Water in stern thruster compartment

[Just Limin']

After heavy rain storms, water somehow gets into my 2012 25SC's stern thruster area. This has already once damaged the unit and I had to replace it. I've tried everything, but water gets in there. I'm not sure how. The weep hole at the bottom of the area is open but it never drains out. I've covered the seat with a tarp, and water gets trapped in there, but somehow it is finding the thruster area. We get lots of thunderstorms in Southwest Florida, and I'm not going to go through the expense of another thruster. It's driving me nuts! Maybe I have to put my head down there during a storm to see where it comes from and just hope I don't get struck by lightning!

 

[ALICE J]

In my R27 I put a yellow Whale automatic pump, worked for a little while then the submersible pump rusted and froze, replaced the pump with another dumped the water into the bilge, but am thinking of filling the void with spray foam, placing a piece of plastic on the bottom and around the motor too so if the motor had to come out, I would only have to dig out the foam as it would not be suck to the boat or motor.

 

[tlkenyon]

I think I had the same problem. I have been told that the motor for my stern thruster had water damage, but the drain in the compartment was always clear. I wonder about drilling a new drain hole in the very bottom of the compartment so that absolutely NO water can accumulate....but would hate to drill a hole in the hull....

It is interesting how a vapor-tight "ignition protected" motor can get water damage. Vapor tight but not water tight?

TK

 

[Red Raven]

The weep hole at the bottom of the area is open but it never drains out.

I don't think it is possible for the weep hole to be open and not drain unless your boat is really stern heavy. And even then it would be just a bit of water nowhere near the level of the thruster. The weep hole must have an obstruction. Clear it out with a stick or rod then test it with a hose. If it doesn't drain clear it again. If necessary, force water through in reverse. It took me several tries to really get it to flow. There can be lots of fiberglass combs in the weep holes that collect stuff. You can also clear it with a really long drill the same size as the weep hole if you are really courageous!

The water gets in through the seat and underseat compartment and always will.

Curt

 

[blifland]

Our 2011 RT25SC had water leaking into the stern thruster cavity when boat is in the water.
Installed a temporary auto-bilge pump till I could find why leaking. (attached pump to 1/2 x 36 inch plastic pipe with radiator clamps; powered from the raw water wash-down pump switch as I do not use the wash-down pump).
Ranger Tug fellow found the leak at 2016 Rendezvous, several of the 6 bolts securing the thruster tunnel were leaking. He recommended replacing and re-caulking all the bolts.
With boat on trailer, pulled all 6 bolts. No caulk on any of the 6 bolts and 4 of the 6 were twisted or bent, with some corrosion and metal missing. Put in new hex-head bolts - with plenty of 4200 and secured with bolt heads on the water side and nuts on the inside as I was single handing this adventure. Note - if you can get two thruster wrenches - makes it easier to remove the two motor allen-head bolts - must keep pulling motor back as you unscrew each side a little at a time.

Since I had the thruster motor out (easy to disconnect the cables) I added two
u-bolt plates to the thruster motor - on two of the bolts securing the housing/gasket; using just two nuts on the bolts, without undoing anything. Used the 10 and 2 o'clock position bolts.

Put a rope between the two free ends of the plates and the motor was perfectly balanced (an unexpected surprise)- making it easier to replace the motor (attached the rope+motor to a 1 inch webbing (carabineer) which was secured to a 1.5 inch board - laying on the fiberglass 'railings'. Webbing runs sandwiched between another u-bolt plate and the board, so I could adjust the length of the webbing, to lower the motor to correct position. (u-bolt plate was bolted to underside of the board - easy to loosen/tighten webbing)

As for vapor protected housing leaking; my red gasket in the housing was starting to crumble - would not be surprised if not 100% working/intact anymore.

Boat is still on trailer - so I do not know if leaking is fixed - will keep the auto bilge pump a while longer and will keep the rope on the motor forever.

 

[Just Limin']

Boat is on our lift the majority of the time. Has to be rain water. Maybe I just need to move to the desert?

 

[tlkenyon]

Our R25sc is on the trailer most of the time, and our stern thruster motor failed because of water intrusion, despite actions to try to prevent this apparently recurrent problem. I asked the factory and did not receive a very good response on future prevention of this problem.

Somehow, this needs to be figured out. Maybe a more effective drain and an raincoat?

 

[Brian B]

My 25SC sits on the trailer in the off season. I keep the trailer in a somewhat level position, the stern thruster area holds about an inch of water and drains into the bilge. I run a snake up the drain holes to make sure they are clear.

 

[tlkenyon]

I have the same issue...and I make sure the drain holes are clear. Maybe is there a way to keep ANY water from accumulating? "Lowering" the drain hole?

 

[plewis]

In my opinion blaming the inch of water in the rear thruster compartment for thruster motor problems could be a mistake (unless a portion of the thruster is continuously submerged). I too have had an inch of water in the compartment and have had thruster problems, but the problem was with the motor solenoid. I suspect the weak link in the thruster system is burnt pitted contacts on the motor solenoid due to poor design. I say poor design because in 50 years of car ownership I have never a starter solenoid problem, and the starter solenoid performs the same function at similar current levels as solenoid in the thruster.

I would suggest that if your thruster's problem begins intermittently - failing to go in one direction reliably then totally failing - checkout Sidepowers troubleshooting guide for info regarding the solenoid.

http://www.imtra.com/Collateral/Documents/.../SP_Troubleshooting_Guide_with_IPC.pdf

 

[Just Limin']

Performed tests today to make sure my water lines from the cockpit scuppers were not leaking. They are not.
Filled the thruster compartment up with about 2-3 inches of water to see if it would drain into the bilge from the compartment. It did, but soon stopped, leaving about a half gallon of water in the compartment.
It must be coming in during the hard rainstorms. Can't figure out from where. I've put a tarp around and over the seat, but it's still getting in. I guess I'll have to live with it, believing that it will drain when it gets above the two inches.
Ranger might think about lowering the drain hole closer to the bottom and increasing the diameter of the hole to about 1/2 inch. The joy of having the boat on a lift right behind the house, is that I can easily check it. I just have worries that the thruster might again need to be replaced....
Thanks for everyone's suggestions..

 

[tlkenyon]

My stern thruster motor is out for repair, so the compartment is highly accessible. If I drilled a drain hole in the very bottom of the compartment, would the drainage go directly into the bilge? Seems like a possible solution, but would hate to damage something....

Tk