Even though they are two different model MF tractors, I think there is is a high probability that my problem is also the idler gear based on the similarities of the noise. Mine is much louder when in neutral with the clutch engaged and is somewhat quieter when running along in gear.
I wonder if it is okay to run the tractor a little or should I park it immediately and tear it down. It sure is disappointing because the tractor has just over 500 hrs, has never been worked hard or abused and has been serviced according to the Operators Manual. In fact, the engine oil and filter gets changed every year even though we put less than 50 hrs a year on it.
Many thanks for your help.