Hi, my father had bought a Hitachi EX200-2 excavator and from the very start we have had problems with it. The machine has a Manual regulator installed so it’s a manual machine now and all the electrical wires that were present before has been removed before we bought it. The problem with the machine is that at start it operates well but after nearly 10 minutes all the hydraulic operations become slow and powerless. We have installed a brand new main pump(new valve plate, pistons, cylinder blocks and head block), took the control block out and changed all seals and O-rings (over roll), installed a brand new aluminium hydraulic oil cooler, changed the centre joint seal, installed a new charge pump. We have done all this as one by one each mechanic asked so basically the hydraulic system has been made new but the problem still remains and money has just been spent. I’m just tired of this machine and am asking if anyone out there can help me please. All the hydraulic operation becomes slow and powerless after a while and the engine gives off too much smoke. Please help!!!!........
Just a shot in the dark, but injector/ injection pump problems?
So do you think there is a problem with the injectors??....
The machines hydraulic system at the start is fine , a bit of power but later all actions become slow and power-less but the engine loads from the start...gives of smoke
I dont know much about hydraulics, but even though it has been converted from electrical to hydraulic control, there must be some type of adjustments on the hydraulic control. Pump angle may not be responding to demand properly. Just my thoughts.
Do you know how to adjust or where to adjust??....pressure settings??...
I dont know what has been changed to make it non electrical but you need to find out if it is the engine choking or the pump pulling it down,i am confused because pump overstroke will load the engine and cause black smoke from start but the hydraulics will be fast as pump understroke will make the hyds.slow but the engine will run free . Does it do this at the same time or are you having different problems at different times ? There is a member here I think itis sk120 that keeps talking about some manual kit .that may be what you have i would pm him,that is the only time i have ever heared of such a thing till now.I f it was still factory electrical i could be more help.Hope This helps A bit anyway
Yes, It has a manual kit installed on the top of the pump…some people call it the “manual regulator” or the “manual kit” which changes the machine from an electronic to manual. At the start the hydraulics are good but not too power- full(A little bit fast) but after nearly 10 to 30 minutes of operation the hydraulics slows down and engines makes a sound like it’s giving up and gives black smoke. Thanks for your help….really appreciate your comments….
Does the engine still smoke and pull down with all levers hands off ? like i said we have got to tell if it is pump load or engine for sure/ Does the pump still have the little 4 bolt plates on top and bottom of the stroke piston housing?
It smokes and pulls down when the levers are applied...as soon as levers are let gone the machines gives smoke but very very lillte....i think the pump is loading the engine...yes i have the four bolt plate on the pump but only at the bottom of the pump...on the top there is a "Manual kit" installed....the four bolted plate at the bottom has a long bolt in the centre of the plate...which can be adjusted.....please what do you think is the problem???..............
Can that bolt be adjusted with the plate installed ?
yes it can....with a 5/8 spanner to unlock the lock nut and a shifter to adjust the bolt....but i dont know the proper adjustment...should the bolt be adjust by pressure setting...if so how and where should the pressure be tested??....to adjust the bolt??....
That bolt is part of the kit which i know nothing about but I think your trouble is pump control I guess if there is no way to get help from the kit maker I would take it apart and try to see what does what. The stroke piston moves down to stroke & up to destroke I am just guessing but that bolt is a stop or has a spring inside to destroke the pump you can remove the plate and push the piston all way up and lock it there with the bolt,shims or whatever and run it at mim. stroke just to test, it will be very slow but it will dig and this will at the least narrow down the problem.
Ok thanks for replying. I'd just like to ask about the stroke piston which is called the servo piston, that piston has a ring. Do you think the problem could be the ring??....because i've put on the new pump but haven't changed the servo piston and it's ring
someone told me that there is a bypass on my pump but my pump is new...i installed a new pump last year....just not the servo piston and the ring....
I'm not sure how the new pump wouldn't come with the servo piston and ring - those parts are right inside the head of the pump. Did a new pilot pump come on the new pump? Sounds like you need a guy out there who knows mobile hydraulics. Has anyone looked in the DP system - the relief valves, pilot pressure? Need to diagnose before throwing any more parts at it. The pilot system is definitely something that can affect the whole machine. What is pilot pressure when the machine is warmed up? It's going to be tough to try to diagnose this non-stock control system without literature. I have never heard of that before. Is there anything about it on line or is it something some guy fabricated?
