I recently bought a case 450 and have problems with the transmission. on the left side where the 4 bolts that hold the transmission to the frame, the threads are worn/stripped out and won't hold well. on the right side the frame broke down through the front bolts. the right side had been welded before but is now broke again. would I be able to weld it again and maybe add a plate over the weld? any help here would be great! should the crossbar before the transmission be tight to it or should there be play there? this dozer has the ROPs base. thanks
Welcome to HEF cowrider! Firstly, the bolts on LHS that come loose, is it possible to fit sightly longer bolts with loctite? For the best results the threads will need to be repaired using helecoils or inserts & the transmission will probably have to come out to do that & the holes in the chassis be welded & redrilled if they are wallowed out. About the crack on RHS, a plate to strengthen the repair is mandatory. The crossbar should be fixed tight, with no movement - where exactly is the problem? Sounds like you have a job on your hands!
Hi, thanks for the reply. the CLAMP, final drive to crossbar, has a gap between it and the bar. I haven't checked the other clamp to the frame to see if it has a gap yet. I was thinking that if there is play at the bar then it would work against the bolts in the transmission. I will work on that after I weld up the frame. thanks
Hi Cowrider, The clamp on the final drive to crossbar should have spacers in to take make sure that there is no play between the final drive housing and the crossbar. One of the problems that quite often occurs with the 450 is the track frame mounting bolts coming loose and allowing the frame to move about whilst the machine is working. This can cause problems with the transmission as the movement of the track frame can over time loosen the mounting bolts causing the problem you have described. Of course this can be prevented by checking the track frame mounting bolts regularly and tightening them if required. The repair methods Alrman mentions will help to cure the problem but you must remember to check the tightness of all the track frame mounting bolts regularly to prevent problems in the future. I have a service manual for your machine if you need one. It has been converted to PDF format so could be sent by email. Let me know if you are interested. Regards Terry
Thanks for the update. There was a large gap in both clamps on the crossbar. I removed the caps and ground down the flats to take out the gap. This took out the play from the finals. I repaired the frame by welding and adding a plate. On the side with the stripped out treads I ran a tap through to clean up what was left and used thread lock. So far it is working. I keep a eye on it and try not to work it hard. After I was pushing gravel in the creek and all was well. I got up onto the bank and noticed my right track running away. The bolts in the master had broken and separated. Never a dull moment. At least I was out of the water.