I noticed some strange things happening with my tractor and traced the problems back to the mounting bolts for the backhoe subframe. There are a total of 14 bolts holding this thing on (actually there are some more parts and more bolts but the main subframe has 14 bolts.) Five of the bolts had broken and the rest were loose. These are big bolts too - 16mm or 5/8" grade 8 bolts. I was able to get the broken ends of three of the bolts out of the tractor but I will have to use a torch to anneal the remaining two so I can drill for an easyout. I hate to think what damage would have occurred if I had not found this before I used the backhoe again. I had just replaced a couple of hoses and had a cylinder seal replaced and had made a repair of the boom transport pin socket. I was planning to take the unit out for a few hours of work when I noticed that the tractor gear range selector was hard to operate and that it would not go into the high range. One of the subframe brackets had shifted and was hitting the shift lever. The backhoe did not sag enough to notice when looking at it but it was sagging enough that the rockshaft pins barely caught in the lift points on the hoe.
The dealer installed the backhoe and I am sure that they did not pay any attention to torque specs when they did the installation. I say this because when I asked them about conflicting torque specs in JD documentation they said they did not use a torque wrench. I suspect that few mechanics use do this. I worked as a mechanic for a couple of months this summer and know that it is hard to take any extra time to do things right because people do not want to pay for labor. I am going to add lockwashers (JD apparently does not consider them necessary) and locktite as well as use a torque wrench when I put it back together.
</font><font color="blue" class="small">( Do "easyouts" work well?)</font>
In this case the answer is a resounding NO!
Since the bolts were metric grade 10.9, I would have had to anneal them. I tried to do this with an acetylene torch using the cutting torch to get more heat. The bolts were broken below the surface in the cast iron transmission housing and I could not get them hot enough to soften them. The heat and liberal doses of PB-Blaster loosened them enought that I was able to turn them to just above the surface using chisels and punches. The torch did soften the surface of the bolts just enough that the the punch could make tiny impressions to lever against. I spent about 8 hours getting three bolts out not counting the trips to get new tools. All this because the lousy mechanic at the dealer did not follow the instructions for installing the backhoe. He should have torqued the bolts to 190 ft-lb. I doubt he even tightened them to 100 ft-lb.
I wonder if any one else has had similar problems with a 47/48/49 backhoe. I had been having problems with the boom transport pin coming out while using the FEL with the backhoe attached. Since the whole backhoe was probably flopping around this may have contributed to the problem with the transport pin coming out. This caused another problem that I had to fix.
My 48 BH has a travel locking pin that has a detent on the end and a pull ring on the other. It's a little bit harder to get in, but once inserted, I've had no problem with it coming out -- the detent seems to hold it securely enough. Does your pin have a detent on the end?
</font><font color="blue" class="small">( Does your pin have a detent on the end? )</font>
Mine is the same as yours. I have been using the backhoe to dig and the FEL to move a very large amount of dirt. I would dig with the backhoe for an hour or two and then spend another couple of hours moving the dirt. Once the pin started coming out the welds on the spacer between the boom and frame broke and the problem kept getting worse to the point that the pin would bend and have to be straightened almost every day and I had to use a hammer to insert it and a hammer and punch to remove it. It would have been a pain to reweld the spacers so I removed them and bolted on some 4"x4"x1" spacer blocks that I made. I hope these will solve the problem. If not I will make a new pin and use a hitch pin to retain it. I have not been able to get any time on the BH since then as I have been busy making other repairs, i.e., replacing hoses and cylinder seals and fixing the subframe. I got it back together yesterday and immediately broke a valve stem off on a front wheel while clearing some brush.