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slowjoe
09-08-2005, 07:03 AM
just bought a 73 marlin v drive and the drive runs off the front of the motor.
has anyone seen this before? just dosnt seem strong enough not being on the fly wheel side its my first v drive boat so i dont know.
i cant find pics of one like mine. any input would be great
thanks :

V-DRIVE VIDEO
09-08-2005, 07:20 AM
just bought a 73 marlin v drive and the drive runs off the front of the motor.
has anyone seen this before? just dosnt seem strong enough not being on the fly wheel side its my first v drive boat so i dont know.
i cant find pics of one like mine. any input would be great
thanks :
The following boats run off the crank snout with no problems....
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/10001/Conant.jpg
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/10001/Billy.jpg
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/10001/normal_lance.jpg
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/10001/Me%20001.jpg
http://www.v-drivevideo.com/jerrysgallery/albums/userpics/10001/Skip%201.jpg

Sleek-Jet
09-08-2005, 07:20 AM
I'll let some of the more knowlegable guys here give you the specifics, but yes, V-drives are driven off the "front" of the crank shaft all the time. Usually because they were rigged for a specific application, like circle racing.

lucky
09-08-2005, 07:38 AM
now why would one end of the crank be any weaker than the other :confused: --

GofastRacer
09-08-2005, 07:38 AM
Just make sure you have a keyway cut in the crank, double keyway with a blower!..

haulina29
09-08-2005, 08:09 AM
Its not necessarly what end of the crank is stronger but what is the strenghth of the main caps , rear versus front .

slowjoe
09-08-2005, 11:49 AM
Just make sure you have a keyway cut in the crank, double keyway with a blower!..
thaks for the info

Norseman
09-08-2005, 12:54 PM
now why would one end of the crank be any weaker than the other :confused: --
Lucky;
They run off the front "Damper" end of the crank because the boat is usually designed for circle boat racing. The torque of the engine helps the boat turn left faster.
The flywheel end of a crank isn't any stronger, bearings are the same dia on both ends!!

obnoxious001
09-08-2005, 02:03 PM
Its not necessarly what end of the crank is stronger but what is the strenghth of the main caps , rear versus front .
If you get right down to it, the crank snout is smaller diameter, and there is more leverage on that smaller diameter part if there is any kind of side loading. The rear crank flange is very close to the wide rear main bearing, at least on a Chevy. The circle boats do run the engines that way most of the time, as far as I know, mostly to allow the prop torque to make the boat turn better to the left, instead of wanting to pull the boat to the right.

Moneypitt
09-08-2005, 09:50 PM
Actually the right hand rotation of the prop does pull the back of the boat to the right. It helps like a paddle wheel, as the driver is pointing the front to the left, the prop is kicking the ass end around. You could circle race a boat with a left hand rotation, but it would not turn as well as the right hand prop rotation. I have been to quite a few circle races, and have never seen one driven off the flywheel, unless it is a CJ (jet)...........Moneypitt (from BHC)