Loose Dist. Cap blew Ign panel fuse, now won't start, did something else fry?

liquidlew

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1989 Merc 4.3 Thunderbolt, Alpha One. Been running great, started right up as usual, but suddenly died after 30 seconds. Found the Distributor Cap was very loose and guess that is what blew the ign. fuse in the dash panel. Put on new cap and rotor, replaced the fuse and it cranks and gets fuel but will not fire. Tested for spark from coil wire, nothing. Tried a backup coil that is good, still no spark. Is something else fried? Figured I would ask you guys before I break out my Merc manual. Cap and Rotor are new, plugs and wires and battery replaced last season, boat, engine and drive have been running like a dream, haven't had to post here in quite awhile! Thanks in advance!
 

Don S

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Re: Loose Dist. Cap blew Ign panel fuse, now won't start, did something else fry?

Here is the troubleshooting chart for the thunderbolt IV ignition.
I assume when you replaced the cap and rotor you check the module in the distributor for physical damage.


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liquidlew

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Re: Loose Dist. Cap blew Ign panel fuse, now won't start, did something else fry?

Thanks Don! I did not see any physical damage to the module, that would be the black thing (Ignition sensor?) under the rotor? Is that part different from the Ignition Module, as I see 2 different components listed in the chart you gave me? If so, where exactly is the Ignition Module? I will check all this out next day or two when I get a chance, thanks again!!!
 

Don S

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Re: Loose Dist. Cap blew Ign panel fuse, now won't start, did something else fry?

Yes, it's a sensor in the distributor, module is outside. I just used the wrong word.
 

liquidlew

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Re: Loose Dist. Cap blew Ign panel fuse, now won't start, did something else fry?

Gotcha, Thanks! I did these tests, but one confuses me a little. In one box it says to "Check for 1-12 volts at WHT/RED Terminal on Distributor". The wires going into the sensor and the sensor itself are sealed with no exposed contacts to test at the distributor, so how do you make that test? I did unplug the Wht/red wire at the connector and get voltage from the Ign. Module/Amplifier, so I'm thinking the Sensor is bad?
 
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