PDA

View Full Version : Mercury Tech 1984 115hp Inline Switch Box wiring



MNhunter1
07-21-2025, 12:17 PM
544056544057

Upper switch box grounding wire – top coil pack has ground wires running to top left screw of the upper switch box. There was also another ground wire running from this screw to the Neg post on the starter.
Is there a correct way to ground the upper switch box? Any harm in the how it was set up to ground off the starter?

544053544054544055


Stator wires – Mercury manual shows red/white strip and blue/white strip going to top switch box with solid red and solid blue going to lower switch box. Manual also states yellow sleeve wires should all go to lower switch box. However, the stator wiring for my motor has the red/white stripe and blue/white stripe stator wires in the yellow sleeve. So…do I go against the manual color codes and connect them to the lower switch box, or ignore the yellow sleeve and connect them to the upper switch box?

rhardwick
07-22-2025, 12:06 PM
Nothing wrong in grounding it to the starter. Originally the switch box is grounded through the case internally, grounded to the mounting plate with the 4 mounting bolts.

On a side note I would check the red lead from the rectifier to the solenoid + battery cable, looks like it may have burned or just wrapped with tape.

MNhunter1
07-22-2025, 01:31 PM
So, the switch boxes are inherently grounded with the mounting bolts? No need for a separate ground wire?

skialot2
07-22-2025, 01:45 PM
What brand stator? I would ignore the yellow band. It's more likely someone put the band on the wrong wires then someone wired the stator backwards. Although, I had a cheap switch box that was assembled backwards. The green wires all had to be connected to the posts labeled for violet, white and brown

MNhunter1
07-22-2025, 01:56 PM
Not sure on the brand, it was installed by the PO. Will I fry anything if I try to start it with the wires incorrectly wired? Is there a way to verify they are correct/incorrect? Just rebuilt carbs and fuel pump. Getting everything put back together to hook back up to battery and trim up for the impeller change and lower unit oil change. From there, plan to double check TDC, set timing, and try to turn her over for the first time in 5+ years.

skialot2
07-22-2025, 02:22 PM
Are you sure it works to begin with? I cant say for sure, but I don't think it will hurt anything if the wires are wrong. The wires are still connected to the right place just the wrong box. That backwards switch box worked after I wired it correctly(backwards) It might make the upper box act like the lower and spark at the wrong time.

MNhunter1
07-22-2025, 02:28 PM
It’s got compression on all 6, and I have 3 other towers here to steal parts from if needed, so she’ll talk…eventually :D