Odd noise in a 7060

 Lets start this by saying I have never driven or even been around a 7000 series tractor before so please bear with me a bit. I will tell you as much as I know about the tractor.

Very early build date,  serial #1103 so 1974 model I think. Power director tranny.

Tractor started up with just a very small shot of starting fluid with junk batteries and cables. No leaks anywhere and it had not been cleaned up.

At idle in neutral there is a noise that can be heard best standing behind the tractor. I would descride it as a rattle. Push in the clutch and it stops. Raise the throttle and you can't hear it. The owner said it has always had this noise. He was having problems with the remotes and had someone charge him $1700 to rebuild the hydraulic pump. That didn't fix the issue and he had someone else take a look and make adjustment and no more issues. He says the rattle got louder after the pump work.

Tranny shifts fine and feels tight, no slop in the shifter. No grinding, ranges and high/low buttons work.

The tach is broken at 1900 hrs but was working at one time. Present owner says he put maybe 500 hours on it the the last five years but who knows.

Present owner was pulling a 8 yard dirt pan with it but wants to put money into a 1086 International that he has to replace this tractor.

Anyone have an opinion on this noise?