Wednesday, April 17, 2013
"Pretend your bow thruster just went out ..."
Posted by Sean
In the latter half of our training, that phrase was repeated many times by Captain Gary, at a number of docks and in differing conditions. I am paraphrasing, of course -- Gary never said "pretend"; he simply announced at inopportune moments that the bow thruster was no longer working. Once he even surreptitiously turned it off at the breaker and I discovered it to be inoperative as I approached the dock. Good training, we thought, as our bow thruster had already quit once, early on, and Captain Buddy-the-shrimp-boat-skipper had to rescue me.
Yesterday, there was no pretending about it; the thruster quit for real as I was trying to spin the boat around in a narrow fairway of the Osprey Marina near Myrtle Beach, South Carolina. And there I was, with the boat caddywumpus in the middle of the marina, still yawing with no easy way to null the rate. A brisk wind was pushing us to the lee shore, and I had to think fast on my feet.
Fortunately, being mid-spin, I had no way on to speak of, and there was some maneuvering room ahead of me, although not in the direction of our assigned dock. The big barn door rudder will spin the boat around on a dime if I goose the throttle with full rudder, and I needed to get turned around before the wind trapped me in a little triangle between the cypress trees and the finger piers. The inevitable audience was probably wondering what kind of idiot guns the throttle in a quiet marina, emitting big clouds of greasy black smoke, but it worked to get us pointed in the right direction and we tied up at V-dock, as directed, with no further drama. For the literally alliterative, that means we have Vector at Victor-dock.
Once I had the boat pointed the right way in tight quarters, getting to the dock was a piece of cake, and we could have tied up on our own, but seeing the spin-around drama, the lone dock hand came racing over in a golf cart to help. The golf cart is necessary because V-dock, while only perhaps a hundred feet from the fuel dock over water, is more than a quarter mile around the basin from there and everything else.
We had not really intended to be in a marina last night, but given the thruster failure, we are glad we ended up here. Our plan had been to anchor just a mile or so south of here, on a little oxbow off the river. When we arrived there at 2pm, however, there were already three boats anchored, with two of them rafted together. The only other spot in the oxbow suitable for us had a mooring ball in it, perhaps someone's "reservation" of that prime spot while they went off to do other things. That was the last anchorage northbound until after the "rock pile," which meant either going back south to look for a better anchoring spot, or coming here for the night.
This is a great marina, with reasonable rates, a little store, and, seasonally, a counter-style restaurant. This latter item was closed yesterday, but nearby Scatori's Italian Restaurant, in addition to delivering to the marina, is happy to pick dine-in guests up, and even though we had planned on leftovers for dinner, after the thruster episode we were happy to get out. As a bonus, we were able to restock a few items from the Lowes grocery store next door to Scatori's. Louise reports that her frutti di mare was the freshest and best she has had in a long time, and my shrimp fra diavolo was excellent as well.
After tying up, and taking a few deep breaths, I went to work on the thruster problem. I thought we might have sucked a stick into the tunnel; we had heard at least one submerged object hit the hull on our way north through the Waccamaw, which is rife with logs and other debris. As soon as I got the access cover open I could smell burning electrics, and as I glanced at the batteries I could see char on the negative cable. As soon as I touched it the cable came off in my hand with a giant spark. A small pool of molten, then re-hardened lead sat atop the battery.
Long-time readers may recall a similar issue we had with Odyssey's house batteries. It does not take much to make this happen; in this case, I would guess that the wimpy wing-nut holding the battery cable to the post adapter loosened ever so slightly from vibration over time (although I had tightened them all during the last great thruster project), increasing the resistance of the connection. From there, ohmic heating under load can heat the terminal to the melting point of the lead, loosening things further and leading to more ohmic heating in a vicious circle.
We had used the thruster while retrieving the anchor yesterday morning, and again just a mile from here as I maneuvered out of the anchorage we could not use. Spinning the boat here at Osprey was the last straw, and even though I had only used the thruster a total of perhaps 20 seconds here, that was enough to make the connection part completely.
I hopped in the golf cart that the marina provides for its V-dock guests, and zipped over to the office/store. Amazingly, they had a package of battery post adapter terminals on the shelf, and less than four dollars later I was on my way back to Vector, parts in hand. I spent a half hour crammed in the thruster bilge cleaning char off terminals and getting the new adapter in place, but our thruster is once again working, and we did not even blow the expensive 250-amp fuse. Some days, you just get lucky.
In a few minutes we will head back out into the ICW to transit the rock pile on a favorable tide. I expect once again to be at a marina tonight, as there are really no anchorages for some distance further.