Turns out, a proper LB7 injector cup removal/re-installation really isn't all that complicated. Shown above is the machined deck surface of an LB7 cylinder head illustrating the appearance of a properly installed injector cup(s). If you run your finger over the end of the cup, you'd just barely feel the end of the cup protruding above the deck surface. Only .004" was removed from the deck when this head was re-surfaced. While hard to see in this image, there was a barely visible ring of red Loc-Tite 272 around the end of the cup, indicating that the proper amount of sealant was uniformly applied and distributed as the cup was driven into the head. The Loc-Tite not only seals the cup once cured but also lubricates the end of the cup as it's inserted into the head. Can't install them without this sealant - they won't go in without the lubrication qualities of the sealant.
From the top side, you can see the correct position of the cups after being inserted into the heads. The video link in a previous post will show you how to properly insert each cup. For the sake of more info, the 2 large O-rings that seal the top (big end) of the cups in the head are lubricated before being inserted. I've heard of many different recommendations for a lubricant... ranging from liquid dish soap to coolant to engine oil to chassis grease. Now, these O-rings seal engine lubricant from reaching the engine coolant (or vice-versa), so from a practical standpoint, there are multiple correct answers as to which might be best. I chose to use a light coating of clean chassis grease, applied to both the O-rings and the inside of the top-side hole in the heads. The small-end of each hole should remain spotlessly clean and dry before receiving the Loc-Tite 272 sealant. It's been 4-1/2 years and nearly 20,000 miles since these photos were taken, without a hint of a coolant or oil leak. The above video link will show more detail.
Jim
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