Yes, that is it!! The guys that bought it must have fixed the injector pump. The guy that owns the business is a retired tractor mechanic with around 40 years experience. He said he could rebuild the injector pump fairly easily. I was hoping they would repaint it and all, but I guess the cosmetics were good enough. It is a nice tractor and I enjoyed it for 12 years, but the MF240 is really nice too.
I figured if I had the injector pump rebuild or replaced, it would cost me about $1200 parts labor. That would put me at $3,600 ($1,200 + the $2,400 trade in value) and not leave too much room from the $4,000 I thought the tractor was worth in the overall good condition that it is in. So the trade was worth it to me.
They also have it on eBay:
MASSEY FERUGSON 35 DELUXE TRACTOR DIESEL ENGINE - eBay (item 160433961331 end time Jun-11-10 04:13:01 PDT)