
ngtnewington Newington
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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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Matt Salatino
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. ~~~⛵️~~~Matt
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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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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ngtnewington Newington
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?
Nick
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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. ~~~⛵️~~~Matt 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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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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. Ian
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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?
Nick 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. ~~~⛵️~~~Matt 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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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Paul Dowd and Sharon Brown
Nick, I filled mine from the top, with the drain open, then used a dinghy pump to pressurise the reservoir until clean oil came out the drain. I did need a few periodical top-ups but never had any problem with the bowthruster. Cheers, Paul S/Y Ya Fohi - Amel 54 #98
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From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of ngtnewington Newington via Groups.Io Sent: 10 November 2019 10:43 To: main@AmelYachtOwners.groups.io Subject: Re: [AmelYachtOwners] Bowthruster Gear Oil 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
-- Cheers Paul Ya Fohi - Amel 54 #98
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Nick,
Ahh, so it has finally cooled off in Greece. But what a nice October we had this year eh? As you have already suspected I am sure that the difference in the flow of the oil is just the viscosity has increase from the temperature. This is the same reason that changing engine oil with the engine warm, much easier. In the future if you have the same problem, just put some gentle heat on the unit such as a 100 watt clamp light or a small thermostatically controlled heater (in a pinch a hair dryer, but keep an eye on these things, not rated for continuous use) . No need to get anything really hot, just bring the oil up to 100F or so and it will be much thinner and should flow. It might take hours of gentle heating to accomplish this, especially if the 54’s have fibreglass cases on the lower units of the bow thruster which does not conduct heat very well. Hope you also had a good season in Greece this year.
James SV Sueno Preveza, Greece Also now high and dry..
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On Nov 10, 2019, at 9:15 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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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ngtnewington Newington
Thanks James and everyone else. I am home in the UK for the winter. October was gorgeous in Greece. The sea was warm enough to swim and the air pleasantly warm in the day and almost chilly at night.
Amelia is ready to launch, but it will be a long winter in the UK.
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On 11 Nov 2019, at 13:09, James Alton via Groups.Io < lokiyawl2@...> wrote:
Nick,
Ahh, so it has finally cooled off in Greece. But what a nice October we had this year eh? As you have already suspected I am sure that the difference in the flow of the oil is just the viscosity has increase from the temperature. This is the same reason that changing engine oil with the engine warm, much easier. In the future if you have the same problem, just put some gentle heat on the unit such as a 100 watt clamp light or a small thermostatically controlled heater (in a pinch a hair dryer, but keep an eye on these things, not rated for continuous use) . No need to get anything really hot, just bring the oil up to 100F or so and it will be much thinner and should flow. It might take hours of gentle heating to accomplish this, especially if the 54’s have fibreglass cases on the lower units of the bow thruster which does not conduct heat very well. Hope you also had a good season in Greece this year.
James SV Sueno Preveza, Greece Also now high and dry.. On Nov 10, 2019, at 9:15 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?
Nick
Amelia AML 54-019 ashore at the Bazimakoplou boat yard Kilada Greece
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