Unknown Reservoir

[Harrysea]

While prepping the boat for Idalia, I noticed there’s a small fluid reservoir inside the frontmost compartment under the forward berth. Anybody know what it’s for?

 

[kirk a]

Is your boat equipped with a bow thruster?

 

[Harrysea]

Yes. I would never have associated it with the thruster. I didn’t see it on the bow thruster schematic in the Marlin manual.

 

[DogBone]

Is it possibly the hydraulic fluid reservoir for Bennett trim tab pump?

 

[Harrysea]

Is it possibly the hydraulic fluid reservoir for Bennett trim tab pump?

I’m pretty sure that reservoir is under the aft berth.

 

[kirk a]

There is a similar reservoir for the thruster on my 330.

 

[Automated14]

It’s bow thruster lube. Tube runs into the silver plate where the leg shaft runs through the tunnel. They deleted that on later models. . My ‘04 sidepower SP55S has it

 

[Harrysea]

is this something I need to change periodically? Seriously, I didn’t even know I had such a thing until three days ago.

 

[everwhom]

is this something I need to change periodically? Seriously, I didn’t even know I had such a thing until three days ago.

Yes, Imtra recommends changing every other year: https://www.imtra.com/learning-center/articleid/40/bow-thruster-maintenance . Of course for many years, I had no idea I was supposed to do this, and when I did ask my marina to change it we discovered that the gear leg was in pretty bad shape so we replaced it with the newer version that doesn't require the oil reservoir at all.