[Top] [All Lists]

Re: It doesn't even sputter...

To: "W. R. Gibbons" <>
Subject: Re: It doesn't even sputter...
From: 007 <>
Date: Wed, 3 Apr 1996 08:23:30 -0800 (PST)

On Tue, 2 Apr 1996, W. R. Gibbons wrote:

> On Tue, 2 Apr 1996, David E. Brown wrote:
> > when I did see some spark at the plug.  At this point, with a new 
> > coil and ballast resistor, I have no spark even from the coil lead 
> > to ground, but the coil primary (switch side) has power.  I don't 
> > get it.
> Part of this should be easy to trouble shoot.  You have a new coil, and 
> power to the coil primary.  If the coil is good and has power, then you 
> have to have a fault in the circuit through the points. This circuit 
> makes a circuit through the coil primary to ground when the points close 
> and disconnects the circuit when the points open.  The changing voltage 
> in the primary induces a higher voltage in the secondary.  If no current 
> flows through the primary, or if it always flows through the primary, 
> there will be no spark.
> Disconnect the lead from the coil to the points.  Take a jumper wire,
> attach it to the points side of the coil primary.  With the ignition on,
> and power to the other side of the primary, momentarily ground the other
> end of the jumper wire to the chassis.  Have an assistant hold the coil
> center wire an eighth inch from ground and look for a spark.  If no spark,
> your new coil is faulty. 
> If you do get a spark that way, I would bet either your points are not
> opening, your condensor is shot, or there's a permanent short to ground,
> or a permanently open circuit (for example, oxidized points) in the circuit 
> that goes through the distributor, the points, and to ground. 
> It should be fairly easy to check all these possibilities.
>    Ray Gibbons  Dept. of Molecular Physiology & Biophysics
>                 Univ. of Vermont College of Medicine, Burlington, VT
>         (802) 656-8910

My 79 B w/electronic ignition had a similar problem - spark coming from 
the coil (as verified by holding the coil wire close to the block), but 
no spark to the plugs - problem turned out to be a carbon track on the 
rotor - electricity will take the path of least resistance, and the 
carbon track was shorting the spark to the conter of the distributor.  
Replacing the rotor cured the problem - a visual inspection should give 
you an idea if thats it.

Good luck...

Jim Mellander

<Prev in Thread] Current Thread [Next in Thread>