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Re: flacky pertronics?



The aliens commander decided Tom Mandera <tsm1@domain.elided> would make a
perfect specimen for dissection, and he yelled...

>If you left the resistor in place, you should've been fine...

Wait a minute!  This depends.

Eric... The bottom line is this...

The Pertronix cannot handle "switching" full or nearly a full 12 volts
coming through the coil.  That much voltage will cause the Pertronix to
overheat and fail at some point, just like breaker-points will arc, burn
and fail in time if fed too much voltage.

So just like breaker-points, the Pertronix needs to be protected from
excessive voltage by the higher resistance of a stock type coil *or* by the
resistance of an external ballast resistor / resistance wire in the
ignition circuit.  The Pertronix does not need both.  Using a higher
resistance stock type coil *and* an external resistor could mean inadequate
secondary spark being developed in the coil... which means a you could get
a weak spark at the spark plug tip.

If you're sure that coil is a stock version (verify by checking the
resistance across the small primary terminals on the coil per the Pertronix
instructions), then do *not* use a ballast resistor also!  If the coil has
low resistance (as is typical with aftermarket high-performance coils such
as the MSD Blaster, etc.), then you must use a ballast resistor to increase
the resistance and protect the Pertronix.

Before you yank the Pertronix assuming it's the culprit, check some basics.


1. Verify the coil is actually a stock type and if so, disconnect the
ballast resistor.  However, I'd recommend you physically leave the ballast
resistor in place in case you do need to drop the points back in someday.  

2. For best results, make sure the red power supply wire from the Pertronix
is connected to an ignition switched *full* 12 volt power source... not a
lower voltage source after the ballast resistor.

3. Verify the air gap is correct between the magnet wheel and the Pertronix
module.

4. Make sure the magnet wheel is not loose and free to move around under
the rotor.

5. Check all of your, and the old previous wire connections in the ignition
system are clean and solid.

There's always the possibility the Pertronix module is having problems, but
this is extremely rare, so I'd really check things out carefully first
before focusing on it.  You'd be terribly aggravated if you had it replaced
by Pertronix only to find the problem still there.

Good luck,

John L.
-------------------------------------------------------------------------- 
jlandry AT halcyon DOT com      | 
Conservative Libertarian        |  "The road to  tyranny, we must never
Life Member of the NRA          |   forget, begins with the destruction
WA Arms Collectors              |   of the truth."
Commercial Helicopter - Inst.   |                     William J. Clinton
http://www.halcyon.com/jlandry/ |    10-15-95, speech at the Univ. of CT



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