Chain not rotating with crank

[Number4]

My 4.0 is out. Putting it all back together. Oil pan and timing cover are in place.
Installed a Melling M328 pump and was going to try and prime the pump manually by rotating the crank.

Start rotating the crank (without balancer on it) and the rockers are moving and pistons are 'try' to compress (plugs are out.)

Spun it quite a few times with a ratchet and was able to do it with some speed.
So I get out the 1/2" drill to give it a little more power. Only problem now, is the rockers stopped moving with the rotation.
When I look through the timing cover, where the balancer shaft goes, I can see that the crank gear isn't moving at all.
There wasn't any resistance during any of this.

So what did a "break" and what do I need to do now?

Getting ready to pop the timing cover off. Let me know if I don't need to.

 

[Number4]

Well, son of a biscuit eater.

Don't rotate the crank without the H Balancer on. The balancer keeps the crank gear fully seated.

What happened, is the crank gear slid out and the tooth or tab on its backside came out of the key way on the crank.
So now, I suppose I have to align the dots on the gears and find TDC. A little more research now.

I also may have used too much RTV when putting the cover on, I didn't think I'd get it off.

 

[vq5speed]

I never took mine apart but never thought the balancer would hold the crank sprocket on. Seems there should of been a keyway to lock it in. I know on Chevy's you need a puller to get that sprocket off.

 

[Number4]

The balancer keeps the crank sprocket full seated, keeping the sprocket from backing off. With it fully seated, the sprocket tab stays in the cranks keyway.

Now, if I rotate the crank until the intake valve opens and closes, then bring the piston to the top, with both valves now closed, this should be TDC.
The cam gear dot is at 6 o'clock and the crank gear dot is at 12 o'clock. I should be timed.

 

[vq5speed]

OK well I can see the sprocket walking out from being inline with the cam sprocket. But I don't see how the chain came off. How does the chain jump over the teeth. The chain is pretty wide even if the sprocket walked out some the chain would stay on. Now how far did you rotate the crank before you notice the rockers not moving. I don't think you could of gone complete revolution cause the piston would of hit a valve preventing you from rotating he crank. Just lining the timing marks up on the sprockets can still be 180 off. If you didn't rotate the crank that far before you noticed the rockers not moving you might be able to just back it up and line the marks up. You have to set TDC on the compression stroke not the exhaust stroke.

 

[Number4]

Chain didn't come off either sprocket. With the crank sprocket tab not in the key way, the cam sprocket, chain and crank sprocket just stayed in place while I rotated the crank.
The 4.0 OHV isn't an interference engine, so no risk of damage. Now it's just a matter of aligning the crank rotation with the that of the cam.

 

[natenkiki2004]

I don't think you'll have any problems just throwing it back together. The gears only go on one way in one spot. If you had both gears aligned when you put the chain on, and the chain hasn't jumped a tooth, just seat the crank gear back on the crankshaft and it should be fine. There's only 1 tab and 1 hole so putting it back at that spot, it shouldn't be out of time.