semlin
curmudgeon
On a 3FE motor with 150k, the #3, 4 and 5 plugs all have a crusty build up on one side of the arm and around the ceramic insulator. It is hard to tell but the ceramic on a couple of the insulators may actually be burnt or maybe just stained.
The other three plugs are not bad but have some light crusty build up and discolouration and generally are black not brown.
According to a generic spark plug inspection charts this symptom is either carbon build up or ash from burning oil that is getting in through the valve seals or rings. Generic suggestions include check timing, plug wires and distributor, techron gas treatment, and increasing oil viscosity followed by more serious surgery.
Right now it contains 10W-30 dino oil and has been using more oil lately.
The plug wires, caps and rotor are all nearly new. It has the factory spec NGK plugs and they are 6 months old.
I am thinking switch to 20-50 or 0-40 synthetic, try the techron stuff, check the timing and do a compression test. Any other suggestions?
The other three plugs are not bad but have some light crusty build up and discolouration and generally are black not brown.
According to a generic spark plug inspection charts this symptom is either carbon build up or ash from burning oil that is getting in through the valve seals or rings. Generic suggestions include check timing, plug wires and distributor, techron gas treatment, and increasing oil viscosity followed by more serious surgery.
Right now it contains 10W-30 dino oil and has been using more oil lately.
The plug wires, caps and rotor are all nearly new. It has the factory spec NGK plugs and they are 6 months old.
I am thinking switch to 20-50 or 0-40 synthetic, try the techron stuff, check the timing and do a compression test. Any other suggestions?
