Friday, October 29, 2010

Back on the hard...

 As we reviewed the situation yesterday, we said out loud, "this is really gonna suck". Anyway it is what it is and Freedom is back up on the hard. We're not sure what the cause of the issue is, but it's better to get it resolved before we leave this marina and travel on risking more damage. Misaligned or bend shafts can lead to other failures that raise the cost of "poker".
 So what happened?
 At idle in gear tied down at the dock the port side propellor shaft was visably oscillating. One could look at the shaft seal and see it wooble quite a bit even at low speed. Good thing I checked it before we left.
 We're not sure yet but we suspect one of two things happened on the port side. The flange attached to the propellor shaft that mates the shaft with the transmission is warped or, the shaft is bent. I installed new shaft seals prior to the launch. That entailed separating the transmission and propellor shaft flanges, removing the flanges from the shafts, installing new seals, and then reattaching everything. The port side flange was a bear to remove from the propellor shaft. Quite a bit of pressure on the "gear puller" was required before it popped loose. That could have warped 1/2 inch steel. Tough to imagine I could do that with a few bolts while using a pattern of tightening to distribute the load but it's certainly possible. 
 Part of the process of reinstalling all of this was to hand lap the shafts into the flanges again. They are a self locking tapered fit with a key. While this was a chore considering the flange weighs about 15 pounds it all looked good. I should have stuck a dial indicator on it though. We all believe this was not the source of the issue. The pros removing everything this time have no explanation.
 So the running gear went to a shop for examination with all sorts of high tech gear and lathes. While all of this is happening we are dumping the GFO packing and Buck Algonquin spud type seals for Tide Marine dripless seals. Even though we were only idling at the dock in gear I could not get the temperature of the packing fittings on the shaft below a very hot to the touch temperature. Perhaps with two coils instead of three we'd get the temperature down but all recommendations were for three. Even with a large gap between the ends allowing for expansion on the starbord side, they both ran hot at a very loose setting of the spud.
 Fortunately we have great people around us here at Indiantown Marina. I can't say enough about them.

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