How do I check cam timing??

[rodbuilder]

I have an early 6x4 that's not running and want to check the cam to see if it has jumped time. Is the cam gear driven, or chain driven and how do I check the timing on it??

HELP!!!!!

[xcopterdoc]

Gas or disel? Cams on both are gear driven. If its gas, To check timing, pull spark plugs and valve covers. Rotate engine until piston is at top dead center. Both valves on that cylinder should be closed, if not, rotate one more time to top dead center and check again. If the valves never close when at TDC, you have a problem.
If its a diesel, I doubt you'll ever see it jump time unless strange internal parts are hanging out the side. Just doesnt happen very often unless the engine completely comes apart.

[rodbuilder]

Thanks man. As far as ignition timing my buddy says it has 2 crank sensors so there's no way it could be out of time there - right?