Should be set by dwell 28-32 degrees approx. .017
The correct maker point gap setting on the 1972 model, 20 hp Mercury outboard is .020in.
30 degrees dwell
.017 The dwell on a 1972 225 ci slant six is 41-46 degrees, the point gap between .017 and .023. So .020 would be your best place to start.
.019
BAD IGN SWITCH
.o17 to .019
.035" is factory using standard point type ignition.
the dwell is 29 to 31 degrees and the gap is .019.
4, to 6 degrees advanced, (BTDC) initial, or 30, to 32 degrees total.
No.
I believe 1967 for Chevy cars and 1972 for Chevy trucks.
Use a dwell meter to adjust the points to 30 degrees dwell.