Hi guys, I just bought a 1990 ex150 with some issues and i have questions. So when im tracking I noticed that the right side track has barely any power compared to the left side which feels normal, cold or hot. Next problem is my swing motor oil leaks into the swing bearing area, does anyone know which seal needs replacing and if i can change it myself without any special tools? The pump whines even when its full of oil, it doesnt affect the performance of the machine, its just annoying to listen to it all day. Is there a hydraulic filter that might be plugged up? And last question is the 3 green lights on the dash, what do they mean? Thanks guys much appreciate any help.
Ive noticed the hitahi ex machines have dash 1 2 3 etc. How do i know which one mine is? The plate on the cab just says ex150.
Howdy! 1990 should be a dash 1 machine. Are you referring to the 3 green LEDs below the hour meter? Left is auto-idle on, centre is turtle travel speed, right is rabbit travel speed. Does the machine mistrack on level ground? Could be anything from track tension too tight, siezed rollers, binding final drive, propel brake not releasing fully, worn propel motor or leaking counter balance valves, leaking rotary manifold, pilot issues etc. Need more info to even guess I've never worked on a 150, Does this machine only have one pump like a 120? As far as the pump whine, is your oil foaming? Check for suction leaks, there is a mesh suction screen inside the tank, you can access it through the tank fill cover, I recommend draining the tank before removing the screen as any debris down there will go directly into the suction piping. Have you changed the return filter? If not or you have the old one, cut it open and look for brass, it could be from your pump or the lazy travel motor. I'm guessing your pump is just getting long in the tooth. Is it gear oil leaking from the swing bearing or hyd oil? If gear oil it's the swing drive pinion seal, no special tools required, the seal slips over the pinion gear. On my 790D same as dash 1 EX220 the snap ring on the pinion gear broke and took out the seal, If the pinion bearing is loose and causing the seal to leak it will require a 50ton press to re&re the bearing. Hope some of this helps! Greg
Thanks Greg! I'll be working on it this weekend. I bought a rotary manifold seal kit and the big seal for the swing device gear that I'll be changing. I'll update after the weekend
Changed the swing device seal over the weekend. I thought it would be a big job but it was actually quite simple. The seal on the bottom is held by a ring and bolts that comes right off and wholla. I used a harbor freight 1" air impact to unscrew the main bolts holding the swing device. Used my buddy's old school wrecker to pull the unit out. Powers washed it and changed the seal. Putting it back in was a little tricky but not too bad. I'd do this job over any transmission or clutch job any day.
3 green lights... the ones that come on when you depress the button below them... oil, coolant, hydraulic levels, green means ok.
Now my next problem is figure out why one side track is slower than the other. And my hydraulic oil is milky. Is there a way to get rid of the water or do I have to replace all 55 gallons of hydraulic oil?
There are 3 solenoids where the battery is located. What are these for does anyone know? Can it be a lazy solenoid causing one drive motor to be slower?
You could try switching the lines(at the rotary manifold) to the drive motors and see if the problem follows the control swap... if not then probably an issue with the actual drive motor. Also did you pull all the oil/goop out of the base before replacing the swing motor gearbox?
I also have the same problem with a lagging final drive on one side , I agree with GregHD , I also have a 1990EX150 and according to what I have read it is a EX150-1. I also have an issue of the final drive working barely at half speed , and really sluggish I am betting my money its a leaky seal within the drive itself. I just bought this machine and looking for more info if you stumble across any. thanks Z
With the drives it all depends on what tasks is easier to perform to you, check the pressures or perform the diss assembly and do the mechanical inspection. If it was me I would check the hydraulics first. I would do a stall motor comparative pressure and case drain flow tests between two motors. Ronsii has a good idea too, about the swapping the motor hoses!
Good day We only have a dash 5 hydraulic information but if your machine is alike you can test the crawlers by bottoming out the arm while you drive the tracks - this has the effect of combining the pumps flow to the crawlers, if you still have a power loss to one side it is either the motor or central passage. If you have a hydraulic schematic we can help some more. Kind regards Uffex
Good day A contact came up with the attached hope it helps. Kind regards Uffex
Good day A couple of observations the water content in your fluid could spell damage to a lot of components including the main pump, suggest you drain & clean out as much as you can fill up with new.. Attached information that may have been overlooked can cause the pump to be noisy. Kind regards Uffex
Just my two cents reseal rotary manifold the chances of the seals being in good shape is low. Change hydraulic oil and filters .To stop ingestion of water it's probably lids on hydraulic tank or boom cylinders need resealing
Wait a minute! You have water in the oil?! In this case - check the strainer on the inlet adaptor of you pilot valve ( pedal valve for corresponding track motor in your case ) for hard black deposits!
I'm interested in what you know tva ?
I know three things about hydraulic oil: 1) quality hydraulic oil supposed to have additives in it which resiste emulsification, if your oil emulsified ( milky ) it means you have A LOT of water in it! 2) water in oil will make hard carbon deposits in small crevices ( strainers ) 3) airation of oil will create jelling.
Did you ever sort out the slow tracking issues?
No I haven’t used the machine since I changed the swing motor seal. It’s just sitting there.
Thanks for the reply, thats a pity about being parked. How did you know the seal in the swing motor was bad? Was it leaking externally and clearly visible? Thanks!
Yes it was leaking out of the bearing area and the gear oil was always low. I had to keep refilling it. My neighbor just borrowed the machine the other day, says the hydraulic oil is somehow making its way into the gear oil and is overfilling. The swing motor is whining aswell. That’s a new problem I’ll need to look into when I go up there.
Any luck on slow travel motor or is it still parked like mine?
Sold it