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cranks like a champ but won't start

Kadoom

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project boat-1986 renken 235 cutty-mercruiser 4.3 v-6 omc outdrive. Did start before! No spark at external coil! Tested Ohms-OK! 2 wires to "+" and 3 wires to "-" on coil. Will start if I run a jumper wire from "+" battery to "+" coil! How or what can I test next? Your help is needed!!!!
 
project boat-1986 renken 235 cutty-mercruiser 4.3 v-6 omc outdrive. Did start before! No spark at external coil! Tested Ohms-OK! 2 wires to "+" and 3 wires to "-" on coil. Will start if I run a jumper wire from "+" battery to "+" coil! How or what can I test next? Your help is needed!!!!

Ayuh,.... Sounds like the ignition circuit is dead, start at the key switch, 'n work back,...
 
Will start if I run a jumper wire from "+" battery to "+" coil! How or what can I test next? Your help is needed!!!!
Are you saying that it will start with the + side of the ignition coil "jumped", and that the "jumper" needs to remain?
Or...... are you saying that the once fired up via "jumping" the + terminal, it will remain running without the "jumper"?

If it continues to run once started up and without the jumper wire, then you likely have an issue with the "Start-by-Pass" circuitry.




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would not turn off by turning the key off! but with the key in the off position and removing jump wire it stopped!
 
2X what bondo said....

If it has a ballast resistor, I'd start with it...follow the two wires from the "+" side of the coil.....one will go to the starter's solenoid and the other should go back to the resistor, and from there to the key switch....
 
would not turn off by turning the key off! but with the key in the off position and removing jump wire it stopped!
Please read post #4 again.

I'm not concerned with the jumper preventing the key switch from killing the ignition.
It only makes sense that the jumper would by-pass the key switch power, and render the key "OFF" an unusable function.

I'm more concerned with just how the jumper is affecting the spark, and the answers to my 2 questions in post #4.


BTW, if you do have the lanyard switch at the helm, the clip must be in position.
Check the continuity of this kill switch! By-pass it temporarily if need be.
Your VOM will be your friend!

And also (as mentioned) check the continuity of any Ballast Resistor that may in the ignition circuit.



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Sorry , but you guys are dealing with a novice boat electrical repair person! Ignition switch does NOT have a lanyard kill switch! Ignition switch has 4 wire connectors with a fuse mounted on dash next to the key! How do I test at ignition switch? This is a 2 barrel carb with points and condenser! Are there any "kill" alignments on the throttle or at the forward and reverse cables mounted on the block? What is the function of the mirco-switch at the cable mount location? I am going to replace the tack wire from the dist. to the coil and also try to find the ballast resistor and hopefully test it! I am hope this info will help you guys help me!!!! Thanks again!!!!
 

Ditto to what Kim just posted.


Sorry , but you guys are dealing with a novice boat electrical repair person! Ignition switch does NOT have a lanyard kill switch! Ignition switch has 4 wire connectors with a fuse mounted on dash next to the key! How do I test at ignition switch? This is a 2 barrel carb with points and condenser! Are there any "kill" alignments on the throttle or at the forward and reverse cables mounted on the block? What is the function of the mirco-switch at the cable mount location? I am going to replace the tack wire from the dist. to the coil and also try to find the ballast resistor and hopefully test it! I am hope this info will help you guys help me!!!!
OK... no lanyard style kill switch!

Before you replace the tach circuit, just disconnect it and give things a try.


1986 renken 235 cutty-mercruiser 4.3 v-6 omc outdrive.

In 1986 this may be an OMC Stringer Drive.
If memory serves me, 1987 was when the OMC Cobra drive found it's into the market place.
Your OMC drive may be a Cobra drive... or may be a Stringer Drive.

Here's a Stringer drive.

OM-SDC.gif


Here's a Cobra drive.

MICHAEL%20HASSEN.JPG


A Dog Clutch drive requires a momentary reduction in RPM in order to achieve "neutral" from when "In-Gear" and while running.
OMC used what's called an ESA (electronic shift assist) that accomplishes this by stumbling the ignition system momentarily while the Dog Clutch is being released.
This would be the "micro switch" that you asked about.
The ESA requires a somewhat critical adjustment... and it must be made while in the water.

As mentioned, you'll likely have a "Start-by-pass" circuit as well.
This
"Start-by-pass" circuit supplies a full 12 v to the ignition coil during cranking ONLY.
If the jumper is required to start up.......... your
"Start-by-pass" circuit may not be working correctly.

Hence my two questions in post # 4.

I can't be of much more help until these are answered.




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starts with jumper from positive battery to positive on coil. Will only shut down when jumper is removed! This is(according to your pictures) a corbra drive.
 
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