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Starboard engine

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Nhodges1

New member
So I’ve got a 35 Ocean twin 454 crusaders, motors were out of boat when I got it, I’m told the starboard motor is counter clockwise and port is well standard, BUT Starboard motor has the dist. Rotating clockwise just as standard, just the cam is diff. My problem is all the diagrams I’ve seen have the dist. Rotating counter clockwise in the starboard motor
 
Both a STD LH Rotation Engine and a REV RH Rotation Engine rotate the distributor and oil pump in the standard direction.
This is due to the REV RH engine’s camshaft “drive” gear and distributor “driven” gear correcting the rotation. (opposite gear cuts)

In other words...... both ignition distributors will rotate CW when viewed from above!


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Yes that's what I thought, just confusing when I look at other motors, now the ques, is the starboard motor the reverse rotation
 
Yeah if you look at some of the diagrams it shows starboard motor dist. turning the other way, but yes obviously the oil pump must rotate to lube the motor, right now the starboard is in ad I reversed rotation,
 
We can better help you if you tell us which transmissions you have.

Some transmissions are “opposite of engine rotation” capable, which means that two STD LH engines can be used, yet you’ll have counter rotating propellers.

Flywheel forward V drives pose another interesting scenario.

let us know!!!!!


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I have twin 270 (1987) Crusaders, with BW 72's I believe (straight shaft). My port motor is the CCW and the Starboard CW. On the tail end of my Port transmission I have a yellow sticker that says "rotation" with an arrow to the left.

Good luck
Duke1
 
The easiest way is to look at the serial number plate - it should have LH or RH clearly stamped into it with the numbers.....

And getting the gears' model numbers will be helpful as well...a boat that large is likely to have a have a larger reduction than most....if they are B-W gears, you'll want to find the 10-xxx number....
 
I'm certainly not an expert, but have used the vast help of the members on this forum a great deal. My Crusader 454's are configured as ....port side standard rotation, starboard side counter rotation...both distributors turn clockwise.
 
Just went through all this. The BW 72 trans. didn't have a R or L stamped into the id plate. The way to tell was to look into the front of the transmission (off the engine) and see which way the pump was set. The transmissions only need to have the pump rotated to become opposite rotation. Found that in the manual.
 
Sorry if I replied to the wrong question. I thought there was a question as to which way the trannys were working.
Regarding the engines, as far as I have been able to ascertain, all Chevys that rotate reverse have the cam running in the normal direction. Some Mopars and maybe others have a reverse cam/oil pump, etc.
 
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srfdude said:
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Regarding the engines, as far as I have been able to ascertain, all Chevys that rotate reverse have the cam running in the normal direction.
FYI...... in order for a REV RH Rotation engine to rotate the camshaft in the Std LH Rotation direction, it would need to be twin gear driven (one gear on crankshaft and one gear on the camshaft, and in a 2:1 ratio) in lieu of a chain/sprocket scenario.

This is a BBC twin gear driven REV RH rotation camshaft.
Note that the hypoid gear cut is the same as with a standard rotation chain/sprocket driven camshaft (second image).

BBC reverse rotation cam gear driven.jpg


SBC camshaft chain driven.jpg

Many REV RH SBC engine camshafts are chain and sprocket driven, of which allows the camshaft to rotate in the same direction as the crankshaft.
With this style camshaft, the distributor's hypoid "drive" gear is cut in a reverse fashion (as well as the "driven" gear on the distributor shaft), allowing the distributor and oil pump to rotate in the Std direction.


Some Mopars and maybe others have a reverse cam/oil pump, etc.
I am not aware of any REV RH Marine engine that would use a reverse direction oil pump. If one exists, it would be interesting to see it.
Click to expand...







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srfdude said:
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Regarding the engines, as far as I have been able to ascertain, all Chevys that rotate reverse have the cam running in the normal direction.
Click to expand...

Accurate, at least for the Standard Production factory (GM) engines made in the last fourty years.....
and they use the gear drive scheme....
 
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