My brother and I are looking at a 2001 John Deere 160 LC to buy but it has some broken bolts that attach the slew bearing (I think some call it the rotec) to the upper works (house) on the back of the ring. Replacing the bolts doesn't appear to be a big deal but we are concerned about the underlying cause. Has anyone run across this problem?
Are you sure the bolts are broken? Not all the holes in the rotec bearing have bolts in them. If I remember correctly,the missing ones are usually under the cab, then there are 2 you will see from the rear and 1 on the right side.On a 160 LC there should be 40 bolts total. I will try and check the service manual and can send you a pattern if necessary.
bolts This doesnt answer your question, but this answer may help someone, with bolt removal. This was about 8 years ago, I had an older excavator and I noticed, a few bolts broken off in the rotec/slew bearing flange. I could just picture, drilling and tapping and I never had been good at that. I think these were 5/8 or 3/4" bolts. I called an old friend of mine, his profession was welder. It takes a lot to impress me, but the way he got those bolts out, really impressed me. He took a 1/4" pipe nipple, about 3" long, he took the nipple and put it in the hole, where the bolt/stud was broken off. It was broken off about 1" down, in the threaded area. He then took his welder, and put the welding rod down inside the pipe nipple, thus welding the nipple to the broken bolt and not messing the threads in the bolt area. He then took a pair of pliers and screwed the nipple and broken bolt out of the hole. He did this with all the broken bolts. I really dont know if this would work, if the bolt was seized, or had loctite used. I have used this same process, several times since then. I know some of you out there are thinking, boy it doesnt take much to impress him, all I could think of was hours and hours of drilling and tapping. I think in 4-5 hours, we had the bolts out and the new ones back in and the seat, etc back in. Hope this helps someone.
My experience has always been that if there are broken rotex bolts, the bearing is shot, or close to it. The bolts get broken by movement in the bearing, and the movement is caused by wear and/or a faulty bearing. If in fact the bolts are broken, I would personally stay away from it unless you want to replace the bearing.
I have seen the same thing done with broken bolts on bottom rollers, and they are usually pretty tough to get out.
Knucklehaed, Alco, Willis- Thanks for the responses. The tip on removing the bolts could be very helpful if we get to that point. We were told that we should be able to probe the holes to determine if the bolts were ever in the holes but that seems like a less sure method than knowing which ones belong there. If someone is willing to email me a diagram of the bolt location I would really appreciate it. [email protected] . We are concerned about the bearing being worn to the point of needing repalcement. We think that could add $10K to the price of the maching even if we do the replacement ourselves. The machine has an added 1500 lbs on counter weight and has be used on a concrete breaker which has us concerned. Any other thoughts on this will be appreciated.
IT CAME FROM THE FACTORY WITH MISSING BOLTS I agree 100% our hitachi and other deere excavators are the same. I thought they had broken bolts also until I looked in the parts book to order the bolts and realized I had exactly the same amount of bolts in the bottom as the parts book said .I checked other hitachi and deere machines and found the same thing....I would bet a large amount of money they are not broke at all.....they just are not there....and that is how it was manufactured...
hey Karl,,,,,, did you read my response to your question