I have an old 215 1984 model. Serial number 57Y01320. Replaced both the big hydro pumps 8J6848. They were both weak. 1 weaker than the other. Rebuild the swivel group but I’m still having travel problems. It has always been stronger going forward than backwards even before pumps rebuilt. After changing pumps it will go forward and pivot turn as it should. Reverse is slower with little engine bog but will only pivot turn with right track and when try to pivot with left track just stalls but don’t pull engine down much. So I took all hoses for drive motors case drains and brakes and swapped them from side to side to see if problem went with the swap. It did. Now it will travel strong in reverse pivot both turn both left and right. Forward is now weak and will pivot turn with the left track slowly but pivot with right track it stalls. If u are traveling forward and move the steer lever slightly to the right it speeds travel up a bit. If u move it slightly to the left it doesn’t have same effect. Any ideas on what’s going on? Track chains are also new.
Good day D809 From your thread it appears that the machine has had most of the major parts replaced, if I have followed the story correctly one side is down in one direction - switching the lines changed the status which indicates the issue is prior motor - central joint or a main valve issue - not sure if your shock /refill valves are located at the motor or main valve- main valve location could make these suspect.Suggest you appeal for a hydraulic schematic that will make trouble shooting much easier. Kind regards Uffex
Thought about trying to rebuild the steering valve but I’m ready to do a repair that fixes it instead of trial error.
Document regarding principles of System Operation and Testing & Adjusting for your machine hydraulic system are available. Drop me a PM and I'll gladly email them to you - don't forget to include your email address in the PM.......
First thing I would do is check case drain flowrate off each track motor. This will determine the condition of the motors so you are NOT chasing your tail. This is literally pump/motor 101. If you need help understanding what to do, ask or look up a video. After that I would verify the spool pilot pressure right at the main valve. There are test ports on each spool valve head and stupid simple to test with a gauge. If you are getting full pressure in both directions, report back. Honestly, I suspect either lazy motors, dragging brakes, or spools that are not moving far enough. The fact that the engine does not pull down leans towards either spools or motors are worn. Case drains help determine lots.
Can anyone tell me if the track brake valve is located behind the cab beside the boom vent valve? It’s piggy backed on the block best I can tell where u put the gauge to check pilot pressure.
Not really sure what you are trying to do but looking at pressure to the brakes is about the last thing I recommended. You need to look at pilot pressure ON the control valve heads. There are buckets over each valve spool, one on each side for each direction. There is a port on each bucket. There will be like 12 of them. It should be simple to look at pilot pressure in one direction (full pedal is what you need to use), vs the other direction on the opposite side of the spool. Once that is determined, other things will follow. I highly doubt a brake is dragging (but is on the table) just because the engine will typically bog and present a high load sound.
I checked the pilot pressure on the main valve this morning before I had to move to other things. Didn’t have much time to mess with it. Anyway pilot pressure on 1 was 240 at the and the other was 250 at the max. Book says screw the plunger in on brake valve to do some of the test and I don’t know which valve that is.
Not sure where the brake plunger is. Guess we will make an assumption the brakes don't leak? Have you checked the final's oil level? If over full, brakes are leaking. personally, with notable engine bog difference fwd/rev, I might look at other things. Reduced load usually means the oil is bypassing the load. Either from serious drive motor internal leakage (case drain test I noted) or a valve somewhere. I do believe those pedals were known to get wonky..... Possibly a rotary coupler issue as well. You can also swap the control hoses right to left to see if the problem chases the control circuit or stays with the drive motor.
It does leak out the vents on the brakes some. Has for a while but I thought I had other issues more serious. Now that I’ve addressed pumps I was thinking it possibly could have some brake drag. Especially since pilot pressure to main valve is down nearly 100 pounds. Says it needs at least 260 pounds to disengage brakes so at 240 250 I’m not getting enough pressure
I don't have your machine's books but IIRC, leaking out the vent means the motor can also be leaking and filling the cavity between them? Good idea to check oil on finals. That can only come from a leaking brake. Also, I seem to recall a target of about 300psi pilot pressure to the spools? I do agree that you should at least get your target pressure to disengage the brakes. by this time there is probably little left of them if they are dragging. What does it do with a track in the air and running it back and forth? If obviously slower in one direction, I would be chasing an oil flow issue.
Have you pulled the direction pedals off and checked for full stroke ? Have you pulled bottom plate under cab floor off and checked valve for full stroke ? From your results from changing hoses that would be the first place I would look. Good luck Bob
Well I rebuilt the brakes down at finals and found lots of issues in them but got all new seals and brake disk and that was most of my issue. Walks and steers really good now compared to before. I still have something going on in the direction control valve under the floorboard since I travel faster forward than reverse but I can live with that. We just use this machine around the farm. Thanks for all the replies and input.