I recently purchased a new to me boat and the roller furler has a single line. I thought they had to be spring loaded, but it appears not.
Very important! Another club member lost his head sail to the wind a few weeks ago. Very expensive mistake!Be sure to furl it so that the sheets wrap around the sail about 3 times, and cleat the furling line, to prevent it from unfurling itself in a storm.
I use a longish flat blade screwdriver to keep, the drum from moving when we have named storms come in. I also tie a few sail ties around the furled jib. If it’s going to blow much over 50kts everything comes down.You should also see if there is a place to insert a pin in the drum that would prevent unfurling.
I had to readjust my CDI a few times to get that right. My continuous Seafurl 810 doesn't matter.One thing you will want to check is that when the jib is furled tight that there are still a few turns of furling line left showing on the drum. If not, in a high wind she may furl tighter and you will have no line left with the sail still not 100% furled. An easy fix, if not, but an unimportant one.