Re: early 80's bubbleback 140
The early 140 crossflows were a sought-after engine. They had some nice tricks that the other engines did not have. High compression heads, large carbs, bubble back exhaust and intake filler blocks. OMC made these V4 engines by the tens of thousands back then and parts for them are still readily available. The 140 looper replacement engine in 1985 is a much heavier engine than the crossflow, with larger displacement. When that looper 140 engine debuted, OMC changed the crossflow: dropped the intake filler blocks and re-rated them at 115. The 85 115 still used a high compression head, and the bubble back exhaust, so the performance difference compared to an older 140 may not be all that apparrent. All crossflows can accumulate carbon around the piston rings with age, so an occasional decarb will keep the engine running healthy.
