The gear that drives the distributor doesn't turn. My neighbor advised that I pull timing gear cover and check for a broken key on the cam gear. When I try to unbolt the starter jaw (for the crank starter) the nut turns the crank in both directions. How do I get that jaw off? Is there a bigger problem?

Eric, Before you pull the cam take another look at the roll pin (or rivet) that secures the distributor gear to the shaft. It is not always obvious by visual inspection or turning it by hand if the pin is sheared. Drive it out to be sure. In my experience with engines I would think the cam drive gear would be machined as an integral part of the shaft as opposed to being keyed, but I haven't been this deep into the 124 and don't really know how it is constructed. If you have to pull the cam, another option in pulling the pulley is using a ball bearing puller. It is shaped like a split clamshell and applies the force near the shaft part of the pulley. Be careful and good luck. Joe

The distributor drive gear on the 124 cam is integral with the camshaft - not a likely point of failure. Neither the parts nor the service manual illustrate it, but the gear on the bottom of the distributor shaft is a replaceable part.

Remove the rocker cover, rotate the crankshaft and watch the rocker arms for movement. If the rocker arms are ALL doing what they're supposed to be doing, chances are that the pin in the distributor gear is sheared. If NONE of the rocker arms are doing their business you'll need to pull the timing cover and check the cam drive. If SOME, but NOT ALL, of the rocker arms are being actuated you're looking at a broken camshaft.

Any of that make sense?

Thanks guys. I'll probably start Thursday after work. I'm not sure how far I'll get. My job is sending me back out to St. Louis (I'm based out of Cleveland) for 2 weeks at a time.