Well, that has changed, finally. Two projects which have prevented the boat from moving are done. First, the compass binnacle and pedestal have been reassembled, and the throttle and gear shift levers are once again connected. Oh yeah, and everything is now spiffy-shiny.
Recursive project completed. |
The second project took longer. In fact, the compass binnacle was kind of a fill-in, since we were trapped at the dock and couldn't move anyway. This project was the exhaust hose failure - a much more difficult project. After removing the old hose, the next problem I ran into was that tho the engine exhaust elbow was 3" OD and the old hose (and thus the new hose) was 3" ID, the water lift muffler inlet was 2 7/8" OD. Undoubtedly this was because the muffler was a custom construction and 2 1/2" schedule 10 stainless pipe was used to make the inlet... that pipe is 2 7/8" OD, probably the closest to 3" they could get. I discovered this when I went to clean off what I thought was just some of the inner liner of the old hose from the inlet. Nope, it was some kind of rubber tape, wrapped around the inlet to fill the gap in diameters. It was also apparent that this was not the first solution tried - there was evidence of water leakage at the inlet, probably caused by an attempt to just clamp the daylights out of a 3" hose and try to squeeze it down enough to make a seal. Not.
I gave a lot of thought to this, how to match up the diameters. Finally, I settled on the approach the last mechanic had used - it has lasted successfully for 19+ years, after all. OK, so since the old rubber tape was gone, I needed a replacement.
I bought a 36" length of 2" wide, 1/32" thick, adhesive-backed silicone rubber tape. I chose the smaller thickness so that I could make two wraps around the pipe, minimizing a leakage path thru the joint at the ends of the tape. I wanted adhesive-backed tape because the inlet is almost inaccessible, and the tape would have to stay in place while I fiddled with installing the hose. And finally, I wanted silicone rubber because it has a much higher temperature tolerance (400°F +) than neoprene or buna N rubber.
Silicone rubber gap-filler tape installed |
Then all that remained was to "just" install the hose. Because it was the least accessible (and most fragile, I didn't want to mess up the silicone tape), I installed the muffler end first. That part was easy, being pretty much a straight shot. Everything got a good dollop of silicone rubber RTV too, just to seal any small gaps. Then tighten down the two hose T-clamps to stabilize the joint.
Next the hard part: wrestling the alligator - bending the hose and getting it onto the exhaust elbow. The hose is only slightly more flexible than a 3" tree branch. This part took blood, sweat, but thankfully no tears. And then two more T-clamps and the job was done.
Alligator: wrestled. |
I waited until the next morning in order to give the RTV time to cure and then started the engine. No leaks! Woo HOO!
So, by the time you read this, we will be out at anchor in the Islands somewhere.
Yeah!
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