Re: Mercury Command Thrust Gear Case for ProXS 115

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jimh
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby jimh » Thu Apr 23, 2020 1:28 pm

I am not expert on Mercury engines, but my interpretation of their website is the 115 ProXS is available only in one gear case. The Command Thrust gear case is only available as an option on the FOURSTROKE 115.

https://www.mercurymarine.com/en/us/engines/outboard/compare/

The specifications mention:

Gearcase ratio
115 ProXS = 2.07:1
115 FOURSTROKE = 2.07:1 or 2.38:1 (CT model) [i.e. CT means Command Thrust]

The engine weights are also listed differently for an engine with a Command Thrust gear case, but the 115 ProXS is listed with only one engine weight, and it is the same weight as the FOURTROKE 115 without the Commmand Thrust.

If my interpretation of the Mercury website is correct, then the 115 ProXS is available in only one gear case, and that is apparently not the Command Thrust gear case.

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GoldenDaze
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby GoldenDaze » Thu Apr 23, 2020 4:40 pm

Ultimately I don't know that [choice of standard gear case or Command Thrust gear case on a 115-HP Mercury FOURSTROKE engine is] going to matter.

I have never really understood the point of the "Command Thrust" gearing anyway; you can accomplish the same thing by reducing propeller pitch by 2-inches. Looking at it the other way, if you were using a 16-pitch propeller with the standard gear case and you changed to a Command Thrust gear caset, then you would probably want to switch to an 18-pitch prop for essentially equal performance.

-Bob
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jimh
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby jimh » Fri Apr 24, 2020 6:28 pm

BOB--perhaps the Command Thrust gear case has a larger propeller aperture and a larger diameter gear case bullet, and the Command Thrust gear case can use a different series of propellers than the standard gear case found on the ProXS 115.

The ProXS appears to be marketed on the basis of being used on fast boats, and the notion that the ProXS would not offer a larger, heavier, and different gear ratio gear case intended for use on heavier and slower boats seems consistent with that marketing.

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GoldenDaze
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby GoldenDaze » Sat Apr 25, 2020 10:03 pm

perhaps the Command Thrust gear case has a larger propeller aperture and a larger diameter gear case bullet


Hmm, good point, I hadn't thought about that.
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Lupi
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby Lupi » Mon Apr 27, 2020 5:14 am

I confirm that Command Thrust has a large gearcase 4.75-inch diameter instead of the small gearcase 4.25-inch diameter on standard 115 FOURSTROKE.

Also, even if it is not clear on the Mercury website, both 115 FOURSTROKE and 115 ProXS are available in small gearcase and large gear case (CT).

The SEA PRO model for the 115 is only available in large gearcase.

jimh
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Re: Mercury Command Thrust Gear Case for ProXS 115

Postby jimh » Mon Apr 27, 2020 7:06 am

LUPI--thank you for the new information. Websites are often created by people who are familiar with web site creation, and those people may not be very familiar with the Mercury product line.