What an amazing cruise: with my 85 year old mom aboard we set out for Roche Harbor, arguably the Disneyland of all resorts in the San Juan Islands. All systems go. Sandavore has a sizeable Lewmar bowthuster installed, and I’m not ashamed to say that it quickly became my Go To for close quarters maneuvering. Single engine, full displacement fishing boats were not designed to delicately maneuver in reverse; on our first trip out 2+ years ago I quickly discovered that the rudder is entirely useless in reverse. Full port, full starboard….still goes straight back. She’ll pivot like no one’s business in forward gear! So a bowthruster is a godsend. I am hooked.
After Roche we remained overnight at Friday Harbor then headed home for our annual refuel (114 gal taken on), black water pump out, and back into the slip. Indeed, we back her into the slip every time to minimize environmental exposure (covered slip). Headsets on, girls astern and guiding me in, no wind, no current, sunny, yeesh! Perfect! Plenty of taps on the bowthruster, nearly all the way in and-
WHIZZZZZZZZ
It took me about 0.5 seconds to realize that the bowthuster had decoupled. I tried it again.
WHIZZZZZZZZ (and not the solid growl of the thruster props)
“OK, we lost the bowthruster. Please be aggressive with the fenders and I’ll go slowly.”
After we got settled in and tied up we all let out a collective THANK YOU SANDAVORE! Made it all the way home before this happened. And literally in the slip. It doesn’t get luckier.
Although I’m not certain (and neither is Mark the mechanic), it “sounds” like either the blades all departed or the lower unit, i.e., transmission, has failed. Both happen: it only takes a stick to shatter a blade; and though the sealed stainless unit is meant to last, would anything immersed in salt water for 12 years straight? The shock mount decoupler is intact, so it’s probably still splined to the drive unit. Mark suggested a diver but I’d already made a haul out appointment and it was about time for a pressure wash and inspection, so…..
Haul out scheduled for 19 AUG, unit is being shipped from Lewmar. To be continued!
19 AUG 2022 update
With Marco’s steady guidance at La Conner Maritime Sandavore was slowly hauled out on a dead calm morning. Standing at the bow I watched the tunnel emerge from the water to see e-v-e-r-y single blade missing from both props of the bow thruster.
Probably ingested….something. Once a blade goes the other ones aren’t far behind because they in turn whack the attached ones. Think turbine blade failure in a low speed jet engine. Recreational bow thruster blades are almost always carbon-reinforced plastic. It was explained to me that they are designed to be the first point-of-failure, for two great reasons: metal blades spinning at 500-700 RPM could depart and damage or penetrate the tunnel or hull, causing an instant compartment flooding issue; blades are $hundreds to replace and can be done by a diver, while lower units and motors are $thousands and require haul-out. This thruster has 2 counter rotating props. Mark checked the shafts to ensure that they weren’t bent, then it was a simple matter of remove and replace.
Final input: I gotta tell you that it’s disconcerting to watch a wooden boat fly. I’m less prone to silently scream when I see it, but I’ll probably never get used to it….