Reverse rotation engine question ...
#13
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Originally Posted by boot
Hey Bigyellowcat, You didn't change anything in the bottom end ? What about the seals ?
How much time do you have on them now ? Thanks for your reply !![Cool](/forums/images/smilies/cool.gif)
How much time do you have on them now ? Thanks for your reply !
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#15
Michigan Mad Man
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one thing you need to do is polish the crankshaft in the direction of rotation because when polishing the crank it raises the metal and you do not want your oil flow going against the raised metal. Tyler
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Merc and most marine builders reverse their crankshaft rotation but maintain normal cam rotation by using a gear rather than chain drive. That way you can use a standard distributor/oil pump setup. Cam is a different grind. The crankshaft p/n for merc is the same on left vs right rotation, so that doesnt seem to be an issue. Pistons and rods are also the same p/n. I've heard about reversing the pistons on older engines, not sure about that though. Only the rear seal is different, yellow instead of blue. Although there are people on this board using the wrong seal without problems. Front seal is the same.
That being said, Bigyellowcat pointed out you can reverse the rotation of both the crank and cam with a few modifications.
I hope formula31 can shed some light on piston direction.
Gary
That being said, Bigyellowcat pointed out you can reverse the rotation of both the crank and cam with a few modifications.
I hope formula31 can shed some light on piston direction.
Gary
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Originally Posted by Gary Anderson
Merc and most marine builders reverse their crankshaft rotation but maintain normal cam rotation by using a gear rather than chain drive. That way you can use a standard distributor/oil pump setup. Cam is a different grind. The crankshaft p/n for merc is the same on left vs right rotation, so that doesnt seem to be an issue. Pistons and rods are also the same p/n. I've heard about reversing the pistons on older engines, not sure about that though. Only the rear seal is different, yellow instead of blue. Although there are people on this board using the wrong seal without problems. Front seal is the same.
That being said, Bigyellowcat pointed out you can reverse the rotation of both the crank and cam with a few modifications.
I hope formula31 can shed some light on piston direction.
Gary
That being said, Bigyellowcat pointed out you can reverse the rotation of both the crank and cam with a few modifications.
I hope formula31 can shed some light on piston direction.
Gary
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If you reversed the oil pump, what would that do to it's flow?
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I was wondering if that was why his buddy took out his crank bearings...