Melted coil feed wire = Bad Pertronix?

[Lancer76]

Ford 351W (Mercruiser 233). Been slowly chasing down some starting/wiring issues. Present head scratcher is that when I apply 12 V to the coil via the electric choke, the wire from the choke to the positive on the coil got hot enough to melt the wire sheathing on the short stretch from the choke to the coil. It's not a resistance wire - I removed that when I installed the pertronix 1 system. Coil ohms out fine at 1.6 ohms on the primary and 10.6k ohms on the secondary. No short to the coil case. Disconnected from the coil, I read 12v through the wire from the choke to the end of (melted) wire with power on. This is all while engine is not running. Does this suggest a bad pertronix 1 module in the distributor?
I should state that I've run this Pertronix system for a few years, but did not encounter this issue.
Thanks.

 

[ROY WILLIAMS]

THE MCM470 engine year 1978 . the pertronix 1146A in the distributor . the resistor wire of the choke 1.6 ohms of the coil positive ...I was doing it over 13 yrs ago...
then the engine is a carb of the gasoline and the engine rpm dropping ..
the ignition key is turning on the key, the engine is not running ... it of the carb area .. then the pertronix is damaged of the 30sec of the key ignition on and the engine is not running ...
now the new pertronix 1146A in summer .. engine is a very good job ..
your key is the 30 sec on the engine not running ..
now my coil is 1.2 ohms pos and neg ... then the 10K ohms or the high voltage distributor ,,,,.
you the resistor wire is the insulator very hot of melted it ....

 

[Lancer76]

So to summarize, are you saying the Pertronix is bad?

 

[dubs283]

A melted wire would indicate a short to ground, my first guess would be the choke. Otherwise the bypass wire as part of the original system could be an issue.

Not too sure where the bypass wire is connected but on some its from the primary side of the slave solenoid or the excite circuit from the alternator

 

[ROY WILLIAMS]

So to summarize, are you saying the Pertronix is bad?

the ignition key is on and the engine is off ,,, around 30sec - 1 minute then the pertronix is the damaged ..
also the ignition coil is the purchased it coil ...
so you was the pertronix of the wires and then that cap distributor ...you was the cap of the wires of the metal ? I was the plastic cap of the pertronix wires and then the file is the cap did the passage of the wires close of the port hole file ..
also the pertronix new ...

 

[nola mike]

Disconnecting the neg side of the coil will eliminate anything upstream as the problem. Is the wire still getting hot? Possible that the tach/wire is shorted to power, but not sure what the exact issue would be if that happened. You can also connect an ammeter in line to see where your increased current draw is coming from

 

[ROY WILLIAMS]

THE MCM470 engine year 1978 . the pertronix 1146A in the distributor . the resistor wire of the choke 1.6 ohms of the coil positive ...I was doing it over 13 yrs ago...
then the engine is a carb of the gasoline and the engine rpm dropping ..
the ignition key is turning on the key, the engine is not running ... it of the carb area .. then the pertronix is damaged of the 30sec of the key ignition on and the engine is not running ...
now the new pertronix 1146A in summer .. engine is a very good job ..
your key is the 30 sec on the engine not running ..
now my coil is 1.2 ohms pos and neg ... then the 10K ohms or the high voltage distributor ,,,,.
you the resistor wire is the insulator very hot of melted it ....

the error of the resistor wire 1.6 ohms , the resistor wire is 1.8 ohms .

 

[Lancer76]

Disconnecting the neg side of the coil will eliminate anything upstream as the problem. Is the wire still getting hot? Possible that the tach/wire is shorted to power, but not sure what the exact issue would be if that happened. You can also connect an ammeter in line to see where your increased current draw is coming from

I will try this. It's a good idea (disconnecting the ground side of coil). I did disconnect the "melted" wire from the positive side of the coil. With power on, 12v to the end of that wire, but not getting hot.

 

[Scott Danforth]

I have never had good luck with pertronix. YMMV

 

[Lancer76]

the ignition key is on and the engine is off ,,, around 30sec - 1 minute then the pertronix is the damaged ..
also the ignition coil is the purchased it coil ...
so you was the pertronix of the wires and then that cap distributor ...you was the cap of the wires of the metal ? I was the plastic cap of the pertronix wires and then the file is the cap did the passage of the wires close of the port hole file ..
also the pertronix new ...

I think I got you, Roy. Thanks for the info.

 

[nola mike]

I will try this. It's a good idea (disconnecting the ground side of coil). I did disconnect the "melted" wire from the positive side of the coil. With power on, 12v to the end of that wire, but not getting hot.

It will show voltage but won't get hot because there isn't current through the wire. Reconnect it to the coil, disconnect neg wires and try again. If still good connect negatives one at a time.

 

[ROY WILLIAMS]

It will show voltage but won't get hot because there isn't current through the wire. Reconnect it to the coil, disconnect neg wires and try again. If still good connect negatives one at a time.

I was the igniter pertronix in the cap , and 2 wires in the cap distributor ...
then the metal is the wires ... the cap is a wires area , and the filed it of that hole distributor plastic cap .
troubleshooting of the shorted pertronix wires ..

 

[Masinc]

I will try this. It's a good idea (disconnecting the ground side of coil). I did disconnect the "melted" wire from the positive side of the coil. With power on, 12v to the end of that wire, but not getting hot.

I have ATK marine 351w in my 67F100 with same ignition system. Started out good then went bonkers twice. Go to Summit Racing sight and do some digging. You will find a correct ohm (much better) coil and with a little more digging a replacement “module” (very small price) and I bet it will work fine. Also if you ever mess with the gutts of that dizzy you gotta be absolutely sure you have every thing in perfect position or it will eat it’s self. Now thats just from my experience only. Mine has worked great since and tows the SeaRay 220 just fine now.

 

[Masinc]

Maybe not even the problem but I keep an extra one of these and some zinc thermal paste in the glovebox just in case.

 

[ROY WILLIAMS]

Maybe not even the problem but I keep an extra one of these and some zinc thermal paste in the glovebox just in case.

I was my 1996 Impala ..... I was the ICM and the coil ignition ... fixed it of the thermal paste ... I was the liquid paste of the coil ignition ... did a very good job .... nov 1995 - todays engine ...

 

[ddrieck]

You need 12v to the coil, make sure it is not running off the reduced 6.whatever voltage the original point ignition used.
Also, pertronix needs to use a 3ohm coil, mine came with the 3ohm flamethrower coil.
This is on my 1986 Mercruiser 470

 

[ROY WILLIAMS]

This is on my 1986 Mercruiser 470

I was the MCM470 engine 1978 ... the manual of the engine flat taps ....
I was my zinc plus additive 5OZ. engine oil ....
back of the engine oil is the zinc engine oil .. the automobile engines 1970's and older ... flat taps ...
the GM older decades the steel engines of the crank case , cam shaft .
the newer engines are the solid metal surface ...very strong metal coating ..
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