B204 (2.0 liter, 4-cylinder 16-valve) engine at 100k miles after oil
changes with conventional oil every 3-5k miles and after treatment with
a quick (20-min) engine oil flush. Compression and leak-down tests
show moderate engine wear. An oil test (Used Oil Analysis) performed
by Blackstone Labs shows high lead and just over 2% fuel in the oil, but
no coolant or any other abnormal metals.
Valve cover removed for inspection. Click any pic below for a larger
image. |
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Valve Cover
Inside of valve cover, covered with baked-on oil deposits. For
details of valve cover removal and gasket replacement, see Valve
Cover. |
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Engine
Top of the engine after valve cover removal, timing chain and sprockets
on the left. Picture shows moderate to heavy tar-like oil deposits.
For more details and pics, see Sludge.
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Timing Chain and Sprockets
Light areas show normal discoloration. Dark areas are layers
of accumulated oil deposits. The timing chain was too covered with
oil deposits to inspect properly, but there were no obvious signs of wear
on the sprockets. For more information on the timing chain, see Timing
Chain Tensioner. |
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Timing Chain Gear
Close up showing a section of timing chain on one sprocket. View
shows difference between light areas (varnish), and dark areas covered
with oil deposits (sludge). |
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Cleaning
Valve cover, after a chemical wash. Oil deposits were removed fairly
easily in a parts washer, but the engine cannot be cleaned as easily. |
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