Roof Leak...

[MoDutchmen]

I have a 96 Jayco eagle 10. It seems to have a small leak. Apparently it hasnt been leaking long because there are no stains on the roof. I looked under the AC unit today and noticed the seal looked to be in great shape until I got to the back of the unit. There was no seal at all. Is this supose to be like this? Ive got some of the good tape to put on the seam down the middle of the roof. Doesnt look that great but it works awsome. So anyone know about the AC Seal?
Thanks
Dave

[PattieAM]

You might want to check your owners manual for your AC - mine has a list of parts with pictures and my 'seal' goes all the way around the unit.