replace it.