Case 480B Clutch Problem

[jcspeedy]

I have a 1977 Case 480B that I can not get into gear. The high/low will go into gear fine and the 1-4 gears will go into gear fine. When I try to put the shuttle shift into FORWARD or REVERSE, the gears just grind. It will not go into forward or reverse. Also, I can get the shuttle shift to go into gear and the high/low to go into gear, but it grinds when trying to put into 1-4 gears. Any suggestions?

 

[Jim.ME]

Some history may help. Has it been setting for an extended time, has it been operating but getting harder to get into gear over time, or did this happen suddenly? If it has been setting the clutch disc could be stuck to the flywheel or pressure plate. If it has been getting worse over time or happened suddenly you are likely looking at splitting it and doing a clutch job. A stuck clutch disc might break free.

Assuming this is a typical mechanical dry clutch. How is the clutch adjustment? You should have about 1-1/2" free play I believe from info I have. Free play may feel right even if the clutch disc is stuck. If that doesn't work a split is in order. Just my thoughts.

Is it out in the open where you can safely start it in gear? If so try it in a high gear and see if the tractor stops moving when you push the clutch. If not the clutch disc is stuck or there has been a failure in the pressure plate and or clutch disc. If it is stuck driving it around while holding the clutch pedal down and hitting the brakes repeatedly may break the disc free.

 

[jcspeedy]

Thanks for the reply. The backhoe is used weekly on my farm. It was used one day for about 2 hours and it slowly started having trouble gong into forward and reverse. The next day when I went to use it, it would grind when trying to put it into forward and reverse. I was able to "force" it into reverse once but have never been able to "force" it into forward. The tractor will not start unless the 1-4 gearshift is in neutral. It has always been that way since I have owned it (about 5 years). I can put it into neutral and it will start. After it is started, the 1-4 gears will not go into gear. The high/low and shuttle shift can both be in gear to start it (even now) but it will not go into gears 1-4. It grinds the same way that the shuttle shift grinds when trying to put it into forward/reverse. As far as the clutch pedal goes, it is where it is supposed to be. In summary, of the 3 gear shifts needed to make it operate (high/low, 1-4 and forward/reverse) only 2 of those will go into gear when it is started. Any of the 2 will go into gear, but the 3rd one grinds when trying to put it into gear. I hope this is helpful.

 

[Jim.ME]

(quoted from post at 11:21:52 06/27/20) Thanks for the reply. The backhoe is used weekly on my farm. It was used one day for about 2 hours and it slowly started having trouble gong into forward and reverse. The next day when I went to use it, it would grind when trying to put it into forward and reverse. I was able to "force" it into reverse once but have never been able to "force" it into forward. The tractor will not start unless the 1-4 gearshift is in neutral. It has always been that way since I have owned it (about 5 years). I can put it into neutral and it will start. After it is started, the 1-4 gears will not go into gear. The high/low and shuttle shift can both be in gear to start it (even now) but it will not go into gears 1-4. It grinds the same way that the shuttle shift grinds when trying to put it into forward/reverse. As far as the clutch pedal goes, it is where it is supposed to be. In summary, of the 3 gear shifts needed to make it operate (high/low, 1-4 and forward/reverse) only 2 of those will go into gear when it is started. Any of the 2 will go into gear, but the 3rd one grinds when trying to put it into gear. I hope this is helpful.

You would need to jumper out the neutral start safety switch to start it in gear. That said, if it was being used weekly I would not expect the clutch disc to be stuck. My thoughts are unless the clutch linkage has slipped badly, you will need to split it and do a clutch job.

 

[jcspeedy]

I was afraid that might be the situation but was hoping for an easier outcome. Thanks for your feedback

 

[old barney]

[ My 480B CK had a froze clutch I found the clevis eye holes wallered out on the ends of both clutch rods one at top of the first rod and at the adjustment clevis last rod on the bell housing rod. I replaced both clevis and adjusted it up so the clutch would disengage. But my tractor sat a few years under water in a swamp I think. The 480B-CK was a gift to me (or a curse) 5 years ago. I had been working on it for two years. Then had to take a year off healing a broken Femur. I finally got it home from 2 miles away in February. Three weeks ago I got it running first time in I think 15 years. Even though I had replaced the clevis's my clutch wouldn't let loose.
I believe you need to adjust the lower clevis. Simple operation: two person operation!!! one on pedal other under.
loosen the jam nut behind the clevis, remove the pin from the clevis and tighten the clevis on the rod a couple full turns, stick the pin back through the eye, test to see if clutch works now. Your clutch was working a couple weeks ago so I believe you just need to adjust the clevis a turn or two.

 

[jcspeedy]

Thank you very much for the reply and suggestion. I tried adjusting the clutch pedal by adjusting the clevis as you suggested. The clevis was already adjusted as tight as it would go and still attach to the pedal. I also tried loosening the clevis which made the rod longer and that didnt work either. Still hoping it is a simple fix so I dont have to break it apart and replace the clutch.