1999 Mercury 150 XR 6 voltage regulators wiring modification

mgoff

Seaman
Joined
Aug 13, 2014
Messages
56
I modified my voltage regulators to get rid of the bullet connectors and installed a 1 amp fuse holder in the sense wire and a 30 amp fuse holder in the voltage feed line after a new C.D.I. voltage regulator burned out when I turned on the battery switch. Special thanks for the info. I got from Sam am I, Dukedog, and GA boater on this forum. Here are the steps I took to correct this problem with pictures. I hope this helps anyone who is considering a similar modification.

Identified and labeled all the wires on the outboard connecting the regulators, With the battery switch turned off and the negative cables removed I unplugged the bullet connectors, removed the ignition coils ground wires from the power head and unbolted the ignition coils plate and pulled it back enough to get access to the regulators. Removed the spacers and voltage regulators and cleaned the heat sink compound off the back of the power head.
modified voltage regulators installed.jpg Cut off the bullet connectors after labeling the feed and sense wires. The sense wire is the red wire female connector. Soldered in a 1 amp fuse holder in the sense wire and a 30 amp in the feed voltage red wire and heat shrink wrapped them. Cut off yellow stator wires bullet connectors and gray tachometer connector from #1 upper regulator and soldered/ heat shrink wrapped, and color code taped the wires offsetting soldered connections so they would not be stacked on each other.voltage regs sense & feed wire fuse soldering.jpgvoltage regs sense & feed wires  fused.jpg
Applied Duralast heat sink compound pn# SL203, 2 to a box, to the backs of the voltage regulators and slid them on the mounting bolts, installed the spacers and ignition coil plate and torqued to specs. Refastened ground wires from ignition plate to the power head and completed installation. voltage regulators heat shrinked & color coded tape wrap completed.jpg
Installed the fuses in the holders making sure the seal on the 30 amp holders were in the upper position so that when Feed wire fuse seal position prior to snapping together.jpg snapping the covers on them they would properly seal.
 

Attachments

  • voltage reg 2 to stator wiring soldering.jpg
    voltage reg 2 to stator wiring soldering.jpg
    1,003.4 KB · Views: 5
Top