HJ60 2H, are they a interference motor - ie, get the timing wrong &...

All diesels have almost no piston to head clearance, ie, they are high compression 16:1 12HT and around 22:1 2h.

Get it wrong and it will destroy something or many things.

The timing gears are clearly marked and should be easily placed in the correct timing positions especially if you have a Factory manual. In mine, it shows a schematic diagram of all related rotation components.

If you have already rotated the engine multiple times it must be in synch otherwise it would be caressing other essential items. You can of course have the pump timing way out and not in synch as it only works in concert with the engine as well as synched for correct operation.

Any crashing usually results in bent valves and guides, broken rocker gear.

Always MANUALLY turn ANY 4 stroke engine 2 complete turns to ensure there is no collisions before ever cranking it. Failure to do that often results in wet handkerchiefs.

Landcoaster - The 2H is definitely an interference design engine. I cannot see how anyone could install a different-sized gear in the timing gear train, it would wreck all the timing.
It's more likely that one or more timing marks are out because someone used an aftermarket gear or gears that were not marked from the factory, and they then marked them incorrectly.

Cheers, Ron.

a huge thanks for everyones input...it has helped clear up the issue and we can move forward...