Friday, June 3, 2011

AutoProp Install (Finally)

Back when I first had Legacy hauled for the survey, I was struck by how much that big three-blade prop would affect sailing performance. It was then that I decided on some type of feathering prop. I agonized over the decision and wrote two blog posts, Decisions, decisions verse 1- Propeller, and Autoprop it is back in August of last year. Well, I did get the Autoprop but received it too late to have it installed while the boat was out of the water. I finally got around to getting it done this weekend.

My Mom and I took the boat over to Gig Harbor Marina to be hauled and have them install the prop. Gig Harbor Marina has the only Travelift and haul-out facility in Gig Harbor. It is a lot more convenient than taking the boat into Tacoma to have it hauled and my experience with them there at Gig Harbor Marina was excellent. The staff is friendly and helpful and seem very knowledgeable. Installing the Autoprop isn't a hard job, but I decided that since I don't have a prop puller, I'd let them do it. While the boat was out of the water, I had them wash down the hull and replace all the zincs. I have a diver that takes care of that for me, but since it was out it was easy.


The install went well. We did need to grind away some of the prop strut to give adequate clearance for the prop. Fortunately, a Catalina 400 owner who also has an Autoprop on the Catalina400 Yahoo group had mentioned the potential problem with clearing the strut. If he hadn't mentioned it, I'm not sure if either me or the installer would have noticed it. If you look at the photos you can see that the prop could have hit strut as it was changing from forward to reverse. A few minutes with a grinder and that problem was taken care of.


Here is a close up of where the prop would hit the strut.



After a couple minutes with a grinder, this is what it looked like.


Another, closer shot.


After waiting four hours for the tide to come in to give us enough water under the Travelift (it was a -2 tide today) we dropped Legacy back in the water.


With the standard 3-blade prop, 2500rpm would give us 6.1 knots on flat water with no wind. After the Autoprop was installed, we went out sailing on a beautiful day. Temperatures were in the 70's, we had 15 knots of wind, and it was bright and clear. (Those of you not from the PNW have no idea how unusual this is. We almost never get the combination of wind, sun, and warm temperatures. We are lucky if we get two out of the three.) Anyway with a 15 knot headwind and a light chop, 2500rpm now gave us 6.9 knots. More importantly, 2000-2200 rpm, which is a very comfortable power level for the Yanmar, gave a respectable 6.4 knots.

Reverse performance was better but it didn't eliminate the prop walk in reverse. This still means that getting in and out of our slip is going to continue to be a challenge depending on wind and tide.

Anyway, after just a short time I'm happy with it. Time will tell of course. Given the typical light winds we have here, I'm looking forward to seeing how it improves motor sailing performance.