Stator Failure - Symptoms?

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tntwalker

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Hello all... I've done a good bit of searching and reading many many messages regarding Stators and their function. I'd like to know what symptoms one would experience if their Stator is going bad? and what is the true purpose of the Stator? What does it do?<br /><br />I've recently put my boat/motor in the shop to determine the cause of a rough idling situation... They tested most of the systems on the motor and have determined the stator needs to be replaced. Is it possible that a failing stator could cause a rough idle?<br /><br />If indeed the stator needs to be replaced, what does a new stator for a 1989 Evinrude V6 150 go for? <br /><br />Thanks to all! I thoroughly enjoy reading these forums...
 

Joe Reeves

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Re: Stator Failure - Symptoms?

TNT.... The stator is a dual purpose component. Small coils arranged on the sides of the stator are for battery charging purposes. The larger coils supply approximately 300 AC volts to the powerpack(s).<br /><br />A failing stator, when it first starts to fail (melt down) will usually generate the proper voltage to power the powerpack(s) when cold. But as it heats up, a voltage drop will occur that causes erratic ignition.<br /><br />If your engine idles okay when cold but not when it warms up, the cause could be a stator problem. If, on the other hand, it does not idle under any circumstances but will hit full throttle etc, I would suspect a carburetion problem.<br /><br />This is not to say that your stator is not faulty as you may have two problems (it happens). Inspect it to see if a melt down is taking place. If so, a sticky substance will actually be dripping down out of it to the block.<br /><br />The 35 amp stators run extrememly hot. This eventually causes a melt down of the larger coils, which in turn causes a voltage drop to the powerpack(s) resulting in erratic or no ignition (spark).<br /><br />Reverse polarity to the rectifier (converts AC to DC) will cause the rectifier to short out. This leaves the stator being unable to charge the battery, resulting in a back up of power causing and adding excessive heat to an already hot running item.<br /><br />Note... a tachometer operates off of the charging system. If the tach operates, the rectifier is okay.<br /><br />The 1989 150hp OMC outboard engine can be equipped with either a low amp stator or the hot running 35 amp stator. Hint... if the flywheel has cooling holes near the outer rim, it's a 35 amp system.<br /><br />The stator price depends on which ampere model you have but it will be two or three hundred dollars, possibly slightly more.
 

tntwalker

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Re: Stator Failure - Symptoms?

Thanks Joe... I appreciate the input... It does have trouble idling at any temp... I have a good tach read... so rectifier is okay... I will contact the shop and make sure they've tested that component just for good measure... I'll also ask to see the old stator to look for the signs you have mentioned. I will report on the performance of the motor once work has been completed... If indeed it continues to idle poorly, I will have the carbs rebuilt... I would try this myself, however I have none of the specialized tools necessary to complete that task. Dang thing has 3 carbs so I'm sure it won't be cheap to have someone else do the work.<br /><br />I just can't wait to have it running like it should... It's annoying to have it cutting out at low trolling speed and idle... Makes for dangerous situations sometimes...
 

tntwalker

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Re: Stator Failure - Symptoms?

Good day all... Just wanted to follow up on this problem so maybe it will help those out with similar issues in the future...<br /><br />Replaced the stator with a CDI brand stator... Now the intermittent spark problems are gone except for Cylinder 3 which is completely dead.<br /><br />I've been told the Power Pack is bad. Someone help me here... Can a power pack go bad on just one cylinder? The part is only $135 so it ain't that big of a deal... but would still like to know before slapping one on.<br /><br />One other question... Will it kill my engine to run on 5 cylinders this weekend?<br /><br />Thanks!
 

james roach

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Re: Stator Failure - Symptoms?

In my experience with my 1987 200 HP Johnson, when one of the power packs went bad, all 3 of those cylinders on the port side went out. This created a rough idly and a motor that would not plane off. Your new problem sounds like maybe an ignition coil. Swap the coil out with another cylinder and see if the missing spark moves to the other cylinder also. The biggest lesson I have learned from these V6 OMC's is that heat is a killer for their electrical parts. Good luck and please post results. This is not done enough on this forum.
 

tntwalker

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Re: Stator Failure - Symptoms?

Thanks James... <br /><br />Upon further review... This motor has ONE powerpack that serves all six cylinders... I have good spark to 2-4-6-5... 1 and 3 are intermittent at best... I notice a difference when pulling plug wires on 2-4-6-5, but not with 1 and 3... Redundant enough? The marine shop I took it to said they tested all the coils and all of them were fine. I guess considering the age of the motor, it ain't going to hurt me to invest in the new stator (already installed) and a new power pack. <br /><br />It runs rough on 4 cylinders as expected, but seems to idle on the muffs... I'm sure it won't fair so well on the water, so I think it will remain in the driveway until the powerpack arrives on Monday. <br /><br />For those that are interested, Seiler Marine (www.seilermarine.com) is where I purchased my parts and they had no problem shipping 2nd Day Air at my request. Great people to deal with!<br /><br />I hate to be a parts swapper, but at least it ain't costing me an arm and a leg... (yet)...<br /><br />If this doesn't remedy the situation, I will assume the only part left that could cause a spark problem would be the coils on 1 and 3... I'm hopin my shop is reliable though. Only charged me one hour of labor to test the entire ignition system, replace the stator and retest the system...
 

12Footer

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Re: Stator Failure - Symptoms?

EDITED.. I was going to sugjest you ohm-check the trigger before buying a new cd pack.
 

tntwalker

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Re: Stator Failure - Symptoms?

I've already installed the new stator... Old stator was melted... Crud running down the block... Stator lasted 14 years... Not too bad...<br /><br />Swapped coil between 3 and 5... no change... still no spark on 3... so coil is ruled out... <br /><br />I'll let you know what happens when I replace the powerpack... Hopefully all will be well in the world!!
 

tntwalker

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May 27, 2003
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Re: Stator Failure - Symptoms?

Well new powerpack has been installed... Ignition problems are solved... However I STILL have a rough idle... which leads me to "cleaning the carbs" I would assume. Although all the plugs are wet... <br /><br />Guess I'll jump in head first and learn how to rebuild carbs... Hope my Clymer manual helps me out... <br /><br />What type of special tools are necessary for rebuilding carbs? I know a few are mentioned in the manual, but was just wondering how many shade tree mechanics on this forum rebuild carbs without fancy tools.<br /><br />Thanks!
 

w2much

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Jun 22, 2005
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I would qualify here. Except that there is no shade. For that motor I would think the only special tool would be a good orifice tool or just a good strong narrow screwdriver. A flat surface,perhaps glass to check your bowls for warpage. Maybe use you cell phone camera each step of the way. Just do one at a time in case u get lost. Follow your manual and you will be fine.
 
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