Crusader to Mercruiser

[amerosport]

Would anyone know what changes must be made to reverse the rotation of a 454 engine? I have purchased 2 1992 454 Merc engines with the same rotation to replace my 1987 454 crusaders one clockwise rotation and one counter clockwise.

[tuantom]

The camshaft, distributor gear to match, and the front and rear seals, as they are rotation oriented. I'm not sure about the water pump - it is probably bi-directional though. Does the cooling system change with rotation?
I would take the existing cam to a cam grinder and have them grind one to the same specs, only reverse. I know someone who had this done using Delta Cam in Tacoma, Wa and are happy with the results - though there are plenty of grinders capable of this. I used them for a standard rotation cam/lifter kit for a small block Ford - total was $135 with shipping.
When I was rebuilding my boat's engine, I learned stock replacement does not necessarily mean identical to stock; and you'd probably be better off if both engines had the same performance characteristics.

[kenJ]

Wouldn't it smarter to change the rotation direction in a gearbox rather than the engine?

[amerosport]

It would be nice but they are Borg Warner V drives.I believe changing the engine rotation would be easier. I was wondering what components need to be changed. Thanks

[pila]

A few years ago I had a cams ground by Competition Cams. They seemed to know the specs of various marine cams. One was for a reverse-rotation Chrysler 360. Both engines seemed to behave the same, so I guess they knew what they were doing. That was a flat-tappet cam. The other was for a normal rotation 5.7 Mercruiser (chev), also a flat tappet type.
The 1992 454s are roller cammed I would think. You may want to remove the intake manifold to verify that before getting a new cam. The rollers seem to last a very long time, so you could likely re-use them on a new cam. It's not like a flat tappet type, where the lifter mates to a lobe.