4.3GL octane requirement and does it have knock sensor?

USA_boater

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I always assume marine engines require 91 octane gasoline but if this motor can run on lower I'd be interested.

Also, not sure which version I have (I think C or D) but no luck so far finding out under the hood...an '04 made in '03 would be a C or D? Thanks!
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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87 octane if using the US R+M/2 method. 91 or higher for the RON method

use your serial number of the motor. the C or D is simply the year of that particular run of that particular model number.
 

USA_boater

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Well most of the pumps around here seem to say R+M/2 and then the inspections usually show +1 or +2 octane points so the 87 octane here is 88 or 89 if I am to believe the pump sticker. I just always though marine engines used more timing advance and compression and therefore needed super unleaded...if not that will be nice...save some bucks...perhaps I'll go with 89 octane (which is also testing +1) just to be safe...
 

Scott Danforth

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read your motor's operation manual

marine engines have less timing and less compression than car motors. think more like a dump truck motor.
 

USA_boater

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Okay thanks again for all the help...do you know if this 4.3GL has a knock sensor?

Also, I checked out your build thread...very nice boat! The interior reminds me of the '86 Chris Craft cuddy cabin boat a family member of mine used to have back in the 80's/90's..only time I ever para-sailed was behind that boat.
 
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