Amigoboomer
Recruit
- Joined
- Jul 12, 2009
- Messages
- 1
I've been tracking back thru this thing for the last three weekends and have been stumped as I try to determine where the issue is.
Before I begin - I'm armed with Multimeter and a Clymer OMC Cobra service manual (which isnt the most helpful thing around). Got the boat itself last September and it was running prior to being pulled from the water so I know it's capable of running.
I charged up the battery - a marine deep cycle 12V - on a trickle charger. Had 230A on load before - didnt check cranking amps after though...
After getting a sticky safety switch figured out, got the engine to turn over on Start - but no spark at plugs. Fresh gas in tank so that wont be it.
Engine cover off and started diagnostic. Start my own with checking if I'm getting gas into the intake - yes, check.
Remove plug #3 from cylinder and hold next to block - no spark...
Remove wire from distributor cap and hold next to block - no spark...
Resistance across primaries on coil - 1.6 ohms (good according to Clymer)
Resistance across primary to secondary - negative is 7.8kOhms, positive is 0. (according to Clymer schematic, the primary and secondary share positive terminal and should be 0)
Start checking the point gap - there is one and seems good according to spec in the book
I have a spare distributor from the prior owner (something about doing full oil changes causes issues with the distro? not sure but hey, whatever) so I switch out the condensers. Still no spark from the secondary...
Start running down the Troubleshooting flow chart - basically repeating the above until I get to checking voltages between ground and each of the primary terminals. Get a voltage from negative to ground - tells me to replace coil...
I replace coil.
No spark still.
I start checking back to the connectors between Overstroke and Interrupter switches - which is in one heck of a place to get to. I read that if either switch is hosed then the motor could likely stall. I'm now looking to disconnect the ESA module (since I read somewhere to give that a try).
With points and condenser ignitions not being rocket science - I'm totally out of ideas at this point. Now I did read that the circuit that the coil/distro are on when key is in Start position is a different one than when it's in On - where and how do I check if this relay or solenoid is flipped one way or the other when the key turns? Also, is there anything like a "dead man switch" which would or could flip off and then ground the ignition circuit here? The schematic is brutal in it's simplicity and non standard electrical drawing (i.e. its missing the ballast resistor which has me thinking there is none, but the resistance from primary negative coil to distro is 4 ohms so there has to be one...
Thanks in advance!!
Rob
Before I begin - I'm armed with Multimeter and a Clymer OMC Cobra service manual (which isnt the most helpful thing around). Got the boat itself last September and it was running prior to being pulled from the water so I know it's capable of running.
I charged up the battery - a marine deep cycle 12V - on a trickle charger. Had 230A on load before - didnt check cranking amps after though...
After getting a sticky safety switch figured out, got the engine to turn over on Start - but no spark at plugs. Fresh gas in tank so that wont be it.
Engine cover off and started diagnostic. Start my own with checking if I'm getting gas into the intake - yes, check.
Remove plug #3 from cylinder and hold next to block - no spark...
Remove wire from distributor cap and hold next to block - no spark...
Resistance across primaries on coil - 1.6 ohms (good according to Clymer)
Resistance across primary to secondary - negative is 7.8kOhms, positive is 0. (according to Clymer schematic, the primary and secondary share positive terminal and should be 0)
Start checking the point gap - there is one and seems good according to spec in the book
I have a spare distributor from the prior owner (something about doing full oil changes causes issues with the distro? not sure but hey, whatever) so I switch out the condensers. Still no spark from the secondary...
Start running down the Troubleshooting flow chart - basically repeating the above until I get to checking voltages between ground and each of the primary terminals. Get a voltage from negative to ground - tells me to replace coil...
I replace coil.
No spark still.
I start checking back to the connectors between Overstroke and Interrupter switches - which is in one heck of a place to get to. I read that if either switch is hosed then the motor could likely stall. I'm now looking to disconnect the ESA module (since I read somewhere to give that a try).
With points and condenser ignitions not being rocket science - I'm totally out of ideas at this point. Now I did read that the circuit that the coil/distro are on when key is in Start position is a different one than when it's in On - where and how do I check if this relay or solenoid is flipped one way or the other when the key turns? Also, is there anything like a "dead man switch" which would or could flip off and then ground the ignition circuit here? The schematic is brutal in it's simplicity and non standard electrical drawing (i.e. its missing the ballast resistor which has me thinking there is none, but the resistance from primary negative coil to distro is 4 ohms so there has to be one...
Thanks in advance!!
Rob