How Fast Does Your Boat Motor?

[TooCoys]

I asked this on SailboatOwners, but thought I'd post here as well.

I've got a 1980 27' with a Yanmar 1gm10 in it, and it motors extremely slow.

We took it out yesterday for its first test sail since I bought it, and we were being passed by other sail boats left and right. It took us a good 30 minutes to go maybe 1nm?!?

I know that my cutless bearing is loose and will need to be replaced, which I plan on doing next month, but what else could be causing this?

Could the prop be slipping? At one point we though we were dragging bottom because we could hear and feel some vibration, but we were in at least 10 feet of water and I only draft 4.3'. We determined that the prop was turning because of the current as we down wave since the wind was behind us. Is that normal?

People keep telling me that sailing is just slow and that I am just not used to it, but when other boats my size are passing me, I'm starting to get concerned.

How fast does your boat go under motor?