SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: trihulljetman on March 20, 2013, 04:35:56 PM
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I was just wondering if any one new if you could chamge a LH roation motor to RH. I have a good motor in my ski boat and I want to put it in my jet. It has a jacuzzi yj pump on it. If you can does anyone now how to do it.
Thanks guys
Mario
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I was just wondering if any one new if you could chamge a LH roation motor to RH. I have a good motor in my ski boat and I want to put it in my jet. It has a jacuzzi yj pump on it. If you can does anyone now how to do it.
Thanks guys
Mario
Depends on how it was set up to run reverse rotation. Some use specially ground cams, with opposite ground Dizzy gears, advance mechanisms, and special oil pumps, etc. Others use just a special large cam/crank gear drive (no idlers, cam and crank gear meshed directly together) so that only the crankshaft ran backwards. Dizzy, Cam and oil pump operate in the same direction as normal.
Best to pull the timing cover and see exactly what you are dealing with. If it's got a a straight gear drive in there, probably only need to change it to a regular timing chain set-up, new main seals (They are different than regular ones, usually, and easy to change at this point anyway), and retime your ignition and make sure the firing order is correct. If it doesn't, would be a lot of parts swapping with the cam, oil pump, dizzy gear (Or the entire dizzy) etc.
Ray
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Saw a cracker box with tge motor in backwards and the driveshaft was hooked up to the harmonic dont know how yours is but it would assume thats just a matter of turning it around
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ok just so you understand about engine rotation, the block pistons crank heads carb intake , none of those care about which direction the engine rotates. the cam and the distributor gear are the only ones that care. you also have to be careful at where they want you you to view the motor from. a car you view from inside the drivers seat! a boat is viewed from the back of the transom( outsidethe boat) hope that helps.
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ok just so you understand about engine rotation, the block pistons crank heads carb intake , none of those care about which direction the engine rotates. the cam and the distributor gear are the only ones that care. you also have to be careful at where they want you you to view the motor from. a car you view from inside the drivers seat! a boat is viewed from the back of the transom( outsidethe boat) hope that helps.
Well, the oil pump cares also, but yes, pretty much it. Back years ago, Smokey Yunick used to make kits to run Sprint Car engines backwards, so did Isky. Don't remember why they did, but they aren't allowed to do that any more.
What I was trying to say, and hopefully clearer this time, was they used an oversized, helical cut crank gear and an oversized, helical cut cam gear that meshed together. No chain. Timing it all differently for reverse rotation. Crank went backwards, but cam/dizzy/oil pump went forwards requiring no special parts other than the timing set, it's cover maybe, and main seals (can't remember why on those, but probably just how they used to be made).
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ah! yes forgot the oil pump.
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They turned them around to use the rotation of the motor to help weight transfer like when u stab it and the boat twists
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Why would you run a 302 anyways?
I would attempt to sell the motor and use the money to finance a big block.
You will need a bunch of parts to get that Wakesha to work properly.
You never know with a reverse rotation motor, sometimes they bring a pretty penny.
Advertise it in the Boat Trader.
Just my humble opinion.
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THANKS GUYS. I DONT HAVE THE MONEY RIGHT NOW TO PUT A BIG BLOCK IN IT. I WOULD LOVE TO DO THAT BUT THEM I HAVE TO GET NEW MOTOR MOUNTS. I KNOW THAT 302 IN MY SKI BOAT IS BUILT WELL. MY PUMP ISENT UP TO PAR EATHER I NEED A NEW WEAR RING AND MAYBE A IMPELLER. THANKS FOR ALL THE HELP GUYS