1998 mercury 200 carbed no power under load. Need help.

[98Mercury]

Forgive me if I am posting this in the wrong spot. I am new to this forum.

my 1998 mercury 200 carbed ran great for about 6 hours this weekend. Towards the end of the day the motor would not rev to past 1500-2000 rpm while under load / in gear. I believe it's a stator / switch box issue but I'm not sure how to properly diagnose and pinpoint the issue. Engine serial number 0g595896*

Motor idles fine. Revs in nuetral fine. Engine running voltage is 14-14.6 volts.* Ruling out bad gas because motor ran grear under load for first few miles / hours of day.*

I have some ohm readings between some of the wires coming off the stator.*
brown wire yellow sleeve to purple wire black sleeve*
purple wire yellow sleeve to white wire black sleeve*
white wire yellow sleeve to brown wire black sleeve
all read 1167-1169 ohms within the trigger ohms spec according to my SELOC manual.

I additionally individually ohm tested the blue and blue /white wires from stator to ground. Both were open.
the red and red/white wires from stator to ground were 100 ohms. Not sure what this means?

Visual inspection of stator looks like I have one burnt up coil but i notcied that last season and boat did not have any problems running. This outboard is not new to me I have run it 30-40 hours without an issue


Any insights or additional testing would be great. This is my first outboard.

I have been an automotive and light duty diesel Mechanic for 10 years so I have some experience in R&R. Just not sure where to start on an outboard.

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[rock]

Welcome to Scream and Fly. I think you are on point with the stator. Ohm tests are mostly useless on these. You need a DVA to read output.

Rock

[98Mercury]

Welcome to Scream and Fly. I think you are on point with the stator. Ohm tests are mostly useless on these. You need a DVA to read output.

Rock

I have a CDI stator on order. Is there no way to test my current Stator without a DVA?

Should I be checking spark with an inline spark tester?

[rock]

Not that I know of. I have a tool with 8 wires and a ground with an adjustable gap.

Rock

[Jim Speros]

I have a CDI stator on order. Is there no way to test my current Stator without a DVA?

Should I be checking spark with an inline spark tester?

One Saturday morning and a failed DVA later I started tested the stator leads with my fingers. The 2 to 9 volt lead feels like a 9 volt battery when you test it on your tongue. The other one will shock you good but doesn't really hurt. Quick and easy way to find a dead circuit. I got 3 or 4 bad DVA meters and never bought another one.

I too have a 8 cylinder spark tester. Very helpful while troubleshooting. You can compare spark color and notice patterns of lost or intermittent spark.

[Mrzip]

When i pull a Flywheel. Change them both..

[Revenge22]

ive never had a bad DVA adapter. Actually, last year bought a $20 one on ebay for shi*s n' giggles. dead accurate as my stevens and ES ones. If you have a true RMS meter, you should be able to add 30% to the PEAK voltage # it gives you and that should be accurate enough. Meter needs a "MAX HOLD" feature though to capture the highest reading. otherwise you will feel like an idiot trying to catch the highest #, and its always wrong

[OnPad]

Pretty high voltage coming out of the stator to be checking with your tongue. More of a man than me!!!

Made in usa, little white dva, $25 ebay.

[OnPad]

[Jim Speros]

Pretty high voltage coming out of the stator to be checking with your tongue. More of a man than me!!!

Made in usa, little white dva, $25 ebay.

I check with my finger. I compared it to checking a 9 volt battery with my tongue. I also make sure I'm not standing in water and other hand is behind my back not touching the engine.

[Jim Speros]

I guess my DVA meters did not like checking running engines.

[OnPad]

Scared of the lightning, but if Jim sez, I'll give it a shot sometime......., if my dva burns up.

[Jim Speros]

I don't like get shocked either. When your self employed and you want the job out the door to get paid sometimes you go the extra. More often then not I've narrowed it down and a No shock test is confirmation.

[98Mercury]

Ok folks update:

No spark on port side of motor.
I replaced the stator and both switch boxes. All cylinders sparking. Took it to the dock to water test .

Motor ran great and now the problem I am experiencing is a constant warning alarm if I am more then half throttle for 45 seconds or so. I put the boat in nuetral and buzzer stopped after few seconds. I slow rolled in back to the dock no problem. Good flow of water from tell tall and water was warm to touch but not boiling I could hold my hand under it. I touched the cowl and it was also cool to the touch.

I took it home and put in back on the muffs and idled it (1500 rpm for 10 minutes or so) to see if i would get the alaem again. No alarm.
The oil injection system is deleted on this merc. The solid blue wire from the reservoir cap is disconnected at ECM. Black wire from cap still looks like it's grounded to power head. I didn't delete this merc so not sure if previous owner missed something for the delete. I have noticed that the oil res on the motor has always been full but now noticed it's been leaking a little a the fluid level is lower. Is there any good tests for the temperature sensor? I have one sensor in port head with a brown wire and black to ground. And one sensor in starboard head with a brown wire / blue tracer looks like goes to an assembly next to starter solenoid on starboard side.

Are the only two things can cause a constant alarm is over heat condition or low oil tank res?

[OnPad]

Only solid tone is overheat. Oil injection is a broken, not solid tone. Maybe sensor?