A Tale of Two Chemists: The dripping ‘dripless’ seal

The dripping ‘dripless’ seal … 20th November 2012

We departed from the Frederica River this morning and motored around the top of Lanier Island down the Mackay River and around into the Brunswick River. We passed under the huge Sidney Lanier Bridge and up the “East River” to a slip at the Brunswick Landing Marina. Mike set to work on replacing the seal on the prop shaft that is water-cooled and meant to be dripless. This went really well and having completed the job he was very energized and keen to describe the details to the lady who runs the dock. He was half way through when her eyes glazed over and she said in a kindly way… "do I look like I'm interested in hearing this"! Un-phased Mike went to find someone else to tell the story to. See pictures and details below.

Being at a dock seems like such a treat. We did laundry, had showers and Mike cut his hair. We filled the water tanks, washed out the bilge, washed the decks. [The deck washing was soon undone. The local birds seemed to act like Thanksgiving had come early in the shape of a new boat on which to crap.] I found myself wondering why the dock seemed quite so exciting. I looked back through the log book to discover that we had spent the previous thirteen nights at anchor. That’s why being at the slip seems so special.

We are hoping to have a nice Thai meal in town. I do find myself wondering about the town. The lady at the marina drew a big X over half the town saying “don’t go into this area after dark!” A chap we had met a few nights ago described Brunswick as “run down”. I had mentally translated that to mean “it’s a dump”. Well the town does seem a bit run down, but the Thai dinner was excellent.

Gloria

31 09 03.4 N, 81 29 58.6 W

The dripless "strong seal" is at the left end of the blue tube. The spare seal is already mounted on the shaft and protected by the black casing clamped just to the right of the Aquadrive anti-vibration unit. I eased out the helical retaining clip at the end of the "strong seal" with a screw driver and then managed with some difficulty to pull out the old seal, using a fish hook, self tapping screw and needle nose pliers ... in that order! The old seal was then cut off the shaft.

The new seal is uncovered by unclamping the black housing and then slid along into place. The housing is then lightly clamped back on the shaft to act as a tool to press in the new seal. This was accomplished by tapping (hard) with a hammer wrapped in a rag. Finally the stainless steel helical clip is put back in and the spare casing / tool is removed. The whole thing took about half an hour - less time than it took me to find someone who was interested in hearing about it afterwards!

Seriously, what a fantastic design and incredible forethought to have the system in place for a seal that has an advertised life of 3000 engine hours.