1. replace the whole tensioner. Take it apart and install the body into the block, then the piston, then the spring and cover.
2. Yes, the pins are replaceable. I have done this with mine.
3. You can chock the back of the chain with a hammer and peen the front with a ball peen hammer. You have to press the new link on though. Just use caution and a small socket with some large pliers and it will push on.
1991 GMC Syclone
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