And Then There Was the Bow Thruster and Monsters from the Deep

Bob's View:

HINGHAM SHIPYARD MARINA

  Course:      Constitution Marina through Boston Harbor to Spectacle Island, then Hingham Shipyard Marina
  Seas:          None to speak of except being waked by the crazed Boston boaters
  Weather:    Sun and clouds, wind SSW- 10 knts, slight chop in outer harbor, wind came up to 20    knts SSW with 30 knt gusts in afternoon
  Distance run: 14 (N)


The issues with our vessel VELOMER continue to provide daily puzzles.  Today it was the bow thruster.  As we left Constitution Marina at 1130, we were unsure where our night stop was to be.  A call to Hingham Shipyard Marina, where we had stayed last fall on our way north back to our homeport of Spring Point, was made as we departed Boston.  They were not able to provide dockage for us as they had several boats extend their stay.  This was ironic as the reason we had to leave Constitution Marina was that boats were coming in that needed our space.  So it goes.  Anyway, we decided to make for Spectacle Island, part of the National Park System that encompasses several Boston Harbor Islands.  We found a mooring ball that was in 5 feet of water and picked this up against strong tidal current requiring me to use the bow thruster to force VELOMER's bow to starboard so PM could grab the mooring.  The pennant on the ball was extremely short so she rigged a line from VELOMER through the hoop on the pennant and we were secure for the time being.  The beach was full of  tourists escaping the urban heat and scene with screams from kids  jumping into the ocean's chilly water and parents seeking their wayward offspring adding a cacophony of background sound to the ferry horns and loudspeaker announcing arrivals and departures. 

We had a quiet lunch while we waited until 1400 when we expected a return call from Hingham.  As we floated off the beach, we had a conversation about the issues we had met with thus far and overcome.  I reminded PM that boats are like that, they provide constant entertainment with small and sometimes more critical problems.  The joys of living on a boat and cruising as we intend to do for the next 2 years will include numerous repairs, some clever adaptations and a great amount of patience.  A reality of a boat life is that boats float in a hash environment, including wind, waves, salt water and numerous other hazards with which to contend.  So things break or bend from time to time. 

The call back to Hingham gave us a berth for the evening.  As we dropped the mooring, I touched the bow thruster to starboard again to relieve the strain on the line so PM could release us.  There was no thrust, although the electric motor ran at high speed.  I remembered reading in the owners manual that this indicated a problem with the electromotor and shut down the system as advised.  The wind and current from a rising tide carried us into Hingham and the approach to Hingham Shipyard Marina.  Lacking a bow thruster, I maneuvered VELOMER with gentle thrusts from the single prop and adjustments to the rudder.  PM gave the dockhand, Peter, a mid cleat spring line, which I used to leverage the stern toward the dock.  This is first time I had utilized this maneuver and was pleased with the result. 

Bob in the V-berth checking the shear pin

So we had another system to fix.  There could be numerous causes to this failure.  The first and most easily diagnosed was a broken shear pin that connects the drive motor to the lower unit. Climbing into the V berth access, I uncoupled the motor. The shear pin was intact. Probable cause number 2 was a broken drive pin on the propeller shaft.  I considered free diving to check this.  If the pin was broken I would able to turn the prop easily.  The current from the falling tide coupled with the flow of the Hingham River runs to 6-7 knts at the dock,  so diving on the boat was not a reasonable or safe choice.  A short haul would be needed to confirm and fix the expectation of a broken drive pin on the shaft.  The shipyard could do this but not until Friday at noon.  Another night was arranged at the dock.  That evening I thought again about diving on the hull at slack tide the next morning but PM, applying her infinite wisdom, convinced me that as we had already paid for the haul at $7/foot ($252) we should wait for the next day to find out what we needed to do.  I contacted Jim Peterson, at Spring Point as they had just installed the new thruster.  He told be that if the pins are not broken, a problem that occurs 90% of the time and which by the way is not covered by warranty, it sometimes happens that seaweed wraps around the wheel and unwinds the prop from the shaft.  Hmmmm?  This was not passing the straight face test, but we would know more the next day.  The most likely problem was a broken drive pin.  This would be easily fixed. I had discovered spare drive and shear pins attached to the motor when I had worked in the V-berth the day before. 

First Haul at HSM

Friday, VELOMER was lifted from the sea as I sat on the curbside reading the diagram of the steps to replace the drive pin, PM announced "there is nothing there".  At first I assumed she meant there was no seaweed or stick preventing the prop from turning and causing a broken pin.  What she was saying that there was nothing there, no prop, no zinc, although the drive pin was still attached in the shaft.  Hmmmm?  seaweed, really?  A brief consult with Paul, the yard manager, determined that the best option was to order the parts and return VELOMER to the water in the meantime.  We launched and again maneuvered smoothly using the spring line

Nothing There

technique.  I was really liking this option to land against a pier with limited maneuvering room between two boats.  A call to South Portland, several calls to Imtra, the Sidepower wholesaler, and another to Defender and the parts were ordered for a Saturday delivery from Imtra out of New Bedford, Mass.  Friday night was arranged at the dock.  Fridays are the time of loud music at the local party stop at the head of the pier.  That was OK, we had a working AC and were only slightly aware of the very load music origination at the end of our dock.                          

Second Haul

The overnight delivery arrived the next morning, Velomer was hauled again, this time for $5/foot ($180), the prop, washer, locknut and zinc ($176 with shipping) replaced and we were back in the water, all in 30 minutes.  There being no reason to delay, we cancelled our next night dockage and headed out to sea with a repaired bow thruster sounding like it should and working like it was meant to.  Hmmm, seaweed?  I had found the lock nut really hard to tighten with the driver and the set screw securing the zinc, treated, as suggested in the manual, with locktight, also was a very tight fit.  I was seriously doubting the seaweed theory.  Perhaps Jim was also doubting it as he never called me back after speaking with Marty, the mechanic who installed the new thruster. The only explanation that makes sense to me is that the lock nut and allen screw securing the prop and zinc had not been properly tightened after installation of the new unit.

So I will contact Jim Peterson on Monday and "discuss the seaweed theory".