Spark color
 

From what I understand, a spark at the plug should be a blue color. What I'm getting is a yellow color.

What can I deduct from the yellow color, and is it a problem?

Thanks
EOG

Re: Spark color
 

Ah, that just means you're color blind.

Just kidding.

As long as it seems like a good strong spark you good to go.

Re: Spark color
 

Make sure your point gap is correct.

Re: Spark color
 

A number of conditions can affect the color the plug spark or discharge. The normal color of a spark plug arc should be bluish white. A yellow colored arc could be the result of one or more of the following:
Incorrect electrode gap
Bad coil (secondary shorting internally)
Poor ground to coil
Weak condenser (capacitor)

Re: Spark color
 

How far will the spark jump when holding the coil wire from a head bolt? That'll tell you more than color.

Re: Spark color
 

Thanks for these suggestions.

Sparkplug gap is correct, and new plugs....but, will look into these other things....

eog

Re: Spark color
 

A yellow spark is indicative of a fault in the hi-voltage side of your ignition. The spark color should be violet / purple.
> Check that the coil hookup is correct and all gaps are correct: Plugs 0.035"; Points 0.18" to 0.022"; Rotor 0.010" to 0.15";
> Check that all of the plastic parts (Coil; distributor body; cap; rotor) are clean and there are no sparks / carbon tracks visible;
> Make sure that the distributor body is well grounded
> If the problem continues, try a new condenser;
> Check that the carbon button on the distributor cap is present;
> Also try a new rotor.