Merc Gurus...I need some help....Final update....

Laddies

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Sep 10, 2004
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12,218
Re: Merc Gurus...I need some help....Final update....

Kenny, first I don't know why I am even posting, it sounds to me like rodbolts hit it right on the head mercury built stators have a interior bond wire on the inside of the stator when it comes apart for what ever reason it comes and goes and will send a guy to the bar. You need to ck high speed output with a load on the engine, DVA or an Induction tach, some cases you can run the engine up slowly and when it starts to miss back it off, if it smooths out you try it a couple of more times to make sure it repeats it's self and if it does you can be sure it's the stator---Bob
 

rodbolt

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Sep 1, 2003
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Re: Merc Gurus...I need some help....Final update....

thats the whole reason why I use an analog peak reading meter. the digital is ok but not for this. the analog needle will pick up momentary shutdowns on the coil primary side due to any shorts in the kill circuit or a failing pack or a bad stator. then you can go up or downstream as needed. also why I have 3 of the meters:) 2 CD-77 and the merc one as well as a DVM with a DVA attachent. it enables me to look at more than one thing at a time. but all tests have to be done under a load. a failing ign coil will not usually show up with a peak reading voltmeter unless its shorted to ground. the orange, yellow, and blue coils have been known to crack and arc to the center magnent. A Kv tester will catch that one. a Kv tester will also catch a fouled or open plug as well.
 

walleyehed

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Jun 29, 2003
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Re: Merc Gurus...I need some help....Final update....

OK Boys...I've got some issues I can't deal with here...#1 found my stupid seloc doesn't cover the ignition system I have...<br />I have tested the stator out-put and all I get is 75-100 volts...My coils (3) all have 2 terminals and 1 high-tension lead. each coil has a green wire going to one terminal and the other terminal is ground. I have a red and a blue going to switch box. with red disconnected, I show 160 ohms resistance between red and ground.<br />Voltage output at coil is the same as stator.<br />For grins I checked the DC output at the rear(2 yellow, 1 red)reg/rect.??? dc voltage is 16.8-19.5 volts at Idle with batt fully charged with maintainer. as a matter of fact, it lights up the starter battery light on the charger without being plugged in!!!<br />I ran with the test prop and was testing each sparkplug lead and lost the bottom fire, and I thought I found the trouble because it wouldn't fire the gap of tester, but did the other day..??? Checked resistance of all 3 plug wires and they were all very, very close. Inspected for bad spot, crack, something...nothing found.<br />Put wires back on and engine ran fine...jumped gap on tester, all 3 leads, and no hesitation from 1500 to 4500 which was as fast as I could run with the cut prop without blowing all the water out.<br />I gotta get a new manual...<br />Does this throw any red flags for you merc guys???? I know the charge voltage (DC) is high, but other than that, my AC voltage figures aren't anywhere NEAR where I believe they should be, and the stator is sticking in my mind as the culprit.
 

rodbolt

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Sep 1, 2003
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Re: Merc Gurus...I need some help....Final update....

75 to 100 V on the coil primaries is becoming borderline. it will quit compleatly about 60-65 V.<br /> usually a stator will affect all three coils. a trigger can affect just one, a switch box can affect just one and a internal coil crack can affect just one. but at 75 V peak its getting a bit weak. test between the blue and red leads, should see about 5400-6200 ohms.
 

walleyehed

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6,767
Re: Merc Gurus...I need some help....Final update....

Resistance between red and blue, unhooked, is 2400 ohms.....
 

rodbolt

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Sep 1, 2003
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Re: Merc Gurus...I need some help....Final update....

according to my manual 90-86135--5 that covers 3 cyl 70 with seriel 4571652-6428681 USA, it should read a lot higher. however I cant find any peak reading specs. I can look at another manual with similar stator and trigger resistance values and try. mostly I try to take readings from everything and compare them when no known specs are avalible.
 

walleyehed

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Jun 29, 2003
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Re: Merc Gurus...I need some help....Final update....

Ordered a new stator and reg/rect., we'll see what happens Monday....<br />Thanks for the assistance.
 

walleyehed

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Jun 29, 2003
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6,767
Re: Merc Gurus...I need some help....Final update....

Hey Rodbolt...new stator fixed everything!!<br />Voltage figures are now correct as are resistance values. I think this has been an issue that has gotten worse over time because it runs better than I ever remember, now.....<br />Thanks for the help....it led me to find the problem..<br />Kenny<br />p.s. I replaced the Reg/rect. and voltage is back where it should be on the DC side as well.
 

LubeDude

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Oct 8, 2003
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Re: Merc Gurus...I need some help....Final update....

I love stories with a happy ending, I think Im gonna cr............oh never mind.<br /><br />Glad ya got it figured out. :cool:
 
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