Stator question for Rodbolt

3rdday

Cadet
Joined
Sep 4, 2007
Messages
10
RodBolt,
I have read older threads re ox 66 2.7l, where you have stated; when an entire bank (starboard) of cylinders is losing spark that it is most likely (99% of the time)the stator.
I believe this is the problem with my 1999 200HP 0x66 EFI (sx200txrx).
At higher rpm, most of the time does not exhibit the problem, but after trolling rmp 1500 or so it will exhibit intermittent , or weak spark on the 1,3,&5 cylinders. It will also exhibit the problem at lower rpm after backing down from trolling RPM to Idle RPM.

I am confident it is the Stator ,mostly becuase I am confident in you, after reading your many posts and answers. I do have some questions and confirmations, please;

Should this motor continue to run if I disconnect the Positive cable from the battery? Wh at shoudl I expect to happen on this engine if it were running perfect?

I believe it is still charging the battery(tested battery), however the motor dies within 20-30 seconds of disconnecting the positibe battery terminal.

Also does this engine have the CCS? where it runs less than 6 cyl below 1800 RPM? I ask becuase at Idle the spark is weaker on some cyl than others. If so which coils do not fire or produce weak fire?

I also checked spark strenght with a tester at 1800 RPM it will jump at least 1&1/4 inches with a tenacious snap on the Port Bank, on the Starboard bank at the same RPM it will jump about 3/4 to 1" on the starboard bank and the snap is not as loud.

I have asked questions and provided information as to avoid a volley of back and forth and to TRY to avoid further questions, but would like to be sure before droping the significant coin on the Stator Coil.
Much Thanks in advance!
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Stator question for Rodbolt

ok spark only has to jump a 7/16ths gap. DO NOT remove a battery lead as on that engine its a usless test at best and can smoke electrical components at worst.
your motor does not use CCS.
test stator output when warm with a peak reading multi-meter.
 

3rdday

Cadet
Joined
Sep 4, 2007
Messages
10
Re: Stator question for Rodbolt

Thanks for the advice and the warning about the battery, It makes sense, as I have heard that loose or bad battery connections, or rotating a selector switch while running can kill the stator or cause surges or spikes.

I will test stator with DVA, warm, as you recommend and report back.

A genuine thank you again.
 

3rdday

Cadet
Joined
Sep 4, 2007
Messages
10
Re: Stator question for Rodbolt

Rodbolt,
Ok finally got the DVA adaptor & the time to test.
Per the shop manual, battery fully charged.
Test 1; Engine Cold. I checked the Voltage of the lead coming off the stator Disconnected- In Test 1 & 2
Suposed to be 85-100V while cranking and 150V at 1500-3000RPM
red & brown gave me 40V at cranking- way below spec
Black/w red and Blue at cranking gave me 148V- way above spec

Test 2; Engine Warm. Red & brown gave me 68V at cranking- way below spec
Black/w red and Blue at cranking gave me 144V- way above spec

Test 3; Engine Warm. Stator Lead Connected to CDI.
At 1500 RPM red & brown gave me 90>110V Suppoese to be 150V
Black/w red & blue gave me 16V

This is really bizarre, the pair that was giving the higher voltage during cranking is now giving much lower voltage during running.???

Probably a bad stator?
Just curious, why the overvoltage on the Black Red/Blue pair at cranking and super low Voltage at 1500 RPM?
Which pair off the Stator feed the starboard bank?
Much Thanks in advance.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Stator question for Rodbolt

beats me but on the stator question its irrelavent as you cannot access any of the coils.
all one piece.
 

3rdday

Cadet
Joined
Sep 4, 2007
Messages
10
Re: Stator question for Rodbolt

I Know it seems obvious, but anyway, Is the stator bad?
Thank you for your help.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Stator question for Rodbolt

could be one of two things, either the CDI is loading the stator or the stator failed.
looking at your unloaded numbers leads me towards a stator failure.
voltage specs are minimums and usually above spec voltages are acceptable.
but double check the crank position sensor.
if the capacitors in the CDI charge but cannot discharge voltage will be way low.
you can see it with an analog meter, the needle will swing way high then fall back as the caps charge but cannot discharge. digital meters wont catch this.

also check the CDI output.
 
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