Two weeks ago I bought a Caterpillar E70B. It's my first excavator. Before the Cat, I have put over a 1000 hours on my Mahindra 6520 4WD with backhoe. Besides changing a couple of lines and loose linkages on the bucket, I don't have much to do, except TLC and changing fluids and filters. Today I found out why the two lines to the rotary (swivel) joint wore out early. The angle bracket that holds the joint in place has two sheared bolts, allowing the joint to pivot backwards and forwards. My question, can I pull the rotary joint out as a unit, or will I have to disassemble it to get the housing out to remove the sheared bolts? hugs, Brandi
I would at least attempt to remove them in place, I'm too lazy to undo all those lines and clean up all that oil
I might be able to remove the lines and 90 degree fittings, but it is still an awkward place to try to remove broken bolts. I was planning on doing that first, and trying to turn the joint about 90 degrees for better drill access. hugs, Brandi
If they weren't loctited they may just spin right out, have you tried a seal pick or a small sharp chisel to see if they'll turn?
Lantraxco, I'll give the small, sharp chisel a try. I just came in from looking under and at the joint. There is no room to drill at all installed. I can't look at the bolts directly, I have to use a mirror. The chisel or small pick idea is work trying before ripping out all the boom hard lines for access and all the joint lines............and all that fluid dripping on you while laying on the floor. hugs, Brandi
Oh yeah.........my printed parts manual and CD service manual arrived today. It says the joint weighs 42 pounds. Of course the manual says lift it in and out with a hoist. hugs, Brandi
Guess not many folks here have dealt with a E70B's rotary joint. I decided I had to remove it to get a drill on it, as I only had 4-5 inches of space after removing the 4 hoses to the joint. I removed the hoses and 90 degree fittings and standoffs. I then had enough space to see it had oil and dirt over the holes. I shoved a small pick in the holes to see how deep the broken bolt threads were. In both holes I went in about an inch. I then cleaned out the holes with alcohol and cotton swabs and started trying mm and fractional bolts. I had to run to the auto parts store for some 7mm bolts. The 7mm bolts0 screwed in tight. So..........I don't have to remove the joint.........and that's a good feeling. hugs, Brandi
:drinkup
Well, the M7 bolts had me fooled. One tightened up and one spun and spun. So I went to Lowes and bought a cheap 90 degree drill attachment, then an M8-1.25 tap at Northern Tool. My letter H drill bit walked right into the hole while I held the 90 degree attachment and my son, up on the engine deck, triggered the Makita drill. I then fed the tap in with a 1/4 ratchet and the tap went in and just cleaned out the threads on both holes. They were M8 after all. It blows me a way the dirt and oil could hold a M7 bolt tight in an M8 threaded hole. Anyway, it's all back together now. Later today I'll change the fluid and filters. hugs, Brandi
I'm surprised that you could find M7 bolts off the shelf. I wouldn't say it's obsolete, but definitely non-preferred.
Good job, that was a tight space
And even more surprising in a country that has never truly adopted the metric system ......... I would struggle to get M7 bolts here...!!
I ordered the bolts online last Tuesday early am. They came in Saturday's mail. I did find that M7 and 9/16th bolts are the scorn of industry. No one wants to use them. I found out about the 9/16th inch bolt when I went to load and bring the Cat home. The stick control acted like it was locked. I finally figured out someone used a 9/16th bolt as the pivot pin in the left controls. The bolt had a snap ring holding on at the last thread, with the majority of threads cut off. The bolt would vibrate forward and jam in the access hole in the control column. I couldn't find a new bolt and didn't wanna pay Cat prices for the correct pin and setscrews, so I cut the bolt shorter, drilled the end for a cotter pin, and reinstalled with the correct amount of shimming washers and cotter pinned it. hugs, Brandi
Thanks! That it was. hugs, Brandi