spark plug discoloration

[johnnybee]

hello got a 283 that was smoking after rebuild. theres an story regarding new engine (283) smoking in custom and classic trucks. my smoker has got better, but im getting discolored spark plugs. none of them are wet. some are normal grey color, but ive got some that are half white and half yellow with some red. i remember seeing charts defining spark plug diagnosis and cures. any one know about this color change, or definition? im useing champion rj12yc plugs. is there a better plug? did any one see that chevy 6 lug 15inch stock wheel on ebay go for 66 bucks. wow you would think there would be a zillion stock wheels out there. i bet a bunch went to scrap. thanks john.:7

 

[ljw]

white spark plugs usually mean you have too lean combustion going on,and as far as know may cause valve damage.Ever think of getting professionally tuned/checked with an analyzer? In regards to wheels,most were tossed long ago,but there seem to be quite a few in Arizona.The only problem is that they are so heavy-they cost more to ship than they are worth to start with.There are companies that can supply wheels that will accept the original caps that are aftermarket-so no rust to strip-only powder coat to apply.

 

[johnnybee]

had a local shop set dell and timing along with carb adjustments.those half red and white ones are kinda strange. does the red color indicate coolant, or maybe to hot? the 283 has a mild cam, a two barrel carb. runs 170 180,degrees and 200 in stalled traffic.the side that had the odd colors have that butterfly restricter on the manifold. maybe its stuck? is it even needed? dont the name of that part. got to watch out for those valves,thanks for your help ljw. john

 

[ljw]

if you are referring to the heat riser valve,it's only purpose is to warm manifold air on cold days.I live in Arizona,and didn't feel too bad about losing mine. check yours that you can turn it by hand against spring pressure.If it doesn't rotate,it is a problem to be fixed.

 

[rebarjoe24]

Do the plugs have a glazed apperance? Normal plugs have a tan to grayish color with slight deposits. Glazing happens with hard, fast acceleration, plug temp. rises suddenly. Deposits from normal combustion have no chance to fluff-off, instead they melt on the insulator. You can try a plug with a heat range one step cooler.

 

[johnnybee]

thank you all for the information.john