turbo chain tensioner failure?

[Orange71S]

Has anyone ever experienced a turbo chain tensioner failure?
When the engine in my '71 S was rebuilt in 1985, turbo tensioners were put in. Last month, the driver's side chain started making a horrible noise at idle only.
I didn't drive it, but took it to my mechanic and he verified the chain tensioner had collapsed. I thought this didn't happen.
Could it have aged poorly due to lack of use?
Any ideas are welcome.
Jay

[RSTarga]

Had an original tensioner failed my 73S at around 35,000m after sitting for a few months (1975). Put Turbo tensioners on a subsequent rebuild in 85 car was regularly driven and serviced, They were rebuilt in 1999, and ran them until putting pressure fed on in 2018.
Things leak when left sitting around. If they hadn't been serviced since 1985 even more so.
I feel for you because my 1975 failure required a complete rebuild.

[edmayo]

Have the tensioner rebuilt using 60 wt. oil, use the later wide bush idler arms (do the other side while you're at it) add tensioner guards, and you should be for another 38 years!

[Richy]

Follow ED's recommendation , the later style idler sprocket arms are as important as the Turbo tensioner update . The Turbo tensioners alone are a small improvement because of the larger reservoir , they need to be installed with the later arms ,

[Orange71S]

Thanks for commiserating, David. But, my mechanic and I are pretty sure there is no damage.
Good suggestion, Ed. I didn't know they could be rebuilt.
Jay