Glowing Spark plug

GoldenMotor.com

holloran

New Member
Aug 18, 2009
3
0
0
st. louis, mo.
I was riding my bike for about 20 min and heard some pinging looked down and spark plug was glowing like an orange light. What would cause this and how do I fix it? Thanks for any help. It's a 66/cc motor with a slant head
 

diceman2004

New Member
Aug 26, 2009
564
2
0
Kitchener , Ontario
AND THE HEAD DIDN'T MELT ?

Thats a lot of heat , way too lean or you have an air leak between the carb and tube , or the intake gasket is leaking air . ( thats my thought )
But i'll bet after that much heat , theres probably some kind of damage now .

You didn't give a lot of info to go on , new motor ? old motor ?
you did mix oil in the gas , right ? Not much i can tell ya .

You will have to try to ( carefully ) get the plug out , once it cracks loose .
I wouldn't try using that plug again .
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
A steel spark plug hot enought to glow? And the engine still ran? The aluminum cylinder head is still intact? We need a little proof here if you please.
Tom
 

Allen_Wrench

Resident Mad Scientist
Feb 6, 2010
2,784
26
36
Indianapolis
Steel that is glowing orange is in the neighborhood of 1700 degrees Fahrenheit. Not yet melting, but pretty doggone hot. Basic old cast aluminum melts at 1220.58 Fahrenheit. So here I am at a loss. We might assume that your head is not pure aluminum, nor your jug, nor your piston. Or we may instead want to assume that, if it is true that the spark plug was glowing like a lit stogie, although the head, jug, and piston might seem fine, they are likely ready to blow next time you fire it up. If none of these things is the case, then I just dunno.
 

MotorNut123

New Member
Aug 31, 2010
220
0
0
New York
well that is a case of running way lean. and i cant believe it didnt melt the cylinder! i would check out the piston and cylinder walls for any cracks or wear. pics would be awesome. never saw that before