Mercruiser 2bbl Mercarb Jetting and Carburetor Information

The information we provide below is from information we received from service bulletins. It does not provide for all years. When new, all engines are jetted for sea level and it is the dealerships responsibility to re-jet for the altitude the engine is going to be used at. Because of all these variables, we cannot determine which jet's you currently have in your carburetor - this is your responsibility. We provided the below table for comparison's, baseline jetting, and part # information.

Note: the # stamped on each jet indicates the size in mm's. For example - a 150 stamping would correspond to 1.50 mm.

Models	Carb. Part#	<5000ft	5000-9000ft	>9000ft
2.5L / 3.0L	1389-9562A 3310-806077A_ 3310-860070A_	1.45 mm	1.40 mm	1.35 mm
3.0L S/N OF353099 AND BELOW	1389-815396A_ 3310-806078A	1.60 mm	1.50 mm	1.45 mm
3.0LX	1389-815397A_ 3310-805924A_ 3310-807504A_	1.65 mm 1.60 mm 1.55 mm	1.55 mm 1.50 mm 1.55 mm	1.50 mm 1.45 mm 1.45 mm
4.3L, 4.3LX	1389-9565A4 1389-9565A_ 3310-806080A_ 3310-806972A_ 3310-807764A_	1.65 mm 1.60 mm 1.60 mm 1.60 mm 1.60 mm	1.55 mm 1.50 mm 1.50 mm 1.50 mm 1.50 mm	1.50 mm 1.45 mm 1.45 mm 1.45 mm 1.45 mm
5.0L	1389-9563A_ 3310-806081A_ 3310-861080A_ 1389-9670A_ 3310-806082A_	1.70 mm 1.70 mm 1.70 mm 1.85 mm 1.85 mm	1.60 mm 1.60 mm 1.60 mm 1.75 mm 1.75 mm	1.55 mm 1.55 mm 1.55 mm 1.65 mm 1.65 mm
5.7L	3310-807312A_	1.65 mm	1.50 mm	1.45 mm