Coolant on my spark plugs

[Kevin74]

Hey Guys,

I bought a 67 Charger with a 440. It never did run well, so I left it alone for about 6 months. Now, I’ve got the time and motivation to tackle this problem.

I started by pulling the spark plugs and found some green radiator coolant on the spark plug threads of two adjacent cylinders. The other 6 plugs were fine.

Could it be as simple as a bad intake manifold gasket? Would it be worth trying that? Or do the heads definitely need to come off?
Thanks,
Kevin

 

[R413]

No coolant at the intake gasket of a BB Chrysler.
The problem lies someplace else.

exhaust studs go into coolant, look there before pulling the head.

 

[ChryslerKid]

No coolant passages in the intake of the big blocks.

 

[Aeronet]

Leaking head gasket, hopefully.

 

[BeepBeepRR]

Could be a freeze plug leak or it could be leaking above those 2 spark plugs from the outer headbolts. Also could be from exhaust studs/bolts around or near those two plugs.

 

[Kevin74]

You guys are awesome!
Thanks for letting me know that the intake manifold is a non factor.
I’ll pull the heads, ask a machine shop to check them for straightness, and then reinstall with new gaskets.

 

[ChryslerKid]

Ive never personally seen cast iron heads warp. Buy a cheap picture frame and use the glass to check for straightness. A little gas in a spray bottle helps you see where it touches the glass.

 

[Mick56]

Do a compression check. See if the two adjacent cylinders are low.

 

[Mark Barnes]

Always a good sign. Those cylinders will run much cooler with that water and antifreeze in there.