1985 300TD new bad engine sound at idle

[ScooterABC]

My 85 wagon (CA) is developing a new sound at idle. It's not nice. It is like a diesel engine rattle except louder. And it's getting worse. It's just fine when the throttle is down a little. But under 1000 rpm it sounds bad. Here's a little video clip. I'm hoping for an easy answer!
thanks
Scott

[whunter]

First, check your engine mounts.
It sounds like one has collapsed = allowing the aluminum arm to hammer against the engine mount cup.

Also check the bottom alternator bracket front ear is not broken.

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