Shaft Seal Replacement in Trinidad: Nov 4 -18, 2009

Click on the above thumbnail for a map during this time period

The following article was submitted to the Krogen Cruiser Newsletter.  I include it here because it contains in one package the complete story of an episode that has appeared in bits and pieces elsewhere in these blogs.

A Hard Nut to Crack

Nov. 18, 2009

While cruising during the summer of 2009, I noticed that the “dripless shaft seal” wasn’t.  That is, it was dripping.  I dug out the documentation for the “SureSeal” product available from Tide Marine – the product that Kadey-Krogen is installing as standard equipment on the Krogen 48.  Read that there should be additional seals on the shaft, and checked to see that two were indeed there.  Since we were intending on going on the hard in Trinidad during September/October, I decided to wait until our return from the States to accomplish the change of seal in a stress-free environment.  No leaks – no fuss – no water to come rushing in during the seal replacement.

There was a list of about 20 things to be done when we returned, and I saved the “easy” seal change until near last, in part because I had taken a bad spill  -- two spills, actually – on a trail bike and had sore ribs as a consequence.  The published replacement procedures were simple:  1.  remove the front of the seal housing, 2.  extract the seal from the housing,  3.  sever it so that it can be removed from the shaft,  4.  open the nearest standby reserve seal compartment,  5.  slide the new seal into place in the seal housing, 6. replace the front of the seal housing.  7.  consume a rum punch.  (Actually, the last item is a Tusen Takk  II – specific item that is attached to the end of all procedures that exceed more than three steps.)  On Nov. 4, as soon as I began the procedure the complications began:  I got stuck on step one; I couldn’t remove one of the bolts securing the front of the housing.  I finally realized that the plastic housing was cracked, and that the nut receiving the bolt was turning inside the cracked housing.   Nothing to do but remove the entire housing, and no way to do that other than to destroy the front of the housing with a good old-fashioned hacksaw.  But of course, removing the rest of the old housing would now require releasing the shaft from the transmission and removing the coupler.  And of course, I needed a new housing.  And that is where the first set of additional complications arose.  I made an immediate call to Tide Marine, in Deerfield Beach, FL, and placed an order for the appropriate seal kit.  (The kit also contained a new hose coupling  -- it seemed prudent to replace that as well.)  FedEx got the order to Trinidad quite expeditiously; it arrived on Monday, Nov. 9.  Unfortunately, it was not delivered to Peake Yacht Services in Chaguaramas, but was instead delivered to the holding warehouse associated with Customs at the very distant airport.  Unfortunately, I had forgotten to ask that the FedEx label feature prominently the name “M/V Tusen Takk II”, and just as importantly, the phrase “Vessel in Transit”.  So the item nominally required the payment of a hefty customs fee, and the item was being held at the distant facility to insure that the fee was indeed paid.  Multi-page paperwork was sent to Peake; on one page there was the notation “Vessel in Transit??. “  Peake gave me the paperwork, and on my request graciously called the airport Customs to assure them that the vessel was indeed “in transit” and therefore exempt for customs duty.  No joy.  I was to take the paperwork to Chaguaramas Customs (along with my incoming customs forms, etc.) and have them add notations to the paperwork.  Then, leave the paperwork back at the Peake office, where FedEx would pick up the paperwork, take it to the airport, secure the package, and bring it to Chaguaramas Customs.  The paperwork was picked up on Tuesday morning.  Wednesday, no package.  Calls to FedEx invariably led to the report that the package was at the airport warehouse.  Explanations of the circumstances were as water running off the back of a duck.  Thursday, no package.  More calls to FedEx.  More trite analogies to well-oiled ducks.  On Friday morning, we got a call from the Trini FedEx person in charge of packages destined to vessels in transit, with the message that the paperwork had finally been processed and that the package had been cleared to arrive at the Chaguaramas Customs on that morning.  Barb immediately dedicated her morning to being at the customs office when the package arrived, and pedaled off on her bike with a book and backpack.  The package arrived at 11:59 am.  Barb arrived back at the boat with an attitude of triumph and/or relief that was all-too-brief.\ 

For the complications continued.  Releasing the coupling to transmission had been easy.  Sliding the shaft back had been easy.  But.  Inside the coupler is a nut that cannot be engaged with a normal wrench.  The nut has four indentations that are at 12, 3, 6, and 9 o’clock.  Krogen 48 vessels are supposed to all have a “key” that fits into two opposing of those indents.  No such key is on our vessel.  So we had taken some careful measurements, and had taken a picture of the nut within the coupler, and had taken our problem to the local machine shop.  He found what he thought was a sufficiently sturdy thick pipe, and cut out fingers that would fit into the four indentations.  Holes drilled into other end of the pipe would provide a way to attach a bar.  We stuck a pipe over the end of the cheater bar to provide extra leverage, and based on the advice garnered from Krogen as to direction of threads, proceeded to give a mighty push.  Many pushes.  Nada.  Nichts.  Ingen ting.  No joy.  Except that the makeshift socket kept flying off the nut.  Worse, the fingers of the socket were bending.  Back to the machine shop, where reinforcing segments were welded onto the insides of the fingers.  More calls to Krogen, and more assurances that – at least in recent Krogens, the thread is the standard “lefty-loosey” variety.  A hopeful post to the Krogen Cruiser List received several sympathetic responses but nothing specific.

 And then, two crucial developments.  First, we decided to redouble our efforts to determine which way our threads ran on the end of the shaft.  We had had no luck with close-up photos and the use of calipers, but eventually, we hit upon the scheme of pressing picture-mounting clay into each of the indentations of the nut.  On the image on the clay, we measured the distance from the end of the shaft to the first ridge of the threads, and realized that on our vessel, the threads are not lefty-loosey.   We had occasionally, of course, in desperation, attempted the clockwise direction, but most of our efforts  -- and the most vigorous – had been in the conventional counter-clockwise direction.  Ouch.  

 The second crucial development, after finding that the strengthened socket – no longer bending and no longer slipping – was still not working even after we were applying force in the correct direction, was to start all over in the creation of a tool to remove the nut.  We chose to modify the design provided by Fred Blockland, head of service at Krogen.  Basically, all we did was to add a “wing” upon which we could beat at the same time as we applied torqueing force with a cheater-pipe-enhanced pipe wrench.  And that did the trick.  The nut came loose.  Then the coupler was removed – but only after the application of force provided by a local shaft-guru employing a hydraulic press.

 The rest of the story is anti-climatic.  A full two-weeks after the adventure began, the old stuff has been removed, the new shaft-seal stuff has been installed, and – of course – several rum punches have recently been consumed.  Now, in the midst of a storm of scheduled launches, we simply await our turn to be splashed, after which we will head back north toward Grenada and points further north.

 Special thanks to:

Fred Blockland and Tom Button, Kadey-Krogen Yachts
Hunter Sharp, s/v Arctic Tern
Steve Manley, s/v Receta

Troublesome nut on the end of the shaft -- inset into the shaft coupler

First tool, after fingers were reinforced

Drawing of "wrench" provided by Fred at Kadey-Krogen

Second (and successful) tool

Nut after its removal

Coupler after its removal

Tapered end of shaft after removal of coupler

New SureSeal kit -- sans hose clamps