can anyone help me? Scarab, Kaama surface drives, velvet drives

Discussion in 'Surface Drives' started by hatterick, Jul 19, 2012.

  1. hatterick
    Joined: Jul 2012
    Posts: 9
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    Location: San Mateo

    hatterick Junior Member

    Hi guys, I purchased a 30 scarab with Kaama surface drives. The boat had no motors in it. I have the trans and v-drive combo with the drive shafts that run under the motor out the transom. I was told that the motors were 5.7 liter motors which I guess are 350 chevy motors. the motors mount backwareds (flywheel towards the bow) What I don't know is do they pick up the counter rotation from the motor or trans? if its the trans how can I find out which one goes to port and witch one to starboard? someone told me that the velvet drives that I have can be reversed by just turning around the pump. Has anyone heard of that? they are borg warners m71s I think. the v-drives and trans are one unit. looking at the back of the boat does the port side shaft turn clock wise and the starboard turn counter clockwise? or the opposit. is there anyway of turning the trans before attaching the trans to the motor. any one that can help me please tell me what to do
     
  2. IMP-ish
    Joined: Jan 2011
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    Location: united states of america

    IMP-ish powerboater

    Post some pictures if you have time. Would like to see your setup! Don't get the advantage of the v-drive shaft angle ??? and surface drive combo ???
    There are some threads here about which trans can be reversed easily and which can't.
     
    Last edited: Jul 21, 2012
  3. Frosty

    Frosty Previous Member

    deleted
     
    Last edited: Jul 22, 2012
  4. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Velve-Drive transmissions of the 70 and 71 series do not reverse the rotation of the engine. They should be dialed for the correct rotation or they will fail in a short time. The plate on the pump has a cast on indicator for the correct rotation. It says this side up and an arrow indicating the rotation of the input shaft.
     
  5. hatterick
    Joined: Jul 2012
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    Location: San Mateo

    hatterick Junior Member

    thanks for responding too my post, Problem. I've taken care of that problem by fabricating a plate that attaches to the trans v-drive combo and spinning them with half inch drill motor in a clock wise rotation. (indicating arrows on the trans) I now know witch tranny is standard rotation and counter rotation and witch one goes to port and starboard. I also know that both motors spen the same way. looking from the frount, clockwise as do all 5.7 liter small block chevys.
     
  6. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Velvet Drive transmissions should not be run in reverse continuously though. You need a reverse turning engine or run both props the same way.
     
  7. powerabout
    Joined: Nov 2007
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    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    you can get reverse rotation chevs
     

  8. Car Biz
    Joined: Sep 2012
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    Location: Grand Rapids MI

    Car Biz New Member

    Just joined today thought i try to help fellow KAAMA owners. the trans should be a TwinDisc MG 502 tranny not a BW with any type of V drive can you post a pic?
     
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