Water intrusion in stern thruster compartment

[Nutedog]

We have experienced stern thruster failure on Seaweed a 2012 28 foot Cutwater. The joystick would only activate the thruster while coming back to the center position for just a very short burst. Side power was very helpful with troubleshooting information. The results of this testing continued to point to dual joystick panel failure. Replaced panel with no resolution.

Ultimately it was conclude it was the thruster motor itself. Pulled thruster motor sent off to side power for texting come to find out unit had been exposed to water and was basically toast.

Upon further review it does appear there has been water in this compartment but it also looks like this area is designed to remain fairly dry but it also appears there may have been standing water about 2 inches deep enough to get into the thruster housing.

Boat sits on lift when not in use. In general bilge is very dry.

My question is what is the most likely path for water to get into this area. I want to solve this problem before I sacrifice another thruster.

Feedback would be appreciated.
Nathan

 

[bill46]

Our R31CB collects a couple of inches of water by Thruster and on Starboard side that require pumping with a hand pump.
Are there limber holes to the bilge bump under the shaft log?
The pump gets almost all out of the under shaft area, but a couple of inches remain by the stern on both sides.

Bill46
Radio Active

 

[nzfisher]

There is extensive history regarding water in the thruster cavity for Ranger Tugs. Some of the issues might be germane for the cutwater as well. Issues were conditions such as trailering with water in the cavity or trailering in the rain ( Boat not level with water in the cavity), plugged drainage hole leading from the thruster cavity, failed fitting from raw water wash down pump and more. Good luck. This seems to be an ongoing problem judging by the recurrence of posts.

 

[bill46]

Cleared limber tubes to rear, port dripped a little. Both seem above bottom of cavities. Got most out with a hand pump. Most bilge is quite dry, just an inch under the aft pump.