basic reverse rotation question

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   I think I know the answer here but, always double check with experts when possible.I have a 78 Southwind project, it had a Reverse Rotation OMC 350 with Velvet Drive. That motor is kaput!!!
I happen to have an 88 Baja with bad stringers and transom but a perfectly working, well maintained Mercruiser Magnum 350 that is standard rotation with a trs outdrive.
plan was to finish the Southwind, then start on the Baja but I have boat project and cost fatigue, the last thing I want to do at this point is finish one and start another.
So, Southwind with new stringers and deck, no motor...Baja with good motor and junk transom...
Everything has been stripped from the Southwind, could I put the Standard rotation Mercruiser in the Southwind and simply buy a Standard Rotation Velvet drive and put that in the Southwind??
Would use a good motor on a boat I am going to junk and probably save about 3500.00 on engine work.
sidebar- looks like a new (used) velvetdrive might be in the 1000-1500 dollar range for a net savings of a couple grand.
Ok boys, tear it apart..
As always, appreciate your help and input!!

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Brett Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: June-13-2019 Location: Columbus, OH Status: Offline Points: 90	Post Options Post Reply Quote Brett Report Post Thanks(0) Quote Reply Topic: basic reverse rotation question Posted: May-02-2024 at 12:32pm
	I think I know the answer here but, always double check with experts when possible. I have a 78 Southwind project, it had a Reverse Rotation OMC 350 with Velvet Drive. That motor is kaput!!! I happen to have an 88 Baja with bad stringers and transom but a perfectly working, well maintained Mercruiser Magnum 350 that is standard rotation with a trs outdrive. plan was to finish the Southwind, then start on the Baja but I have boat project and cost fatigue, the last thing I want to do at this point is finish one and start another. So, Southwind with new stringers and deck, no motor...Baja with good motor and junk transom... Everything has been stripped from the Southwind, could I put the Standard rotation Mercruiser in the Southwind and simply buy a Standard Rotation Velvet drive and put that in the Southwind?? Would use a good motor on a boat I am going to junk and probably save about 3500.00 on engine work. sidebar- looks like a new (used) velvetdrive might be in the 1000-1500 dollar range for a net savings of a couple grand. Ok boys, tear it apart.. As always, appreciate your help and input!!

samudj01 Members Profile Send Private Message Find Members Posts Add to Buddy List Gold Member Joined: March-10-2009 Location: NC Status: Offline Points: 946	Post Options Post Reply Quote samudj01 Report Post Thanks(1) Quote Reply Posted: May-02-2024 at 1:17pm
	I am far from an expert (and don't know chevy very well)... If both short blocks are the same, you could take the reverse rotation parts out of the southwind and pair them with all the good stuff from the baja. Pop the new RR engine in the southwind and you then have the correct rotation for the boat AND don't have to buy a tranny. Bet the switch may cost less than a new tranny as long as the baja motor doesn't need an overhaul while apart. Parts that need to come from the Southwind...cam, distributer, starter, and probably crank (depending on wick lines and seal availability). Now, if the southwind motor is toast, some of those parts may not be able to be reused, so that is at play too. If you are willing to go Std Rotation, I think there is a way to change your velvet drive...but that is over my head...someone else can chime in. I've read about it. That may be the cheapest and easiest solution.
	78 Ski Tique, 72 Skier w/302's, 93 SN w/351 & 17 GS22 w/zr409 Previous - 99 Sport Nautique w/GT40 and 87 Martinique w/351

GottaSki Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: April-21-2005 Location: NE CT Status: Offline Points: 3335	Post Options Post Reply Quote GottaSki Report Post Thanks(1) Quote Reply Posted: May-02-2024 at 1:25pm
	Wont need a different transmission, simply index its pump to std rotation. I wouldn't sweat about a Southwind spinning LH. You may have everything you need but a prop
	"There is nothing, absolutely nothing, half so much worthwhile as messing around with boats...simply messing." River Rat to Mole

Jonny Quest Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: August-20-2013 Location: Utah--via Texas Status: Offline Points: 2863	Post Options Post Reply Quote Jonny Quest Report Post Thanks(1) Quote Reply Posted: May-02-2024 at 5:32pm
	The older Velvet Drives can be indexed to spin standard or reverse rotation. Do a search here on CCF about indexing a Velvet Drive. As GottaSki says, you would need a lefty prop. Don’t know about bell housing fitment…. JQ
	Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum

