Hey Bill....Having trouble reading plugs

[Starkna]

Bill,
Have a 99 xpl and i'm trying to tune it in...The insulators look good....but i'm having trouble reading a mixture level off the ends of the plugs. The threads so plenty of moisture(oil/gas)......but the outer ring really is hard to tell how wet it is....even when i richen it up. It will hold 6950-6970 at wot.....sometime it wil drop 10 rpms on an extended run but will come back up.....I just need some help on getting the most out of it. I assume the threads don't tell me what i need to know...??????????????

[Bill O'Neal]

What ? Reading the threads ? The threads are on the outside of the plug, in no place where combustion is happening.

If your motor is turning 6970, that isn't too bad ( about 150 rpm over stock). In fact may be really good if the density altitude is not real good.
Keep in mind that if you tune it to a "tee", and the weather changes drastically for the better, you could get into trouble and melt a piston.

Without knowing your exact setup, prop, ect. I really cannot make an intellegent comment about wether or not 6970 rpm is where you should be, or not.

If your sparkplugs are brownish in color, you are probably pretty well setup and adjusted.

[ June 04, 2003, 08:30 AM: Message edited by: Bill O'Neal ]

[Starkna]

Sorry for the confusion,...had always been told to also keep an eye on the last threads of the plug along with the tip. I'm just having trouble getting them to color up....and was just wanting to know if you had any advice....maybe hold the WOT run a little longer?

[Bill O'Neal]

New sparkplugs, when the motor is jetted and adjusted correctly, take awhile to get color. How long have you been running it with these plugs in it?

[Starkna]

probably 3 or 4 hours on those plugs.....and i think with all the pulling of them and wiping them off.....it's not allowing them to color up....I'll try some new ones