WhippetGood
Member
I have more to write about the 're-power' of the Greenline 48, but that's in another thread and happened years ago - so have to dig deep. However, the most recent 'excitment' is near to mind, and was just resolved - so I figure I would post about it in case anyone wants to check their stern thruster (for any boat I suppose!)
We purchased the boat used in 2018, and it's a 2016 Greenline 48. It came with Bow + Stern thrusters, which I have greatly enjoyed using. I came from a boat without any thrusters, and although I can run the boat without them (and had to, recently) there is nothing like going perfectly sideways or counteracting a strong wind or current with a smash of the button. Whatever the case, however you captain - this isn't about the use of the thrusters.
Anyway, after moving the boat up to San Juan Is. WA in 2021, we had more rain on the boat than it's ever seen. We had some minor leaks - likely screws through the teak into the fiberglass, or sealant failing around the window - but we had water in the bow cavity, which would make it's way back when cruising. Even with the bilge pumps, some water would make it back to the engine compartment, and then back to below the Lazerette where it filled a small area below the thruster motor inside the boat (the propulsion parts being outside the stern below water). This standing water contacted the positive because the Stern Thruster was installed upside down, such that the positive terminal was at the bottom.. we found this out after the Stern thruster failed. That's when we began to worry that the problems were bigger (they were) because the water was energized if the thruster had power and electricity was contacting the bolts connected through the hull to the external part of the thruster.. and escaping the boat.
The terminal bolt was powdered rust (it just broke when touched) and the through hull bolts were also completely corroded.
The bigger problem was the Shafts + Props. They were extensively damaged (the Zincs were fine!)
here is a picture of a piece of the shaft after extraction:
So..this was a slow then fast process. We never noticed because the stern thrusters are so rarely in operation AND we had to have some water in the area of concern. But once it happened, the amount of voltage must have been high (thrusters thrusting) and the damage was extensive. I'll post more pics and the fix in a followup post later.
Check your stern thruster!
cheers
Chris
We purchased the boat used in 2018, and it's a 2016 Greenline 48. It came with Bow + Stern thrusters, which I have greatly enjoyed using. I came from a boat without any thrusters, and although I can run the boat without them (and had to, recently) there is nothing like going perfectly sideways or counteracting a strong wind or current with a smash of the button. Whatever the case, however you captain - this isn't about the use of the thrusters.
Anyway, after moving the boat up to San Juan Is. WA in 2021, we had more rain on the boat than it's ever seen. We had some minor leaks - likely screws through the teak into the fiberglass, or sealant failing around the window - but we had water in the bow cavity, which would make it's way back when cruising. Even with the bilge pumps, some water would make it back to the engine compartment, and then back to below the Lazerette where it filled a small area below the thruster motor inside the boat (the propulsion parts being outside the stern below water). This standing water contacted the positive because the Stern Thruster was installed upside down, such that the positive terminal was at the bottom.. we found this out after the Stern thruster failed. That's when we began to worry that the problems were bigger (they were) because the water was energized if the thruster had power and electricity was contacting the bolts connected through the hull to the external part of the thruster.. and escaping the boat.
The terminal bolt was powdered rust (it just broke when touched) and the through hull bolts were also completely corroded.
The bigger problem was the Shafts + Props. They were extensively damaged (the Zincs were fine!)
here is a picture of a piece of the shaft after extraction:
So..this was a slow then fast process. We never noticed because the stern thrusters are so rarely in operation AND we had to have some water in the area of concern. But once it happened, the amount of voltage must have been high (thrusters thrusting) and the damage was extensive. I'll post more pics and the fix in a followup post later.
Check your stern thruster!
cheers
Chris
