Mark V
Member
2006 Mercruiser 350 MAG MPI/Bravo III.
800 hours on it, including original starter.
This only pertains to cranking an engine that won't start:
Has anyone ever watched the max RPM achieved when cranking their engine, when it has a problem and won't start? What did RPM you get?
On a related note, has anyone ever heard of a minimum RPM needed to start the engine?
I confirmed mine is only reaching 120 to 150 RPM with all the spark plugs in it and no sputter or signs of starting. (tach at the helm agrees with a calculated RPM I got counting rotor turns for known number of seconds and doing the math)
With all the spark plugs out and a compression gauge on one cylinder at a time, it peaks and holds at 180 to 190 RPM.
Mercruiser Tech Support indicates there is no specification for minimum RPM required to start the engine, nor could they provide a "typical" value.
Various internet boating forums mention RPM values "required" between 250 and 350 RPM needed to fire it up.
800 hours on it, including original starter.
This only pertains to cranking an engine that won't start:
Has anyone ever watched the max RPM achieved when cranking their engine, when it has a problem and won't start? What did RPM you get?
On a related note, has anyone ever heard of a minimum RPM needed to start the engine?
I confirmed mine is only reaching 120 to 150 RPM with all the spark plugs in it and no sputter or signs of starting. (tach at the helm agrees with a calculated RPM I got counting rotor turns for known number of seconds and doing the math)
With all the spark plugs out and a compression gauge on one cylinder at a time, it peaks and holds at 180 to 190 RPM.
Mercruiser Tech Support indicates there is no specification for minimum RPM required to start the engine, nor could they provide a "typical" value.
Various internet boating forums mention RPM values "required" between 250 and 350 RPM needed to fire it up.