DW7er head hard to 734 cutter head hard to raise

On my DW734 the cutter head will not raise without using a lot of pressure and then there is a loud bang and  the cutter head will raise a tiny bit. I have taken off the side panels and cannot see anything obvious that is causing this. What could be the problem?

 

Thanks,

 

Duane

I have the 733 planer.

What do you mean by a lot of pressure? Turning the crank handle require a lot of pressure? How familiar are you with this whole unit because it has the locking mechanism that keep it from creeping up or down, make sure that is loose first… Just trying to think of a few things to eliminate first off…..