Hello all, first post. So I just purchased this today, it seems to be in fair condition. Except: It has some brake issues (no brakes at all). I was able to glean some info off of another post on here on the brake topic. I'm hoping to get some recommendations on parts suppliers to start looking into. The clutch cutout switch seems to do nothing, continued power to wheels when switched to left and brake is pressed. Also, can anyone provide any info off of the attached serial number. (#5501672) I am also open to any general thoughts, major concerns, or common gotchas with the 780. Much appreciated, Jess
Welcome JOlson! That's a nice looking hoe you've got and that loader bucket looks mean!
Welcome to HEF, Jess ! Your 780 was manufactured in 1976. Air is supplied to the valve with the lever from the RH brake pedal assembly. It not unusual for someone to remove the line from the brake valve and put a pipe plug in it. I did that on my own machine because the mechanical linkage would occasionally stick with the transmission in neutral. Then I would have to crawl underneath the tractor and put it back in gear. I now just put the shuttle shift lever in neutral when I want to raise the loader at a high speed. A link to the parts book is here ---> https://www.mycnhistore.com/us/en/c...ckhoe/cn/10D56496-EFBE-E111-9FCE-005056875BD6 If you have an eBay account, a service manual is available here---> https://www.ebay.com/itm/143056990124?hash=item214edc6fac:g:jLoAAOSw3v5YqCuv I have the service manual for your engine if you need it, I can make it available to you.
Thanks Tinkerer and aighead, It was delivered Thursday and I was able to play for a couple hours, it is a bit of an upgrade over my ford 3500!. Previous owner says that he had to keep adding brake fluid. I will take a look at master cylinders on down for leaks today. Thanks for the links on manuals and parts book!
Looks good Jess ! The info. that I gave you about the cut-out for the transmission may be incorrect. The 780CK'S can have either an air brake treadle valve or air assisted (fluid) master cylinders.
I was able to confirm actuation of the master cylinders when the treadle is pressed. The right was empty the left was full of brake fluid (I might have that backwards). Neither seem to slow wheel movement. I have A LOT of what I think is oil coming from the right wheel hub, coating the inside of that rim. I will have to wait for another hand to bleed the brakes. The parking brake seems to stop the drive line from being turned by hand, barely has an effect on stopping a slow roll. The parking brake drum behind the transmission is fairly well coated in oil as well. I might try adjusting it but I wouldn't be surprised if it was oil logged inside. It seems as though the air line for the clutch disconnect switch has been cut. When I activate that it just hisses air loudly. I haven't isolated where. I'll have to look at the manual which he did send his and I was able to get ahold of pdfs .
Welcome to the HEF! Glad She went to a good home. You’ll enjoy many hours of digging.