Re: Bowthruster Gear Oil

Ian Park

Don’t know if it will help. Have you tried rotating prop by hand to get the shaft and gears turning? It may move the oil a bit. 
Ocean Hobo

On 10 Nov 2019, at 14:42, ngtnewington Newington via Groups.Io <ngtnewington@...> wrote:

Hi Matt,

That does make sense but this is not the first time I have changed the oil. I did it when I bought the boat in June 2017 in Grenada WI. As I remember, I just drained it and filled the reservoir. It was hot and the oil would have been thinner. It was quite cool this time and the oil more viscous…any other thoughts out there?

Amelia AML 54-019
On 10 Nov 2019, at 14:03, Matt Salatino via Groups.Io <helmsmatt@...> wrote:

I may be speaking from ignorance, but many lower units require removing the vent plug, and filling via a squeeze bottle from the drain plug, until oil seeps out the vent, installing the vent plug, an then quickly installing the drain plug.
This way, you fill from the bottom, and air is pushed out the top.


I On Nov 10, 2019, at 8:15 AM, ngtnewington Newington via Groups.Io <ngtnewington@...> wrote:

I recently hauled out and decided to drain the gear oil from the Bowthruster, the oil was good and not cloudy but after two years needed changing.

Then after replacing the oil drain screw filled up the oil reservoir with 90 weight gear oil. The problem is that the gear oil will not flow. There is obviously some kind of air lock. I managed to get about 250ml in by Blowing into the reservoir, i.e. pressurising it. 

I have now left the boat for the winter and maybe the oil will work its way down by gravity. 

I looked for a bleed screw to let the air out but found nothing. 

Does anyone know if there is a air vent bleed screw? Or is there some trick?


AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece

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