Points ignition Mercruiser V6 Ballast resistor... I don't get it??

Howard Sterndrive

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Can someone explain Wire 22 to me - I see it provides a full 12V during cranking to bypass the ballast resistor... no problem. I get that.
mr185ign.jpg

Here's the problem.... when I release the key to the run position, the wire 22 is still connected!.... so obviously electricity flows "backwards" on it from the ignition circuit to the starter solenoid. Not enough current to try to start, but enough to suck all the current away.... it is a low resistance path. There is almost no current flowing to the coil.
Should wire 22 have a diode in it?

1983 Mercruiser MR185 V6 Chevrolet
 

Howard Sterndrive

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

oh crap... I'm thinking I hafta move wire 22 off the starter S terminal and over to the R terminal....?

getting the mirror out again :)
 
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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

U got it!;) There's no way of seeing those terminals on the starter in that diagram, not even with a microscope:D
 

Howard Sterndrive

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

and this is the R terminal? correct?
this mini starter has no labeling of terminals
rterm.jpg
 

Don S

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

Wire 22 hooks to termial D in this picture.

attachment.php
 

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stonyloam

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

Can someone explain Wire 22 to me - I see it provides a full 12V during cranking to bypass the ballast resistor... no problem. I get that.

That wire is on a terminal where the contact is is only closed when the starter solenoid is activated. As soon as the key is released the contact opens and brakes the circuit. So if you put a ohmmeter on that terminal (to ground) you should read an open circuit (starter not turning, wire off). With a voltmeter you should read battery voltage while the starter is cranking. So while running the wire is "live", from the coil, but the switch is off.
 

Howard Sterndrive

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

works perfect now - thanks guys!
 

libellav15

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

That wire is on a terminal where the contact is is only closed when the starter solenoid is activated. As soon as the key is released the contact opens and brakes the circuit. So if you put a ohmmeter on that terminal (to ground) you should read an open circuit (starter not turning, wire off). With a voltmeter you should read battery voltage while the starter is cranking. So while running the wire is "live", from the coil, but the switch is off.



fantastically explained stony - this was bugging me as well - so the starter solenoid powers/switches the 12v supply to the coil when needed - and re-opens the circuit once running and key released to run position.

excellent :)
 

Don S

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

My guess is, the starter probably stayed engaged also. With power fed to the s terminal on the start solenoid, it would have to keep the starter engaged.
 

libellav15

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

ohhhhhhhhhhh Don.....

i just get it clear in my little head and you come along and......................:D

only kidding bud :)
 

libellav15

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

ignore the above Don

just realised you meant in the opening posters case

totally agree

cheers

adam

:)
 

Howard Sterndrive

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Re: Points ignition Mercruiser V6 Ballast resistor... I don't get it??

My guess is, the starter probably stayed engaged also. With power fed to the s terminal on the start solenoid, it would have to keep the starter engaged.

It didn't when I had the wire hooked to the start relay (high amp lug -big 12ga yellow/red wire).. it just shut down when the key was released.

but when I moved the wire to the low current terminal (the one with the little 18ga. yellow/red wire coming from the key switch), then I had the starter cranking as soon as I turned the key on :)

seems the ballast resistor was too much resistance to run the starter solenoid, but not too much to get the start relay to engage
 
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