KENO Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: June-06-2004 Location: United States Status: Offline Points: 10715	Post Options Post Reply Quote KENO Report Post Thanks(0) Quote Reply Posted: May-02-2024 at 6:57pm
	Before we get started here Brett......how's the security force doing? If you're going with the Mercruiser normal rotation engine, the transmission is easy like a couple of people mentioned. You'd be using the Mercruiser starter and flywheel and you'd need a damper plate to fit the flywheel. There were 2 different flywheels used, a 14 inch and a 12 3/4 inch so depending on your flywheel sizes in each engine, you might need a new damper. The Mercruiser uses a rubber mounted hub for driving the outdrive and not a damper plate like an inboard with a Borg Warner transmission. It's probably a good idea anyways considering the age of what you have now to get a new damper plate. You might need a new bellhousing too depending on flywheel sizes. The Mercruiser bellhousing is different for an IO so it's a no go but trying the OMC would be a good idea. Otherwise you can get an aftermarket one that will work. The OMC raw water pump has not much at all in the way of replacement parts available and you should probably consider a crank mounted Johnson F6-9B or one of the clones that are available Some Chevy people have done that swap pretty easily. The Mercruiser raw water pump won't work because it's in the lower unit on your engine. There are other minor things to consider, but this'll get you started on a plan and probably lead to more questions, so ask away If you have things apart enough to get sizes and be able to try the OMC bellhousing on the Mercruiser engine, post those results. I think you'll get lucky and have a 14 inch flywheel on both and the OMC bellhousing will fit with the Mercruiser flywheel and starter......maybe.

phatsat67 Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: March-13-2006 Location: Indiana Status: Offline Points: 6149	Post Options Post Reply Quote phatsat67 Report Post Thanks(0) Quote Reply Posted: May-02-2024 at 7:16pm
	Big V hull won’t care much about rotation. I’ve got a LH 351 in one of my BFNs for short term use and it’s fine. I’m light and it might have the slightest hint of RH lean with me in it at lower speeds but above 30 it’s as flat as my RH BFN.

KENO Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: June-06-2004 Location: United States Status: Offline Points: 10715	Post Options Post Reply Quote KENO Report Post Thanks(0) Quote Reply Posted: May-03-2024 at 7:49am
	Here are a couple of pictures of the same transmission, top one is the pump oriented for Reverse Rotation, bottom one is for Normal Rotation. The appropriate arrow points in the same direction that the engine rotates You remove the 4 bolts that you see and rotate the pump housing, then put the 4 bolts back in. You don't need to remove the housing, just rotate it. There's a big rubber square O ring that seals the pump to the housing.it won't rip or tear and doesn't need to be replaced unless it was already leaking

Brett Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: June-13-2019 Location: Columbus, OH Status: Offline Points: 90	Post Options Post Reply Quote Brett Report Post Thanks(0) Quote Reply Posted: May-03-2024 at 8:18am
	Hello Ken- you old salt!! Appreciate you asking about the security force, we are minus a member, the gal on the left in the pic has stood her last watch. She served honorably and is greatly missed but is still and always will be the commander of the watch. This is as always great help and I am very appreciative to you and all the members. I have not pulled the Mercruiser out of the Baja yet... just couldn't bring myself to pull the plug on her until yesterday when I decided she is now an organ donor for the Southwind... Too Be Continued.... I will definitely post up what you asked for when I get there.

KENO Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: June-06-2004 Location: United States Status: Offline Points: 10715	Post Options Post Reply Quote KENO Report Post Thanks(0) Quote Reply Posted: May-03-2024 at 12:13pm
	Sorry to hear about the pup. The project is plenty doable, you'll have some wire harness adapting also, so don't throw anything out till you're all done....well boat parts anyways

swilliams Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: June-26-2016 Location: Cincinnati,Ohio Status: Offline Points: 235	Post Options Post Reply Quote swilliams Report Post Thanks(0) Quote Reply Posted: May-05-2024 at 1:39pm
	Brettt, do you still have the Omc 350 and if so what is wrong with it? If it’s rebuidable, I might be interested. Steve
	1976 Martinique,350 Omc. 1975 Glastron/Carlson CV16,115 Merc.

basic reverse rotation question

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