Mercury stator test procedure

[pete steverson]

[h=2]Mercury stator testing procedure[/h] I have found a lot of useful information on here but unfortunately I am having trouble pinpointing the procedure for stator testing on my exact year.

1989 Mercury 150 Black Max
OC150410
stator 398-9610A3
2-yellow wires
1-blue
1-blue/white
1-red
1-red/white
1-black.
​​​
this is what I have done, it may be incorrect, I don't like the readings I'm getting.

digital multimeter lead to blue wire and black wire 3.91 ohms at the 20K setting on 2K setting 1.

dm leads to blue/white and black wires
3.91 ohms

dm leads to red and black
.110 ohms 2K setting

dm leads red/white and black
.110 ohms

dm leads to yellow to yellow
.5 ohms

from what I gather you don't test this year stator red to red blue to blue Etc? Any help from you guys would be considered valuable! I ordered a DVM adapter for my digital multimeter but it's not here yet I don't have voltage readings available. The visual check on the stator is not too bad however there is some slight pitting and one slight area of green corrosion on a wire connection wondering how big a red flag that is? I have the red flywheel and the magnets look good. I believe this is a 40 amp stator. This year mercury has the voltage regulator/rectifier combined I'm pretty sure that's bad as well my tach isn't working. Thinking about doing both switch boxes and everything all at once. Ouch! Thanks in advance for any advice

 

[pete steverson]

Forgot to mention the stator is off of the motor. I am bench testing it. The procedure I used was in the manual for my year. It said blue to ground, blue white to ground Etc I assumed ground was the black wire. I could not get a reading when trying to use the body of the stator as a ground.

 

[Dukedog]

if your considering changing tha reg/rec and tha stator out also you need ta replace with tha newer stuff. yours is a single, water cooled reg/rec. its not a good system.. think cdi has a "kit" per-say to replace it and stator to tha newer (better and lower priced) (2) dry, reg/rectifiers and stator............. jmo.

 

[pete steverson]

Ok thanks. I am looking at cdi replacement parts. To do the stator, voltage regulator / rectifier, and both switch boxes is over $1,000. I will look to see if they offer a whole kit. So even if my old stator is still good should I not run it with the new CDI switch boxes and voltage regulator / rectifier?

 

[pete steverson]

Good advice on looking for a CDI kit. I called them and they referred me to Kit number 174 - 9610A18. That kit converts the original 1989 Mercury 150 one voltage regulator/rectifier water cooled system into the updated two regulator/rectifier system. It includes the new four wire stator "meaning four yellow wires" the two new regulator/rectifiers, as well as the mounting plate, gasket, and hardware. I did not see it at iboats but I found it for about $650 on eBay which saves you about a hundred bucks if you were to buy it all separate. My original two yellow wire stator cannot be used with the new CDI regulator's so I had to switch it out anyway. I hope maybe this helps someone else considering switching over to the newer system. As far as the two switch boxes go, they ride piggyback bolted to the block. The one on the inside had a burnt smell but didn't look too bad? Either way I'm replacing both of them with the new stator and regulator/rectifiers.

 

[Mbboater]

Hi there. I have the same motor and problem. Thanks for the post. Just wondering how your CDI regulator kit held up? My OEM Reg is fried, and considering a new mercury OEM part # 18736A8 or the CDI kit you did. How much work is it to change the stator. I’ve never done that before. I figured that if the OEM regulator/rectifier lasted 30 years it can’t be to bad to replace it with the same? What would you do next time?

 

[Mbboater]

I also have an intermittent Oil injection alarm that has started to come on at sporadic times. Oil is still being used and the reserve oil container on motor is staying full. It often comes on while pulling tube riders but rairly while pulling wakeboarding. Not sure if it is to do with boat hitting waves? Anyone think that it could be a voltage issue, as the reg/rectifier is not working and battery not charging/no tac. Battery is charged fully prior to going boating so it is only used to start motor. When I get home from boating when alarm turns on, I start motor with water muffs and alarm is off again, making it hard to get diagnosed at a mechanic shop. Any ideas?