Hello. Yes I'm a new member . Does anyone here rebuild travel motors? I want to rebuild myself and need advice. I have a koehring 6612 that has slow travel on one side that has been progressingly getting worse and now the other side is getting bad also, once the fluid warms up the one side is basically worthless. I have removed the case drain and there is significant fluid bypass. All other functions on machine work good. I am at the beginning stages of diagnosis and I know that it my be the rotary manifold and the linkage as well. Once I pull the motors and disassemble them what are the components that are usually worn that are causing the fluid bypass and the loss of force output of the motor, is it the entire rotating group with Pistons and the block? What are the most common parts that need looked at? It is a hy-dash travel motor. I have search the net far and wide for info and all I find is people showing messed up motors or wanting people to send them in for repair. This machine is kind of old and the only way I can afford to have it repaired is to attempt it myself.
I think that despite the possibility that your travel motors may well require rebuilding/replacement IMO you're going at the problem backwards. The first thing you should be rebuilding is the centre swivel, or rotary manifold as you refer to it. Unless the swivel is in tip-top order you're batting blind going into the travel motors.
Thanks for the reply. All of what you say is true, however I am looking for someone that knows how to rebuild this travel motors so that if it comes down to it I will be knowledgeable of the correct procedures and parts that need repaired or replaced. I have not checked pressures yet at the swivel manifold or the travel motors or switched the lines around yet to see if problem changes sides. I think that all the pipes are hard lines so if I wanted to swap them around I will have to get creative with hydrolic hoses and fittings.
Hy-Dash is not fun from what I hear, you might want to try H&R: http://www.hrparts.com/finaldrives.html
I've never dealt with H&R for rebuilt motors but they were our GO TO people for used Dresser and Hough parts over the years always seemed to be good people and I'm not saying that just because the CEO has the same last name as me, no relation!
I called that hrparts.com and all they want to do is sell me an entire drive. I know these things can but repaired, probably the people who can do it don't hang around on these forums. Not everyone with an excavator that messes up buys a new final for thousands of dollars or takes them out and sends them away to be repaired
Or more likely the Hy-Dash drives are obsolete and parts are not available. This is VERY common on drives, even if they're only a few years old. Just sayin'. Have you tried your Koehring dealer?
Problem is until one has the drive apart so each part can be inspected it would be impossible to even try to make a wild guess on what is wrong or how much it will cost. Plus as Nige says if you have leaks in the supply to the motor even a factory fresh motor is not going to function properly. This needs to be looked at as a system on not separate parts. I'm not familiar with this specific machine and don't know if the oil for the drive motors is supplied by the same pump as the oil for other functions. Problem could be the pump, the swivel, control valve or the motors or any combination of the above. Need to keep in mind that what ever caused wear/damage to one component also went through all the other sections of the system.
I have to agree with Nige . Unless the motor is running a serious temperature ,the swivel or distributer seals are the best place to start . If you do the work your self ,the seal kit wont break the bank and if the machine is 8 years + or has 8K hours + , they cant have much left in them IMO .
I have built several travel motors small and large. There's not a whole lot to them that can go wrong. Special tooling sometimes required to torque center nut. But have you compared case drains? Also, you can swap hoses on top side of swivel too? They're not bad to mess with as long as you pay attention to how you took it apart.
I ran a 366 Bantam for a few years that leaked 5 gallons a day from one of the travel motors,I called it my dust control.I think it was still leaking when I left for another job.Ron G
I've had them apart before and only remember the final drive side. From personal experience it was never worth trying to repair one of those final drive gear sets. As I recall you pull the motor and reduction gear from the machine as a set. Then you can set the unit up on the final drive end and remove the motor. I don't know just what model of Hi-Dash you have and I'm kind of surprised at hearing of a Koehring using one. I suspect you may have a clone made by someone else and given Koehring colors. I believe Koehring was bought out years ago and the likelihood of a dealer somewhere is pretty remote. The leakage on hydraulic motors is usually the result of wear and damage on the seal plate that contacts the end of the piston and barrel assembly. Many times all you have to do is lap them back in together to clean up the wear along with installing new bearings and seals. If the machine has had a catastrophic failure most of the machines I've had to work on ended up with a lot of the trash in the motors which required lots of parts and labor. As stated above you would generally troubleshoot from the cheapest most likely item working toward the more expensive things. In this case when you eliminate the cheap fixes you will likely have to make a decision on whether or not the machine is worth repairing at all. I suspect that is why you are asking about rebuilding the motors in the first place. Good Luck
Just a word of Warning here, Hy-Dash gear hubs are Timed up on the outer gear sets, that's the 3 gears that are hooked onto the little centre gear at the outer case end, the timing marks need to all point North as best as I can describe it, I can go into total detail on the Hy-Dash hubs but I don't know what a Koehring "Anything" looks like as we have none that I know of in the U.K. tctractors p.s. we call the seal plate the port plate, also have you done a case drain check on both motors?
Yes I am going to do pressure checks first and start at the swival manifold first. all the lines are hard lines not hoses so I can't just switch the hoses. I just want knowledge of the motors if I have to get that far into it. Tractor guy, john c, and tc tractors, thank you, this is some of the information I am looking for. My question in the first post was, I am looking for people who have taken apart and repaired travel motors.