�65 Corvette - cylinder wall stains - cause of higher oil consumption?

[Oliver S.]

One cylinder wall looks like this.
7DE5CB11-7FED-428B-A58A-7C92A36D5FD3.jpeg
The stains are not palpable and were caused by coolant mist condensing on the wall due to a hairline crack in one head (#6 cylinder) which is fixed now (new rebuilt heads). Can these stains be the sole reason for increased oil consumption (approx. 1/4 qt per 100mls - before and after head replacement)? The engine has 10.000 mls after a rebuild and there hadn’t been much oil consumption until 3 years ago (Oil level stayed in the upper range of the dipstick between the marks after 700mls). I’m torn between accepting it (I don’t drive that much) or have an engine rebuild - there are not many really knowledged rebuilders here in Germany - with respect to quality work on US V8 engines. I would appreciate your opinions.

Oliver

[Edward J.]

[Oliver S.]

DSC03488.jpg

The initial pic is from last year. Here is another pic where the left adjacent wall can be seen .. a bit. Respective spark plug was wet due to antifreeze/water. The other plug tips looked good and the other cylinder walls similar to the left in above picture.
Meanwhile, rebuilt numbers and date correct heads were installed, because:
There were no ridges or recessions palpable - using the finger tips (fingernails? I don't know)
The valves had too much play and for the new heads new valves were used. During disassembly of the old heads oil dripped from the guides when the valves were removed - this was considered to be the main cause of the increased oil consumption.

Oliver

[David M.]

[Oliver S.]

[Eric J.]

Start with the basics. Does it noticeably burn oil all the time? Meaning does the engine smoke? Does it smoke at startup? Is there oil in the coolant? 1 quart every 400 miles must be going somewhere. If it smokes all the time I suspect you may have a broken piston ring. If it smokes at startup valve seals. If there is oil in the coolant you may have a improperly installed head gasket.

Now if all of these are ruled out check the crank case ventilation. A clogged hose or PCV system or inoperative valve can increase oil consumption because pressure builds when the vapors in the crankcase aren't allowed to flow into the combustion chambers. That additional pressure can force oil past seals and gaskets

[Patrick H.]

https://www.onallcylinders.com/2016/04/08/ask-away-jeff-smith-whats-causing-excessive-oil-consumption-engine/

[Oliver S.]

[Oliver S.]