Wednesday, September 25, 2019

Sep 2019: More Boat Business

The "Brain Box", a ZF/Mathers MicroCommander 585;
Servos & Physical Cable Connections Are Behind
the Printed Circuit Board.
In the days following the electronic throttle (and gear) failure we began pursuing answers…but we weren’t finding anything definitive.  Immediately after the event Rick had tested the electronic throttle station in the pilot house and found it nonresponsive – dead, unable to take control at that location.  But by the following day (Tuesday, 17-September) ALL THREE throttle stations were operating normally once again.  He ran the engines for a few hours to heat up the engine room – wondering if the “brain box” for the electronic throttles, which is located in the engine room, might be succumbing to heat related issues.  But after retesting the throttles following the heat soak, all stations again worked normally.

The next day, Wednesday, 18-September, Rick called on Ross Lund of Classic Yacht Service to visit the boat and assess the electronic throttle system, but absent any active misbehavior that would not be an easy task.  No electrical issues were found….voltage checked out at 13.3 volts at the control box, there was no corrosion there, and all but one of the wire terminals were tight.  The bare ground wire for “station 1” looked a little ragged, so Rick removed & trimmed it, then re-attached it more securely.  Ross and his helper Jerry found one potential issue with the physical cable running from the control box servo actuator to the transmission – the cable length was about a quarter inch too long, which theoretically at least might cause the servo control to keep trying to push it further and issuing a fault when it couldn’t.  They adjusted the cable appropriately.

The more common failure in these types of electronic throttle controls is loose or corroded connections at the throttle station(s).  Given we experienced failures at both the fly bridge and pilot house stations, Rick didn’t think that was the likely cause – a fault at one station is isolated from the other stations.  But to be cautious he spent some time examining the seven wire leads on the bottom side of each throttle.  The pilot house and cockpit units checked out tight and corrosion-free; the fly bridge station looked a little weathered and will require further evaluation and possibly replacement.
The Wiring on the Underside of the Throttle
Rather than just hope this 17 year old system wouldn’t fail again we had Ross order a whole new brain box.  The estimated price tag hurt (about three BOAT units once a new cable and labor were also factored in) but we were not going to be taking chances with such a mission critical system.  Having your 80,000 pound boat ping-ponging around the marina isn’t our idea of fun.  There was a gremlin hiding somewhere in that throttle system and we were determined to exorcise it.

While waiting on those parts the next step was to coordinate repairs to the physical hull and rub rail damage Ghost Rider incurred when it crunched the concrete piling following the throttle failure.  One of the go-to folks in this area with good references for fiberglass and trim repairs is Mike Peters with Brightworks.  Mike inspected the damage and thought the first pass should be wet sanding and buffing, so now we’re just waiting on an opening in his busy schedule to see how that turns out.  We were also concerned that the boat’s bulbous bow might have made contact with the docks; but on Friday, 20-September, our diver took an underwater spin around the boat and found only a minor abrasion in the bottom paint there.  That can wait for the next bottom paint job.

The Water Accumulator Tank with a
New Whale Fitting
In the midst all of this unplanned maintenance activity we encountered yet another repair opportunity.  During his routine below-deck checks Rick discovered some standing water in the mid bilge area.  The slope of that area isn’t ideal and thus does not fully drain to the aft bilge where the pumps are located.  Regardless, water doesn’t belong there, and the “taste test” revealed it was fresh water.  Tracing such leaks back to the origin is usually a frustrating treasure hunt – the source is rarely at or even near where the stuff ends up.  But after using a shop vac to suck the mid bilge dry Rick was able to trace a slow tell-tale water flow back to the water accumulator tank on the port side of the engine room.  The Whale compression fitting at the bottom of that tank had a steady dribble – which of course turned into a wild fountain fest when Rick fiddled with it.

After scrambling to close off the water manifold valves and cutting the circuit breaker to the water pump Rick got the wild spray under control – and then toweled himself and the engine room dry.  It was then simple enough to drain the accumulator tank into a bucket and replace the 15 mm Whale fitting with one of the spares we kept on board.  Re-pressurizing the system revealed a good fix.  To be on the safe side Rick also checked the starboard side of the engine room where the fresh water manifold resides and found the water-maker feed line leaking over there; re-tightening its connecting nut resolved that.
The Arrow Points to the Cheap-Looking Water Maker Line Nut

Coincidentally we were also in the middle of cleaning and draining the FRP water storage tanks.  This is the first time we’ve had to do that, as up to this year we had been on board and turning over the water supply often enough that it couldn’t go stale.  But after several months of non-use a mild odor made it obvious that water quality had declined.  A shock treatment of chlorine, followed by draining, followed by three gallons of Camco’s Cleaner-Deodorizer and two more fill & drain cycles got the job done.  That routine took most of a week, finishing up on Monday, 23-September.  We would leave three of the four tanks mostly empty (with a little of Camco’s Freshener product added) until we began more active use of the boat in a couple of months.
The Tropics Were Still Very Active But Not in Our Immediate Vicinity

In the meantime our weather had turned and stayed stunningly good.  While the tropics were still chock full of named systems, none seemed to be threatening our area, and the same upper level air flow that was keeping them away from us had brought us dryer than normal air.  It was a tad breezy and still warm, but we were enjoying abundant sunshine and reasonable (for us) humidity levels. 

It would have been fabulous boating weather.  Alas, that will need to wait until parts are procured, and repairs have been made and sea-trialed.  Hopefully we'll have more on that in the next blog post.

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