G,day i have a 312b 1998 import with 6500hrs machine is ' sweet as apple pie!' but the final drives slow up heaps when the machine warms up ! we only use the machine on the farm but would like to fix problem if we can any advise would be great cheers
Drive the machine in a circle and if after two or three circles it stops and will only travel straight it's likely a leaking swivel. Later Bob
312b cheers Bob I forgot to mention that the motor sounds like its labouring heavily when the machine slows down . I dont know if this info helps any
Well check the drive motors for ground up metal. There should be a case drain filter, change and cut open. Any motor problem should fill it with metal. Later Bob
Hey Bob can you please tell me where the adjustable main valve is for the track motors? cheers
The travel usually uses the same main relief as the implements and is raised when the travel is activated. There should be a couple on line/port relief valves on each motor but they are likely fine unless you have a problem with just one motor. Compare an implement stalled out to the pressure you get when travel will not move. "Gets worse when warm" means a leak some place, the swivel is more likely than a motor. If you have gauges and plugs, check pressures with the lines hooked up to the motors and then with the lines to the motors disconnected and plugged below the swivel. Move up to before the swivel with the plugs and repeat test. You will find the problem when the pressure reading improves. Later Bob
KTM, When the machine warms up, is the travel the only function that is slow and loads the engine, or do other functions have the same or similiar symptoms?
Thanks mate yeah its actually getting worse it doesnt even need to be hot! Ive done everyting. I would love to know what it is! Its only the tracks, is there any way to test swivel seal? any advice appreciated cheers
Test the motor/swivel problem as I posted above. Complete circuit, then with motors out and then swivel out. You will find the problem,likely a swivel. Later Bob
Thanks Bob Any tips on trying to find a service/workshop Manual for this machine The local CAT guys cant get me one because Its an import 312B
I bet they can find you parts though. What's your serial#? Later Bob
I would rebuild the swivel joint first , its much cheaper then a final drive motor or a pump rebuild . I would say that the O rings have dried out and are by passing fluid. When a drive starts to fail it will not track strait or counter steer and turn in a circle.
Hi KTM, wouldnt it be nice if someone posted a link to the service manual !!!!! I have a 1994 - 312 that i just purchased - seller had no manuals at all ... Im lost too!!
Mark, I have found many times the first sign of a leaking swivel is a machine that will not turn in a circle. Cat travel spools are float center, both ports are open to tank in hold. If you are just traveling with one track and the swivel leaks it will leak into a line that is open to tank. While traveling straight it might leak into a pressurized line. Later Bob
You can tell by how it stalls the track. counter rotate normally stalls one track. I usually pull the FD covers and put 4 pressure taps in the motor and monitor the pressures. You will see low pressures, pressures when there shouldn't be any etc. A high hour machine with no history of a previous repair, resealing the swivel is the normal fix.
Hey guys thanx for this Serial#9HR 1-up Cheers
Hi guys Is it a difficult job to replace the swivel Seals Cant seem to locate a service manual Cheers
You would be best to remove and install the swivel yourself and have the dealer or a local shop reseal it. It might be a bit trickey pushing it back together with new seals so if one gets dammaged it can be on them not you. They should have more tools to work with. I couldn't get anything on your serial# machine either. Later Bob
Resealing the swivel is simple. Disconnect and mark the hoses and fittings on the bottom, remove the mounting bolts and put a reference mark. On top remove the hoses and bolts in the rubber seal. lift it out. To disassemble, remove the plate on the botton and then retainer plate under that. The two will now pull apart. I put one in the vise and lift off the other with the crane while tapping it so it doesnt bind. Install new o-rings and seals, lube up and carefully assemble. I use a deadblow to knock it together. This can be trickey so make sure you use enough lube. Your machine is a ISJ so use one of these serial numbers.
This is what it looks like.
Thanks For all the help guys! should be able to sort the problem now may the earth moving gods shine on you all!
Hello ktm350exc, I have a similar problem with my 312b about a 1998 model like yours, i was browsing the net for help and i stumble here with you guys. Any info to fix will be one step in trying. Mine is slow when first started and almost dead when hot. I have already replace the swivel seals. mcpherson
hey guys I have a similar problem on my 312b serial # similar to ktm350, please give me some possible tips what i can do to fix final drive slow to almost stop. mcpherson