I was wondering if someone could tell me how to replace my pinion shaft and gear. Can I work through the top of the transmission and and shuttle housing covers or do I have to split the taackor apart in my 580B? I have already removed the crown gear and realize that the pinion needs to be pulled out through the differential housing, but how do I get at the other end of the of the pinion shaft to remove the nut holding it in place? John
John, I'm believe you will have to split the tractor to get the pinion shaft out. You are undertaking a big, big,big job here, but it looks like you are halfway down the runway(committed). Some good news out of all of this, is that if you have a converter drive model, you can do some preventative maintenance on the shuttle drive, while apart. The crown/pinion set-up is time consuming in itself. I think I have a picture of the cover over the front of the pinion shaft. In the picture you can just see one of 2 hydraulic jacks, and the blocking just behind. The loader bucket is up high, with angle iron braces on the loader cylinder rods, and the hoe bucket is(must be) down on the floor, in this picture. The steering column is hoisted up (1"), from the top of the cab.The jacks are used to help remove the 4 bolts that hold the front loader frames, to the radiator support; and keep the mating surfaces(torque tube& transaxle housing) parallel to each other(on removal/assembly). Phil
Thanks Phil. I was expecting that would be the case. What is your opinion on leaving the pinion and changing the crown gear if the pinion looks okay. John
Well it's been done before, mismatching crown and pinion gears, often with good results. I think poor step-up is a more common cause of premature failure. The pinion shaft should not have any end-play and preferably a slight preload on it's bearings. Carrier bearing preload is hard to set with the pinion in place, unless the crown gear has been removed. Getting the correct backlash and mesh pattern is also important. Carrier thrust washers have an updated # also. Do you have a service manual? Phil
Thanks Phil. I know I left my last question farely open. I try to do the best job I can, with as much forethought as my experience allows but sometimes it just doesn't make economic sence to go beyond a certain point, and sometimes it is plane stupidity not to repair certain things if you have every tore apart already. With that said you answered my question very well. I do have a sevice manual. I don't have a shop big enough for the hoe, so this is an outside job. I don't have any experience setting up differiencials, but I do have mechanical experience. I run a diesel electric generating station for our communitee, I have farming equipment and an assortment of Case backhoes. My first backhoe was a Case three point hitch hoe that I attached to my ** 35 tractor ( witch was undersized for the hoe). I was told that it was one of the first built by Case. When summer comes and the snow disappears, I will post a pictures of my three generations of backhoes. I hope that someone looking can help identify my oldest one a little better. Then I bought this 580B and now I also have a 580SL. When removing the crown gear I did take note of the slop - 1/8" end play between the crown and the pinion gears It is easy to critisize the last mechanic for the poor job, but I just hope that I can do better. I also know that I haven't had any brakes because they were saturated with gear lub. With no brakes you use the shuttle more than you should and hence the crown gear was stressed. There were two teeth missing on the crown gear when I pulled it out. Any more tips will be apprecieated. John
The slop in the carrier is most likely failed thrust washers. They wear out or break, then fall out. Early washers were fiber and eventually failed, updated ones are steel. I think the 580C had the updated washers. Roading a machine alot will wear the washers and the carrier bearings on all the Case backhoes with this transaxle design. When the carrier is able to move sideways under load and move away from the pinion, then the wear begins. Once the carrier is loose, then the oil seals in each bearing housing start leaking, ruining the brake linings. I'm surprised your pinion is okay. If you go ahead with replacing the crown gear and leaving the original pinion in place, let me know. Got to go, bedtime. Phil
At this point I am leaning towards using the original pinion as it is. I did have some advise earlier from an old timer mechanic that comes up here to repair some of my units at work. He also suggested that I could get away with it and is a 580B owner. I think I will wait to decide until I can have someone look at the pinion gear that has more experience than I. I did measure the thickness of the my metal thrust washer. One was .042 and the other was .034 inches thick. I am not sure what the original thickness was. It sounds like I should be replacing these washers in any case. I actually wasn't on to that one. John
As I recall there are 2 thrust washers on each side and various thicknesses available, and a proper orientation. I believe this determines side(spyder) gear backlash. Easy to set with the carrier out. I will have to check up on this. Also check your compartment floor for bits and pieces of washer. Also still trying to recall, it's 4 in the morning here . Each pinion and crown is matched for a reason. The depth that the pinion engages the crown(too close or too far away) is important, dimensionally, to get proper tooth contact. There is usually a number etched in the face of the pinion gear, so if you replace a -.005"pinion with a +.003" pinion, without changing the shim behind the pinion gear, you will probably have to go back and do it anyway. This is because no matter how much you move the carrier left or right(within the backlash spec), by switching the shims behind the bearing holders from side to side, tooth contact pattern won't be acceptable. If a +.003"pinion is replaced with the same one, by chance, it's not a guarantee of acceptable tooth contact either, but it should be very close. That is one of the risks you take by putting a different crown in place of the original, and not resetting pinion depth to what it should be(which is an unknown without a match). Tooth contact may not be within the ideal range, for long life. The other risk is using gears with wear on the teeth. Your worn pinion on a new or worn crown. Like putting in a new camshaft with worn lifters, maybe not quite that bad. I have not worked on very many differentials, but common sense applies. Basically one wants a specified preload on both the carrier and pinion shaft bearings; with the pinion at it's proper depth, and a specified backlash between the teeth, to give a favorable contact pattern. Phil
Forgot the picture