<VV> Weird ignition troubble

[Larry Forman]

Hi Daniel, See reply within text.  -- Larry
> ----- Original Message -----
> From: "Daniel Monasterio" <dmonasterio at megared.net.mx>
> >      Well, today, in a attempt to check how well every 
> piston/chamber was working, I warmed engine, attached a tachometer 
> and (engine running at 900 rpm) began to dissconect plug wires at 
> distributor cap to notice how much rpm dropped without every 
> certain spark plug working. 

I always caution everyone to SHORT the plug wires to ground rather than pulling them.  I have had people tell me that they have done it the "pulling" way for decades without troubles.  The problem with that approach is that the ignition voltage will climb to WHATEVER is needed to continue the current to flow until the energy is gone.  This means that the pulling approach places tremendous electrical stresses on the ignition components, especially the ignition coil and even more so to any electronic ignition system components, aka Pertronix.  I prefer to use a well grounded clip lead with a straightened paper clip in one end, pull back the rubber nipples on the distributor cap and short each plug wire to ground.  That is quite quick and does not subject the sensitive electronic ignition systems to excessively high voltages.   You might have damaged the Pertronix, not sure.  Swap back to points and get running well and then replace Pertronix, retime and see.

>      BTW, coil is matching Flamethrower with straight 12V. source.
> 
>      Any toughts ?... thanks in advance for every neurone working on this.

If you STILL have an issue where you need to advance or retard the ignition from where you think it should be AND have exhausted every other idea, like a slipped harmonic balancer and worn cam lobes, running with points, etc., then it might be time to see if the CRANK gear has slipped or the crank and cam gear alignment is not right.  I had that happen on an unknown history 140 and I spend months trying to determine why it needed wildly changed timing to barely run.  The checking approach is in the CORSA Tech Guide under "Finding that darn cam mark" or something like that name.  You rotate the engine to TDC compression stroke on #1, drain the oil and drop the oil pan and look from the front of the engine bottom backwards at the cam gear.  If the cam gear timing mark is lined up with the case split, then the crank and cam gear are properly aligned AND the crank gear is still where it should.  Mine was off about THREE or FOUR TEETH(!) and that explained why the engine barely ran.  This might have happened if the PO banged the car when it was in gear thus spinning the crank gear from it's normal location.  Note that I had previously pulled the bell housing to check the cam to crank gear alignment and it was PERFECT,  This is one of those last resort checks, although it is not to difficult to do and not too time consuming.
-- Larry  
> 
>      Daniel