Lap the valves, put fresh valve seals in, clean them up and have at it...

 

looks lean to me, im with Ben, clean them and put them on the 6.0

 

Looks kinda norm to me. Some could have to do with the type of gas being run, but that looks to me like it is working exactly the way it should be.. Lets not forget that exhaust valves get a good bit hoter then intake valves, are made of diff material alot of times.. So the colors they change will be diff.. Clean them up and roll with it..

 

I will try to round up some pics from my heads off the boat.. Same way.. Its all good

 

Yes, youre fine. Thank all the additives in your gas with the addition of Ethanol.

 

Where's richard when you need him?

 

iam no expert but once i started running c12 on my yfz my complete exhaust turned white like so, i hade a buddie take the heads off and the exhaust valve look the same as the pics everything else seem perfect ive , its been 2 years since and ive never have had a problem!

 

....IT IS OK....

 

Yeah, something in your gas. If an engine ran so lean that it burnt carbon into white ash, your pistons would have holes in them.

 

I've seen exhaust valves on multiple manufacturer's stock heads, 4 cyl, 6 cyl, and 8 cyl, that look exactly like that and never even think twice about it