Matt Butzer
New member
I've got a 1969 Merc 20 hp and the SELOC manual. It explains the Full Throttle Advance setting (.275 BTDC) fairly elaborately and I've got a good handle on setting that, but it also references the Maximum Spark Advance (.375) in the appendix, and I'm not sure what they are talking about. I'm doing a complete overhaul (more or less) on the motor and would like to check as many aspects as I can so if someone could explain how to check and set this that would be great. Thanks for the help and the time.