Yanmar 3TNV Series Service Manual page 165

9. Starting Motor
(4) Brush holder
(a) Brush holder insulation test
Check the continuity between the brush holder (+ side)
and base (- side) with a multimeter. Good if no
continuity exists.
If continuity exists (insulation defect), replace the
brush holder.
(b) Brush spring inspection
Inspect the brush spring pressure.
N(kgf)
Standard spring force
31 39 (3.1 3.9)
(5) Magnetic switch
When the starting motor is wetted with water, always
replace the magnetic switch with a new even if the
function is normal.
(a) Shunt coil continuity test
Check the continuity between the S terminal and the
switch body. Good if continuity exists.
If no continuity (coil disconnection), replace the
magnetic switch.
150