4.3LX ignition question

[ryan04]

Hey guys, in my quest for a smooth running boat I pose this. I have a 1996 4.3LX gen+ thunderbolt 5. I just did a bit of a tuneup chasing down a mild vibration at 2700rpm. I replaced all plugs,wires,dist cap and rotator "thingy" inside, ignition coil, starter, and slave solenoid. She fires up first turn with a lot of vigor now. My first question is, when I have the key to run position and the buzzer is sounding, my voltage reads around 11volts on a fully charged battery. Volt meter on battery and in dash confirms full 13v. When in the run position if I switch the kill switch "off" the buzzer sound goes higher and my voltage reads 13v. So I checked voltage at the new coil positive and I get 11V. But when it's running the voltage on the coil is the 12.5 as it should be. It starts perfectly with no lag, and jumps to life, so the low voltage on the coil isn't causing that much of a problem? I've checked the kill switch, the wiring from kill switch to the dash, the buzzer, and the ignition switch. They all check out fine. The only weird thing I can find is the grey wire on the negative terminal reads 10.5ohms when checking continuity with ground, not zero or 1ohm even. But the grey wire itself shows zero ohms, along with the black grounds on the ignition module. I've cleaned and triple checked all grounds and they appear good. Should I run a new ground to the coil?

 

[Bondo]

Hey guys, in my quest for a smooth running boat I pose this. I have a 1996 4.3LX gen+ thunderbolt 5. I just did a bit of a tuneup chasing down a mild vibration at 2700rpm. I replaced all plugs,wires,dist cap and rotator "thingy" inside, ignition coil, starter, and slave solenoid. She fires up first turn with a lot of vigor now. My first question is, when I have the key to run position and the buzzer is sounding, my voltage reads around 11volts on a fully charged battery. Volt meter on battery and in dash confirms full 13v. When in the run position if I switch the kill switch "off" the buzzer sound goes higher and my voltage reads 13v. So I checked voltage at the new coil positive and I get 11V. But when it's running the voltage on the coil is the 12.5 as it should be. It starts perfectly with no lag, and jumps to life, so the low voltage on the coil isn't causing that much of a problem? I've checked the kill switch, the wiring from kill switch to the dash, the buzzer, and the ignition switch. They all check out fine. The only weird thing I can find is the grey wire on the negative terminal reads 10.5ohms when checking continuity with ground, not zero or 1ohm even. But the grey wire itself shows zero ohms, along with the black grounds on the ignition module. I've cleaned and triple checked all grounds and they appear good. Should I run a new ground to the coil?

Ayuh,.... The grey wire is the Tach,..... Donno why yer seein' the variation,....

 

[ryan04]

so was that a "ayuh you need to run a new ground cause the readings are weird" or a "ayuh that's the tach not a ground?" I'd hate to run a new ground and short something. thanks

 

[alldodge]

Hey guys, in my quest for a smooth running boat I pose this. I have a 1996 4.3LX gen+ thunderbolt 5. I just did a bit of a tuneup chasing down a mild vibration at 2700rpm. I replaced all plugs,wires,dist cap and rotator "thingy" inside, ignition coil, starter, and slave solenoid. She fires up first turn with a lot of vigor now. My first question is, when I have the key to run position and the buzzer is sounding, my voltage reads around 11volts on a fully charged battery. Volt meter on battery and in dash confirms full 13v.

Which is reading the 11V on the battery, your dash gauge or the hand held volt meter?

When in the run position if I switch the kill switch "off" the buzzer sound goes higher and my voltage reads 13v. So I checked voltage at the new coil positive and I get 11V. But when it's running the voltage on the coil is the 12.5 as it should be. It starts perfectly with no lag, and jumps to life, so the low voltage on the coil isn't causing that much of a problem? I've checked the kill switch, the wiring from kill switch to the dash, the buzzer, and the ignition switch. They all check out fine. The only weird thing I can find is the grey wire on the negative terminal reads 10.5ohms when checking continuity with ground, not zero or 1ohm even. But the grey wire itself shows zero ohms, along with the black grounds on the ignition module. I've cleaned and triple checked all grounds and they appear good. Should I run a new ground to the coil?

The tach reads pulses coming from the opening and closing of the control module putting the negative side of the coil to ground. The pulses of the coil causes the primary winding to discharge into the secondary and this provides the spark

 

[ryan04]

excuse this follow up question but, if i was to run a new ground to the engine block from the negative side of the coil would that disable the coil all together? If the pulse from the module grounds the coil to activate the discharge then running a ground would put the coil in a situation of never charging up in the first place? Is this some what accurate? feel free to call me a moron! haha

 

[Bondo]

excuse this follow up question but, if i was to run a new ground to the engine block from the negative side of the coil would that disable the coil all together? If the pulse from the module grounds the coil to activate the discharge then running a ground would put the coil in a situation of never charging up in the first place? Is this some what accurate? feel free to call me a moron! haha

Ayuh,.... If ya Ground the coil, it can't Ever fire,....

 

[ryan04]

K, I'll run a new grey wire to my tach instead. The existing grey must be shorting somewhere on ground if I'm only getting 11v at the coil, and 10ohms to ground.