The port drive showing the newly added seal plate. This should stop water getting into the drive in the future.
On Friday, International Marine Diesel's lead tech, Neil, came on board and ran a bunch of diagnostic tests to try and work out what's going on. End result - better go for a sea trial. As a safe guard, Neil "shimmed up" the oil pressure relief valve on the port drive so that it would maintain slightly higher pressures. He wanted to be sure that when we went out, the drive wouldn't be starved for oil. It was getting late on a Friday, so we planned on doing that Monday morning.
On Monday, Neil showed up at 10 am, reasonable early by mechanic standards, and off we went. I'd been stressing over this all weekend and hadn't got much sleep Sunday night. as it turned out, the trip down the river was stress free and reasonably uneventful. The tide was coming in, so idle kept us going at a sedate 3 knots, which was fine by me, and I had plenty of time to react to oncoming traffic. The only boat of note was a 95' yacht. I was well prepared as I'd been listening to the captain talk to traffic ahead of us and the bridges. When he showed up around a corner, I had plenty of space to jockey aside. We were out in the ocean by 11. Nice and flat, the seas were less than 2' coming from the north east. I pointed her in that direction and we were off. Up to Wide-Open-Throttle and back a number of times as Neil used his little HP hand-held, plugged into one engine or the other, for data capture. we were able to get the port engine up to 3200 and the starboard up to 3400, but both engines overheated, showing 205 degrees coolant temperature. They should maintain 185, even at WOT. As for the drive, all though it showed low oil pressure at low RPMs, once the RPMs were above idle, the pressure came right back to normal. Once he'd got all the information he needed, we turned around and headed back. An uneventful trip up river and we were docked by 12:30. I moved Lucky into another slip, getting her closer to the shore and a stern-in, starboard tie-up, so I could put the tender back on the swim platform.
Neil came back on Tuesday and I got the full scoop. Both engines are over heating. Cause most likely due to heat exchanger fouling. Bearing in mind we replaced both fuel coolers for the same reason, it seem likely. So Neil had come to pull both heat exchangers, that use sea water to cool the engine coolant and both charge air coolers, that cool the compressed air going into the cylinders. As for the low oil pressure in the port drive, he didn't know and Volvo hadn't got back to him yet.
Meanwhile, I was having electrical issues. There was still a lose battery cable showing ground when it should show +12v and the generator wasn't starting up. An electrician came in Tuesday afternoon and we were able to solve both problems. The battery cable only showed ground when the "Helm C" breaker was on and further investigation showed that the spot light was the culprit. It's never worked right (always popped a breaker) and I've never needed it, so we unplugged it from it's breaker. I'll solve it another time or just pull the whole thing off. The generator needs a new emergency stop switch. The original was corroded. Another victim of salt water intrusion. To be safe, I replaced the breaker just above it as well. I had to order the switch, it should arrive next week.
The underwater lights were installed, but couldn't be tested as they were lacking the correct fuses.
To finish off a full day, I moved aboard. Stephanie would be horrified at the mess, but if you promise not to tell her, there's no reason why she should ever find out...
Not much happened Wednesday and Thursday, other than the electrician finding out that he needed insurance to work in the yard. I decided that if the engines were having all these issues with raw water cooling, then the A/C condensers were probably needing a little TLC as well, so I went out and purchased the makings of a flush system (hoses, pump, fuse, switch).
Today has been a busy day. Neil came back and took the transmission from the port drive. After pouring over schematics, they've decided the only way for the drive to show low oil pressure at idle but not at load is for one bearing in the main shaft to be leaking oil. The transmission is pretty trick, in that it used the oil pressure to engage the clutch and two channels in the drive shaft to move the oil up the drive to the top side of the clutch pack. At idle, when these channels are closed, there's only one thing maintaining pressure from the oil pump, and it's this bearing. So they're going to replace the bearing. It'll take over a day to replace the drive and the four coolers, so we're planning on another sea trial next Tuesday. All being well, everything will check out and I'll be off to CA with a lifted heart!
Once Neil left, I used my jury-rigged flush system to flush weak acidic solution through the raw water system of the A/C condensers. I flushed the acid through for 2 hours, then followed it with a fresh water flush. We have four condenser units, connected to two raw water pumps. Today I flushed the most important - the main cabin - and the other condenser attached to the same pump, the aft cabin. It meant turning the A/C off for the afternoon, so I retreated off the boat into "The Captains Lounge", a very nice lounge with TV, leather sofas, kitchen and wi-fi, while that was going on. Based upon the color the solution turned - a mucky brown - they needed the clean. I was able to reconnect the units correctly and turn on the A/C. It might be my imagination, but it seems a little more effective :-)
In other good news, the electrician finally showed up with the correct fuses and we were able to verify that they work! I look forward to seeing them in full glory later tonight.
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