Mercury xr2 150 Voltage Regulator / Rectifier Wiring Questions

[kschnebly]

1987 Mercury 150
serial OB119610
CDI Voltage Regulator 194-8825K1
CDI Rectifier 154-6770

I am looking for a wiring diagram that shows the connections on a 1987 Mercury 150 that uses both a voltage regulator and separate rectifier. I am replacing the stator and trigger and decided to pull the rectifier and regulator to bench test thinking that the seloc marine wiring diagram for my model number would help me when it came time to reinstall. No such luck.

 

[merc850]

This worked for me on a 1975 850. Make sure it's bolted to a metal surface.

 

[kschnebly]

I've only owned the boat for 3 years and have had performance issues the entire time. The date on the Regulator and Rectifier is 2009 so they have been on the boat a while. I'm pretty sure with what I have read about the CDI Regulator is that it replaces the OEM regulator AND the Rectifier. However, The diagram attached is how it was wired on my motor with the rectifier still connected.

 

[merc850]

When the motor is running @ 4000rpms you should be getting around 13.5v this is how you check its operation, I don't know anything about the CDI unit the one in the schematic is a Mercury part /old/ Nr. 88825A7 have you looked on the CDI site to identify those components?

 

[Dukedog]

tha drawing 850 put up will work on yours as well.. tha drawing you are showin' in post 1 is for a 9 amp.. no reg required... tha drawin' you show in post 3 is with 20 amp regulator (non oem for your motor) added... it should work... but this is jus my experience over a lota years dealin' with tha v6 merc.. with very good name brand battery type and battery maintenace and you have any kinda current draw with normal operation of tha rig a regulator is not necessarily needed with tha 16 amp.. i get a lotta "oh no's" with this but i've done it for years without any problems at all....... jmo

 

[kschnebly]

Update: I spoke with CDI about the regulator that I have on my motor. I was informed that the CDI aftermarket regulator has both the regulator function and the rectifier function in a single unit. When using that type of regulator, the original independent rectifier and original independent regulator should both be replaced with the CDI regulator/rectifier unit that does double duty. The way the previous owner had my motor wired, the stator was wired to both the rectifier (which should have been removed per CDI) and the CDI regulator/rectifier. The independent rectifiers positive power supply was connected to the CDI regulator/rectifier which was backfeeding the CDI regulator/rectifier. This shorted out the CDI regulator/rectifier and when bench testing it failed on one yellow lead and one red lead. According to CDI, this could have been putting 12vDC back to the stator creating an magnetic field that negatively impacts the stator performance on the ignition side (even though the regulator/rectifier is not intended to have any impact on ignition). At Idle/low rpm the stator sends the correct current to the switch boxes and the coils fire correctly. At higher rpm, the stator sends an irregular current (most commonly a voltage drop) to the switch boxes resulting in poor ignition and low performance. The plan is to replace the stator, trigger, regulator/rectifier and wire everything correctly. This isn't easy to test on muffs so I'll have to see how things go when I drop it in the water. All together I'm in for around $900 in parts including the switch boxes and plug wires I replaced previously.

 

[Lt1z350]

I went through some issues on my 89 with it missing spark on 2 cylinders at idle and cleaned up at 3000 but wasn’t perfect. I did a stator trigger and regulator all cdi parts. Had already done plugs and wires. So at 3k it was really good now but idle not so much. One plug was not burning good so I went to swap the coils around and found oil underneath them all. I cleaned all that up with brake cleaner and took the coils from plastic housings and cleaned that too. Put back together and got a perfect idle and all plugs now look the same on how cylinders are burning. I knew I had 130 psi on every cylinder so not mechanical so it was basically chasing down a random missfire on the same two cylinders. Mine had all factory parts still dated to 89 so replacing it all was my first decision as didn’t want to be stuck on the water st any point even if had got it running well on old parts. I went in really deep on Diag and even did all 3 carbs so if have a specific problem maybe I can help since sounds like I went through what you did or still are. Can message if have a specific question.
Joe