I had a 7745, I think is the right model #. Great tractor, was rated at around 70 hp. It was 4wd, Cab and ac, this model had a three point lift on the front also with a PTO on the front too. I bought it in the mid 80's, so its been a while. If it is the same set as mine was, when not using the rear PTO you had to take PTO lever to off position and release the hand clutch handle back down like its in the run position. If not done this way you will be riding the throw out bearing all the time. Your pic looks like some thing has been doing a lot instead of momentary use to star and stop PTO, which usually is not done very often. Sometimes once to engage and you the tractor four or five hours. These were very well built tractors. Mine even had an on board engine driven air compressor for wagon brakes in the cezh market.