hi every1 hubby pulling hair out, ain't got much, lol we hav takin over manager of a property & there is a bulldozer here that has JD850 written on the side but we found a plate on the side that reads 850E S/N 357166T we think bit hard 2 read, hav look at pics of different bulldozer JD 850 & 850E but none look like what we got but apparently john deere doesn't make a 850E only CASE does, we hav been tryin 2 get a manuel 4 it but don't know which 1 2 get, please can any1 help as hubby need 2 fix track adjuster nipple & doesn't know how 2 pull apart as he think it need a new seal or something as it is not holding grease
Hi , a JD 850 sounds like its a fair size John Deere dozer , close to a D5 cat . If the 850 is like most dozers , in order to install new seals in the track adjuster he has to break the track and slide out the front idler . Not sure if the grease cylinder is on top of the side frame or in the frame like an excavator . he stall has to break the track and remove idle in order to get the adjusting rod out of the cylinder . Some seals are installed in the cylinder and other models the seals are on the shaft . Hope this helps .
A picture is worth a 1000 words. Put up pics of the dozer on a photo-hosting site such as Flickr, Photobucket, etc - then put the link to the photos in your next post. If it has a JD850 decal on the side, why would anyone try to make out it's a JD, when it's a Case? JD most certainly did build an 850E, your S/N shows it's a JD850 built in late 1980. It's not a Case 850E - the S/N of the Case 850E is typically "JJG0338322" or "JAK0217845" - i.e., 3 letters followed by 6 numbers starting with a zero. JD produced the 850 model, then followed it with the 850B, 850C, 850J and now the 850K. The JD dozers came with a standard length track frame and a long track frame, as did many makes of dozers. I think you'll find that when the JD850 was a current model around the early 1980's, the long track frame model was called the 850E ("E" for extended track frame). I'm pretty sure the long track frame JD850 tractor was still just a JD850 on the decals, but the S/N tag stated 850E, to ID the tractor as a long track model. Later, when the improved JD850B, JD 850C and JD850J models appeared, the long track version was called the JD850B LT, JD850C LT and JD850J LT. When the JD850K appeared, the long track version is called the JD850K XL. Confusing huh? Yep, sure is - and add in some JD excavator models with JD850D nomenclature as well, and you have a nightmare. This is what your tractor most likely looks like. You'll need manuals for the first of the JD850 model tractor, which was produced from 1980 to 1985. http://auction.repocast.com/details.cfm?ID=140525#photos To repair the track adjuster usually requires the track to be separated and the front idler rolled out to gain access to the track adjuster mechanism. Track adjusters usually fail because the seal that is supposed to hold the grease under pressure fails. You can buy a seal kit to repair the adjuster, but you have to ensure the track adjuster chromed piston is not in need of replacement, too - because if the chromed piston is damaged, the new seal kit won't last.