Can someone explain what this plate is?
Doesn't look marine- (beside the fact I've never seen a four speed boat) marine engines had a somewhat different manifold with the carb flange cut at a pretty severe angle, cast oil pans (iron or aluminum depending on the year), a cast iron timing cover, and the early style iron water pump right up through the end of production in the mid 80s. Not to mention the marine exhaust manifolds.
Pic of manifold:
Reverse engines are easy to spot- in addition to what was already mentioned, they had a thick bearing plate under the distributor (to keep the intermediate shaft from pounding the distributor due to the reverse rotation) and to allow fitment of a B engine distributor to allow the advance mech. to work in RR, and a strange looking oil pump- again, due to the rev. rotation.
The OP's motor plate actually looks like a manufactured piece hijacked from a stationary industrial motor application, saw a similar looking setup years ago on an irrigation pump. I'd pay close attention to the timing cover, it may have been thinner than standard in order to keep everything lined up- water and fuel pumps, pulleys and alternator; not to mention allowing the balancer to seat all the way on.
Doesn't look marine- (beside the fact I've never seen a four speed boat) marine engines had a somewhat different manifold with the carb flange cut at a pretty severe angle, cast oil pans (iron or aluminum depending on the year), a cast iron timing cover, and the early style iron water pump right up through the end of production in the mid 80s. Not to mention the marine exhaust manifolds.
Pic of manifold:
Reverse engines are easy to spot- in addition to what was already mentioned, they had a thick bearing plate under the distributor (to keep the intermediate shaft from pounding the distributor due to the reverse rotation) and to allow fitment of a B engine distributor to allow the advance mech. to work in RR, and a strange looking oil pump- again, due to the rev. rotation.
The OP's motor plate actually looks like a manufactured piece hijacked from a stationary industrial motor application, saw a similar looking setup years ago on an irrigation pump. I'd pay close attention to the timing cover, it may have been thinner than standard in order to keep everything lined up- water and fuel pumps, pulleys and alternator; not to mention allowing the balancer to seat all the way on.