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Why Are the Left and Right Bank Spark Plug Tubes Different?
While installing new spark plugs, I noticed a significant difference between the left bank and right bank spark plug tubes. The left bank tubes (closest to the radiator) appear to be longer than right bank tubes.
The first image shows an approximate 3 mm gap between the top of the tube and the rocker cover in the left bank. The second image shows an approximate 15 mm gap between the top of the tube and the rocker cover in the right bank. Is this by design? Why?
The right bank has engine oil pooling above the tube seal about 1 mm deep. Does this indicate a pending leak that will eventually fill the spark plug tube with oil? Looking at the engine manual, there are baffles in both rocker covers that should allow for oil drain back. I'm surprised a gap exists between the spark plug tube and rocker cover. I've never taken the rocker covers off. It appears the ignition coils help seal the crankcase?
It's supposed to seal around the tube. If it didn't, you have a blow by leak and oil in the tube. The coil has a seal so dirt doesn't get in from the outside, not to seal oil.
