When I first backed the green monster into my garage to cool off back in March of 2015 my heart sank when I noticed a huge puddle of oil rather quickly appear out of nowhere from the front of the engine. A few hours of wrenching later I’d discovered the cause. When the water pump bearing starts to wear out on these gen 2 LT-1s it sometimes destroys the drive shaft seal in the front of the timing cover.
Even though the picture is horribly out of focus, it would be difficult to describe how elated I was when I found this spot where the oil had washed the crud off the front of the timing cover.
The most difficult part of this job was devising a seal insertion tool to get the lips over the splined part of the drive shaft. Ultimately I used a piece of 3/8 soft copper and swelled it to fit. While I was there I went ahead and replaced the seal behind the optispark. Unfortunately it wouldn’t be the last time I had the optispark (and the water pump) off.
A word of wisdom to anyone working on one of these – replace the seals while you have the pump off. Even if it doesn’t appear damages or leaky, these things are reported to last not much more than 75,000 miles. It’s worth the extra hour of labor, even if you’re paying for it (the labor).