Reply To: 1970 4 HP, one cyl American Made Mercury

[David Stanton]

The part number is close ,but not quite the same on the brown and green coils. Note that in the manual pages you posted, Crosbyman, it gives slightly different resistance readings for “Green” , and “Brown”, while red and brown coils are the same readings. These values are all in the same testing info tables, so there is a difference. The green has slightly higher resistance readings for the primary, and 5 to 6 times the resistance in the secondary. I’m thinking a lot more secondary turns will step the spark voltage up higher, but I don’t want to risk an artifact getting back on the primary and killing the stator. The green one was probably made for a different pulse voltage from the capacitor.

I’ll check my other parts motors for a brown one, and if I can’t find one, I’ll probably try the green coil.. This motor is not worth $180 for a new coil. No aftermarket ones show up.

As long as I’m on here again, I’ll “FYI-mention” that the capacitor must be potted up in the stator, as it’s not there and does not show on the parts list or exploded view.

Some day , maybe I’ll learn to tell people “no” when they have a Mercury to work on – they take way more of my time than OMCs and Champions.
Dave