Oil Sludge
This is fairly common , old sludge from cheapo paraffin based Motor Oils .
It's why it's so important to always do
HOT oil changes , so the sludge is warmed up and circulating , some of it will drain out with the old oil .
One or two synthetic
hot oil changes would have cleaned this crud out too .
No worries , just keep working diligently and scrape lose as much of that gooey crud as you can , I find most Thrift Stores have scads of clean towels that are too raggedy to sell , offer the Mgr. $5 the pound for cleaned rags and try not to accept nylon or polyester as they don't absorb much .
I go through more rags that you can imagine but the junk I own and rely upon , is always full of this crud whenI buy it so I take the time to wipe it up & out and in a couple thousand miles , the engine is squeaky clean inside , no matter how worn out and clanky it may be .
It's nearly sunup , did you alls remember to set your clocks ahead one hour ? .
I'm shortly off to scrape clean my badly oil fouled spark plugs , again
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I gotta have this head re built with new silicone bronze valve guides , stellite seats and one piece stailness steel valves if I can find 'em .
God head work begins @ $500.00 and zooms up from there , I may have found a local guy who knows how to unshroud the valve guide bosses and polish the exhaust ports for improved flow , increasing power and fuel economy whilst reducing the engine's heat at the same time...
Imagine ! a $2,000 cylinder head on a $800.00 truck
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Hey , this worked out very well indeed on my old Metropolitan Nash
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