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Old 06-28-2012, 09:40 PM
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Originally Posted by lt1silverhawk View Post
I'd say the passenger-side seems to have more fouling/deposits.
In this case I'm talking about the individual plugs. Like we talked about earlier, where the idea was to try to tell if an exhaust or intake valve guide/seal was responsible for the oil getting into the chambers. An example (rather extreme, but shows what I mean) is:

It's obvious that the deposits are coming from whatever valve the encrusted side is facing. If the plug is marked for position, you will know if it was the exhaust or intake, although it's almost a moot point; at this juncture the only mechanical fix short of rebuilding the heads is to replace the valve stem seals to see if it helps.

I don't remember if you've used Seafoam or not but using Seafoam isn't just "pour it in and you're done". It can cause some crap to be on the plugs if the engine isn't "blown out" by some hard driving. There's a run down of how to go about it here, same place I found the plug photo.

I want to get an opinion: I am thinking of cleaning these plugs off thoroughly and using them one last time just to see where the oil/deposits end up. Or do they look just too far gone?
You can go ahead and clean them off real good. I'd suggest using carb spray and a wire brush.

BTW, the gap looked to be wide on a few of them and a couple had the ground strap tilted up (worst one below); you'd want the gap to be around 0.040" w/the ground strap as close to parallel to the bottom of the plug as possible.

It's better to get the right plug gap from the get-go, than trying to bend the ground strap of a platinum plug IMHO. On some plug brands that means ordering up the right part number to get the gap needed. Anywhere from 0.035" to 0.040" will be OK.

If all the engine has seen is just idling in the driveway and putt-putting around the neighborhood, the plugs are going to look a lot worst than if you were driving normally, i.e. for an extended time at full operating temps at normal highway speeds.
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