Changed my plugs yesterday and noticed that 2 of them have white fouling with some white specks on them as well. There were also 2 of them that weren't as bad but had some specks on them. The others looked normal. Is this coolant fouling like I suspect it is? I have been loosing coolant but my t-stat housing was leaking, which is now fixed. I have that ire inkling that my heads my have cracked.

 

Just looks like ash to me. How old are they? All in all, if the rig is running fine, it isn't the plugs.

IndyD

 

that looks pretty normal to me too, i wouldnt worry about it unless there is a problem, if you had a cracked head im pretty sure you would be missing on one or more cylinders

 

I think what you are seeing is unburned fuel creating the ash and rust colored deposits. Where do you fuel up and what octane are you using?

Also looks to me that you used a fuel cleaner or additive?

Is that a 5.9L?

 

Looks like Champion 5.2 plugs to me.

IndyD

 

If it is ash it could be oil but from what i can see it looks normal. If you really want to be sure get yourself a compression tester and check all of the cylinders compression paying close attention to the two cylinders that the plugs came from. I wouldn't be too concerned with a blown head or head gasket though.

 

Um......Same plug?

Champion Cooper Plug #RC12LC4

 

looks like over heating.. did you let your reservoir tank run dry ever?? I had the same on my far back plugs when I was driving on a bad water pump for a month or two.. just replace the plugs and be happy.. if you had oil or coolant entering the cylinder at a large rate you would have a few more indicators then just a white and ashy plug..

 

Oil leaves a black mark on the end and I don't see that.


As for running hot, I can see that. Good call!

 

I'd rule out fouling, and overheating.
Fouling will be a dark flat black deposit and or covered in oil
Overheating would cause a glazing of the insulator

http://www.ngksparkplugs.com/tech_su...qs/faqread.asp