transmission change

captain don · Post by **captain don** » Mon Aug 31, 2009 11:26 pm

When I bought my F-32 one of the transmissions was missing. The correct match is a 1:52 - 1 velvet drive. I have a chance to buy a matched pair of 1:92 - 1 at a good price. What will happen if I change the set up and go with the new ratio? Am I asking for trouble? Thanks, Captain Don

prowlersfish · Post by **prowlersfish** » Tue Sep 01, 2009 6:12 am

You will need more prop and you will be putting more torque one your shafts ( apox 20%)

LSP · Post by **LSP** » Tue Sep 01, 2009 12:55 pm

Paul .... would you "not go" that route?

jav · Post by **jav** » Tue Sep 01, 2009 1:16 pm

I like the additional reduction over the 1.5 gears for prop selection but- it will change your prop pitch requiremetns AND it will stress your shafts more.

I always cringe when I hear about a recent purchase and 1 bad Velvet drive gear... the Velvet drives were used quite extensively with counter rotating engines. I've heard of quite a few guys that replace counter rotating engines, but leave the old velvet drive gears... running one in reverse and eventually loosing that transmission.

Most Velvets installed in counter rotating applications have weaker reverse gears and can not be run in reverse at full load for long.

I'd be less worried about the ratio and more worried that the application is correct for your engine configuration..

prowlersfish · Post by **prowlersfish** » Tue Sep 01, 2009 4:37 pm

You can not run a velvet dive in rev. to change prop rotaion only a few velvet drines are made to revese the rotaion of the shaft . would I go that route ? if the shafts were up to it and I could clear the props needed I might do it . rember the deal could get costly as props are not cheap .

ready123 · Post by **ready123** » Tue Sep 01, 2009 11:42 pm

Have you checked Beacon Marine about Velvet drives?
They used to have used and rebuilt ones listed on the old site.... unfortunately they have updated the site and very little of value is left.

How can we support the site when they have no Trojan parts to speak of!

captain don · Post by **captain don** » Wed Sep 02, 2009 10:01 am

Thanks for all the replies on the transmission ratio question. I will be patient and wait for the right match to come along. I have plenty of time because my project is projected for two years. Captain Don

randyp · Post by **randyp** » Wed Sep 02, 2009 10:11 am

Try marinepartssource.com. I think they have what you're looking for.

Trojan Boat Forum

transmission change

transmission change

replies in transmissions