What does the condition of this spark plug tell me?

Geos7812

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I just changed the plugs in my 88 4.2 in anticipation of getting it smogged. This is what the plug looks like. I am thinking there shouldn’t be oil on the threads but not sure. Does this pic tell me anything or is this normal?
 
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Chief Hof

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Morning Geos...looks like the oil is on the wrench 'boss' portion of the plug as well, recommend checking your valve cover gasket ...oil could be migrating from there

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Geos7812

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Morning Geos...looks like the oil is on the wrench 'boss' portion of the plug as well, recommend checking your valve cover gasket ...oil could be migrating from there

View attachment 120329

Valve cover gasket has been replaced and looks to be in good shape. However, I do have a leak somewhere and bought a leak detection kit to help figure it out.

Regarding the plug, would you say that it was “ash fouled”?
 
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Geos7812

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Yes, somewhat carboned up. Hows the oil consumption?
I am not sure yet. I just bought it and wasn’t driving much. It came with dry rot tires and I didn’t trust them to go far. If I have oil consumption, does it mean that I am on my way to a rebuild? Jeep has 47K on the ODO, but who know how much idle time etc.

If on the way to a rebuild, what could I anticipate spending, ish?
 

Gilaguy23

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Oil consumption/disappearing can be from leaks, dry rotted valve stem seals, bad rings bla,bla,bla. How's the oil pressure idling when hot? I surely would not get too worked up over anything until you get to drive it and put some miles on it. If its new to you and you have no idea of its history Id start with a set of regular old champion copper plugs, a fresh oil change with something like Valvoline 10/30 conventional and a good filter and some fresh gas. Obviously make sure the cooling system is OK and its safe to drive ,brakes and that kinda stuff. We've had new F250 work trucks that burned a quart every 1000 miles and Ive owned far worst with regard to oil consumption. far as rebuilding it.... that way things are now with the labor and parts shortages who knows. I friend just took a 283 in for a rebuild to a shop in Albuq and he gonna pay $3500 for rebuild of mostly stock parts save a RV cam and higher comp pistons. Id guess a 258 would be close to the same as their pretty basic engines. Again, Id drive the thing a bunch and see where your at before getting to worried about a rebuild.
 
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Chief Hof

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There are some ash deposits forming, but I agree with Gilaguy...the plug you're currently running is a bit overkill. Biggest thing here is to start with manufacturer recommended tune-up items and settings, then drive it a while and recheck...when was the last time the plugs were changed?
 
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Geos7812

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There are some ash deposits forming, but I agree with Gilaguy...the plug you're currently running is a bit overkill. Biggest thing here is to start with manufacturer recommended tune-up items and settings, then drive it a while and recheck...when was the last time the plugs were changed?
Good stuff gents. Thanks. I have done the tune up stuff. I drove it +\- 70 miles today. Ran like a top 65-75 straight down the highway. I will check for oil consumption and also put it under a black light to looks for leaks. I added die to the oil. I definitely had oil hitting the ground but couldn’t tell if I was melting off old crud or if I actually have a leak. This is so fun!
 

T-Rex Jeepster

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Looks lean to me.....Could be altitude, High ethanol content, Does it have a carb? If so, Bigger jets with a rebuild....And I HIGHLY recommend using this in every tank of fuel for "Wetting" Up the fuel and giving upper cylinder lube....
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