Bow Thruster Prop and Maintenance

[nveater]

I have a 1999 vintage Side Power 4hp bow thruster that has been working well. For a boat Christmas present, I bought the boat the new Sleipner 5 bladed Q prop upgrade kit. The prop is alleged to have more thrust for less power. In looking at videos on the internet, it seemed a fairly easy job of removing the prop- get a appropriate size socket wrench to remove the retaining nut. However on actually visiting the boat I see that there is a hub on the prop and what appears to be a set screw on the side. I am going to assume that the set screw is how I remove the prop- before I attack this I wanted to find out whether anyone else in the community has done this and am I on the right track. Second question was, with the prop off, I might have access to the oil drain screw on the bottom of the unit and I thought I would try changing the gear oil- again would appreciate hearing from someone who has done this and any helpful hints

 

[Comodave]

I just found a video on YouTube by Imtra that shows how to remove the prop. They said it is the same until you get to the large thrusters. Remove the ande with an allen then remove the prop nut with a metric socket. There is a special washer behind the nut. Looks pretty easy. I didn’t look for an oil change video but there might be one for that also.

 

[Comodave]

Just looked at oil change and this is what came up.

Changing oil in a Side-Power thruster depends on the model;
older ones with a feed tube have a simple top-off process with EP90 gear oil, checking the tube for milky (watery) oil first, while modern sealed units need no oil change, but all thrusters need yearly checks, cleaning, and anode replacement, often involving removing props and checking/greasing shafts

 

[nveater]

Thanks I have seen those- however my anode is opposite my prop and there is a cap or hub over where the prop nut is on the newer models. I'm trying to find out how to take the prop off with the cap

 

[Comodave]

Ok, then I would call Imtra and ask them. They were very supportive when I had a Side Power thruster.

 

[nveater]

Thanks shall do

 

[nveater]

Just as a follow up- I have emailed the nice folks at Imtra and they confirmed that to take the prop off there is an allen key fitting on the side- remove the screw and then wiggle like heck- there appears to be decent clearance on the side of the prop so when the weather warms a bit we'll try it out