I am a newbie and have a new to us 1997 Coleman Fleetwood Sun Valley. I have a hand crank system that “pops” when it is raised. It does not do that going down. I have adjusted or righted all the cables. The back end of the whiffletree would bounce when it was being raised so I think I have fixed that. The chain appears loose - I can push it together between the two sprockets easily. But if I remove a link to tighten it, I can’t get the chain back together. Just the one link removal seems to make it too short. Do I need to replace the bearing on the whiffletree? I have been doing various repairs on this camper since purchased and still haven’t used it yet. Any suggestions would be appreciated. I am in central Texas.