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mercrusier 160 ignition problems

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aztec21

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I have a 1969 mercrusier 160. Engine has been professionnally rebuilt and I did the removal and install. after 2 years it suddenly quite.
Replaced the ignition switch, ballast resister, and coil. It has a Mallory electronic distributor kit in it. no points. Now, with the key in the on position, I have 12 volts at the starter, 12 volts going to the ballast resister, 5.94 V. at the positive side of the coil and going into the distributor. Removed coil lead to check spark. When key is turned from on to start, it sparks once, then ,continues to turn over but no spark, when key is released from start back to on position , it sparks one more time. thats it,?? nothing in between
Something with the starting system and run systems ?? any ideas
 
with a 6 volt drop across the resistor, I'd say something isn't right with the module in the distributor.....I'd look up the troubleshooting kit for the kit that's in the distributor and go from there.....
 
Replaced the ignition switch

Red to "B" purple to "I", yellow W stripe to "S"

with the key in the on position, I have 12 volts at the starter

So with the key "on" the starter is operating continuously

 12 volts going to the ballast resister, 5.94 V. at the positive side of the coil

Most electronic systems want a full 12volts at the system
 
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should I have 12 V across the resister and then to the coil with the key in "on" position?, and with the coil wire not connected to the distributor I still only have 5.94V at the positive side of coil
 
switch is connected correctly, double checked.
I will check resistor volts again . Should there be 12 Volts on both sides if not cranking.
I wont be able to check until Friday
Thanks
 
most electronic systems require 12 volts at the coil and most electroninc systems use 2 wires from the module to the coil.
The resistor is eliminated . If this the system you have, if not what is the model number for your ign system.
 
Is that one of those deals where the "I" terminal on the starter solenoid sends 12 volts to the coil during cranking? If so, the starter solenoid switch is bad.

Jeff
 
bt doctur
the elcetroninc module does have two wires going to the coil "+" and "-".
The shop that put in the module left the resister in, but, as I have found in reading up on this, the resisiter is there to reduce Volts to the coil.
is that correct? should the resister be eliminated, if so, I think I would need a differenet coil?
 
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BT Doctur
The resister was original to the motor, however It has been replaced with new now.
I will be I will not be able to check more until Friday, will post more then.
everyone gave good responses.

Thank you for the link .
 
with the key on, I have 12.5 volts at the red post of the starter solenoid, but,, the brown wire that comes off of the solenoid and goes to the resister is only 5.6 volts and5.6 coming off resister to the coil. Is it starter solenoid problem?
 
couple things wrong, A white wire is the factory resistance wire if a ballast resistor was used how is it wired.A tan wire comes off the solenoid to give the coil 12v at cranking only. a brown to the shift interupter and another brown goes to the tach.
 
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but,, the brown wire that comes off of the solenoid and goes to the resister is only 5.6 volts and5.6 coming off resister to the coil. Is it starter solenoid problem?

Its a wiring problem, the power for the coil thru the resistor comes from the ignition switch
 
Bt Doctur said:
.
a wiring problem, the power for the coil thru the resistor comes from the ignition switch
Click to expand...

2X...the wire from the solenoid should only supply +12VDC to the coil when the starter is engaged. With the key ON and the engine OFF, there should be +12VDC at the IGN terminal of the ignition switch and 9-12VDC on the coil + terminal....
 
back intown for the weekend, back at the ignition,
picked up a remote switch so I could measure volts cranking.
with key on, volts to start terminal on selonoid is 12.5
brown wire from selonoid to resister 5.6
from resister to coil positive side 5.6
with engine cranking
brown wire from selonoid to resister jumps from 7 to 9 volts
at positive coil , jumps from 7 to 9 volts
any suggestions
 
well, I changed solenoid and resister. voltage is the same, tan wire off selonoid is still 5.5
the differance now is the resister ( both the old and the new, changed them out to test) get hot with in 2 minutes with the key in the on position. started to smoke
I checked the spark using the coil lead to ground, again, and the spark is only once when you first hit the start, leave it turning over for 5 or so seconds, there is no spark, then when I release the key it gives me one spark at the end?? do I have a bad wire in the starting circut?
 
Does the harness still have the resistance wire in it? If so, the other resistor isn't necessary.

The S terminal on the solenoid should get +12VDC until the key is turned to the START position....the Battery terminal (the big one on top) should have battery voltage all the time. The (R or I) terminal will have +12VDC when the solenoid is engaged.

I'd be inclined to think your module is bad based on "the resistor ...started to smoke".....look for the troubleshooting guide for the module you have and follow it....It should have the non-factory wiring needed as well...
 
Remove all the wires on the + side of the coil. Using the resistor ,wire 1 side to the + side of the coil and the other side direct to +battery, check for spark,
Yes, trouble is in your wiring
No, trouble is the module
 
you are hot wiring the ign system and just in case its a tach problem remove all the wires on the negative side except for the module lead.
 
removed neccessary wires,ran wire from bat side of starter to resister, from resister to positive side of coil. no spark.
I have Mallory e spark, 6100M electronic module, will look on line for test procedures from mallory
 
Going on memory, a 6100 uses a shutter setup under the rotor.....the test just mimics the shutter blocking/passing the light....pretty straightforward....the test details the other measurements to make to identify the faulty part....
 
redid test, ran wire from batt to resister, from other side of resister to positive coil , 12.5 volts on resister from batt, 5,6 on other side of resister and on to coil positive 5.5 ,coil lead 5.5 volts. does not change volts when cranking, remains 5.5
no spark
 
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