On 19 Feb 2017, Thomas Aczel in Australia wrote:
"My newly and meticulously built engine started to make an increasingly loud whine from the front end of the engine within 1200 miles of being fitted. The motor still ran perfectly well. Removing the fan belt made no difference. The timing cover came off. We discovered that the rubber pad on the (brand new) Rolon timing chain tensioner had separated from the tensioner blade body".

"A subsequent search suggests the Rolon failure is moderately common".
www.mgexp.com/phorum/read.php?41,2502263 -- Regards, Tom

More failures reported by:
Austin Blanch in Raymond Terrace, Australia
Shaun Holmes in Norwich, Norfolk, UK
Basil Adams near Sears Point, CA, USA
Heath Racing in Tennessee, USA
Dick Russ in Oklahoma City, Oklahoma, USA
Scott Brown in Redwood City, California, USA
Hap Waldrop in Greenville, SC, USA
Eric Russell in Mebane, North Carolina, USA
Bruce Hopgood in Montreal, Quebec, Canada

On Mar 5, 2015, Eric Russell wrote:
"Attached is a photo of the failed tensioner. The rubber block is (was) only glued to the metal part".

There is a better part available where the rubber wraps around the plate and is vulcanized. Made in France, it is commonly listed as a Jaguar part, but it certainly fits lots of other engines. See Engine article CS-103A