Thanks. I also found an article about 70's and 80's Ampex 456 tape that talked about a problem with the composition that causes it to absorb moisture over time, which makes it sticky.I'm not qualified to start doing maintenance on the deck, so as long as it works with the newer tape, I'll probably leave it as it is. If I have to take it to the shop, I'll pass on your message to the tech.
Thanks fo your help.