When our welder, Elvis, first brought the tank back, he claimed he pressure tested the tank and it was fine. My biggest mistake was to take him at his word. I installed the tank, added fuel, and a short while later it leaked. I nearly blew my stack as it is a real chore to get the tank back into its tiny hole.
After draining all the fuel into jerry jugs, I pulled the tank out again, and I insisted that Elvis repair the tank the way I asked him the first time; he needed to weld a plate on the bottom to cover the entire suspect area. When the newly plated tank came back to me, I placed it up on blocks and filled it with fuel, allowing it to sit on shore for 48 hours before going back into the hole. I shook the tank, front to back, side to side, trying to place additional strain on the seams and welds. With no signs of any leaking, I again drained the fuel, and with the help of Devin from Moosetracks, we stuffed the tank back into the hole. I added fuel and we waited.
In the above photo you can gain some understanding of why the tank developed a leak. The entire weight of the full tank rests on two frames, one front and one rear, each topped with a plywood bunk. The tank angles slightly towards the front, and over the years minimal movement caused the front six inches of the tank bottom to wear eventually opening a small crack. To help prevent this situation from recurring, I added a 1/8″ padded vinyl liner on top of each bunk; of course, I had to build a new bunk to sit on the forward frame as the original plywood was saturated with fuel and deteriorated.
With 32 gallons of fuel in the tank, we waited another 5 days to be reasonably confident the tank was not leaking. Breathing a tentative sigh of relief, we made plans to re-install the engine. I knew that was going to be a major undertaking. I made arrangements with the yard for the crane, lined up Devin and Liz from Moosetracks, and Disco, our boatman, as helpers.
On Thursday the 1st of Feb, only two weeks after removal, the engine slid back into its home. I could not believe our good fortune when the engine slid easily down over the front mounts, and, when I squeezed in between the lifting cable and the bulkheads, I discovered the rear mount brackets were perfectly aligned with the engine mounting holes. Whoopee!
Devin and I screwed the 6 bolts into the motor mount bracket holes with me squeezed on top of the engine and Devin squashed into the lazarette working the bolts on his side. In short order, all mounts and bolts were installed, and we sent the crane on its merry way, less than an hour all told.