V drive question

Fastjeff
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Re: V drive question

Postby Fastjeff » Tue Jul 10, 2018 6:32 am

Guess which one is a royal pain in the *ss to work on!

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

EWRice
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Re: V drive question

Postby EWRice » Tue Jul 10, 2018 12:34 pm

Fastjeff wrote:Guess which one is a royal pain in the *ss to work on!

Jeff


They are all a pain to work on! :lol:

To go back to the original post. The reduction gear is determined by 3 things: prop diameter, engine rated rpm and intended hull speed. Prop diameter is the biggest factor. Depending on the number of blades and blade design, the diameter will limit the speed the prop can turn. All props have a maximum blade tip speed (in feet per second) that they can turn before cavitation occurs. The new Acme props have been able to increase this for a given size. Hydrodynamics is fascinating stuff!
Muskegon Lake
1972 32' Express flybridge
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On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson

Hiramsaint
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Re: V drive question

Postby Hiramsaint » Tue Jul 10, 2018 4:31 pm

Thanks, I think I have it now. A Velvet drive has the engine facing forward with a tranny and a shaft going straight to the stern-is that correct?

EWRice
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Re: V drive question

Postby EWRice » Tue Jul 10, 2018 6:20 pm

Inline, conventional, straight drive are all names for drives where the transmission bolts to the back of the engine and has a prop shaft running through the bottom of the boat, through a strut, with a prop on the end.

Velvet drive, paragon, hurth, twin disc are all brands of transmissions. Some also make v drives.
Muskegon Lake
1972 32' Express flybridge
"AL13"
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson

Hiramsaint
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Posts: 14
Joined: Mon Jul 02, 2018 2:49 pm
Location: Hiram, Ga.

Re: V drive question

Postby Hiramsaint » Tue Jul 10, 2018 6:31 pm

Thanks, so much, for taking the time to explain this to a newbie.