Sample of Engine ID's
The AQ, BB, and MB red gas engines were built until 1989, and were named based on the horsepower or displacement of the engine.
Examples:
1.) The name started with:
AQ = sterndrive engine
BB = inboard
MB = inboard
2.) Next came the number for the displacement or horsepower.
3.) Most of these also included a one letter suffix, for version control.
An AQ271A is older (and different) than a AQ2718.
Nothing in the name relates in any way to years of production. Some of these engines were in production for less than a year, others for many years.
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