? nothing I can think of on that pump that would be described with "bypass" there's a plate on the bottom of the servo you can rotate 180 deg and push the servo to the 70% (I think) displacement position
I agree that the pump regulater needs attention but check the turbo for tring to lock up after runnning that 10 minutes......... seen it happen before.. power goes away and engine smokes like a freight train
Well we just ordered only the 14 pistons, 2 Cylinder heads, 1 valve plate and the Head block. I didn’t realise that I need to change the servo piston and ring also because I didn’t know its function. Yeah I’ve near replace all of the hydraulic system…we ordered the pilot pump separately….just haven’t changed the Manual kit and the servo piston and rings…nah!!...no has looked at the DP system….I’ll have to check the pressure….I’ll let you know soon….thanks for assisting and pitching in though ….I really need help with this machine…it’s just given me headaches!!!....
oh yes!!....i forgot to mention!!....we placed a new turbo also....my dad thought that the source of too much smoke was the turbo....so we installed a new one....still no change....
you want to check several pressures. Pump discharge obviously, but also LS pressure as the DP system opens based on pressure differential. Need a service manual to follow that through. And definitely watch pilot pressure as the oil warms up. If you aren't getting full pilot to the cab, DCV spools won't be fully shifting when you use the controls.
Thanks…well I don’t have a service manual with me….do you have one??....can you send me a scanned copy if possible on areas to test the pressure…seems like you know more about hydraulics than I ever will….
Hello my ex200-2 is in the same condition as your and i finally given up with the manual regular so i am trying to go as original as possible but i need some help in finding out the length of that octagon shape bolt on the plate below the pump the one on my machine have been cut so could anyone tell me that measurement please and thanks in advance
Hi Aaron. Sounds like you have what Hitachi call a pump mecha-regulator. I have fitted a few of these in Australia over the years and from memory the regulator that sits on top of the pump head has shims on the internal spool. you add to increase absorption torque and in your case you remove them. Some where I have some info one it however I am unable to access at the moment. Pull the block off the pump head and remove a couple of these shims and see what happens. I see you are in Fiji Did you buy the machine there or did you import it? Regards Mike
Thanks for your reply, I imported the machine, I recently replaced the cylinders and valve plate in the pump it really needed to be look at. That stopper I asked about at the bottom of hydraulic pump it was made shorter and i need to put it right but I NEED THE CORRECT LENGTH could you please help me with that. Man I never got any good response from that regulator I installed, I try everything I read up on and ideas that was given to me so as I made the repairs on the pump I was hoping to go back as original as possible. i attached a picture of what i am specking about I hope it went OK.
The pin you are talking about should not come into the equation, It is there to allow you to move the excavator in case of a total electrical failure. You probably know that it fits into a hole in the servo piston and if you remove the cover and turn it it will interfere with the piston and stop the pump from going to full stroke and stalling the engine.I don't know what the original length should be. Do you have information on the mechanical regulator?? Are you sure that it is installed correctly ?? I have the Hitachi service bullion and it is pretty vague. Is the mechanical regulator from Hitachi or from elsewhere Did you install the mechanical reg?? If not someone has had a pretty good reason to do so. As mentioned before these machines are a electronic nightmare when they get old so I would be very hesitant in trying to get it back to electronic control. Regards Mike.
Hello Pfpm, I will upfront with you I am an architect with no previous knowledge of any mechanical or electrical work so i am being educated by this trouble ex200-2 machine so i am very thankful for all your help. Now base on what you have mention about the pump I will nor border about it. 1. The regular is from Hitachi 2. I am the one who install the regulator when I purchased the machine the stopper at the bottom of the pump was rotated 180 degrees and it was working but the movement was slow and the pump was making noise but i was able to do two jobs with it then about a year later it got really really slow so base on the information I gathered I was told to install a regulator which I did but it didn't help, I don't know if its because the pump was bad or the installation was bad. 3. If you have any information on the installation of that regular please share it with me I will be very grateful Regards Jimmy
Hell Mike here is my email address so you can send that information to me [email protected] Jimmy
Pfpm do you know the part number for this mecha-regulator? I've only ever seen the Chinese kits. Are there instructions for plumbing and adjustments? Experiencing pump control issues with a 120-2.
Hello McLean, it is stated on the installation manual as the KIT NO. for the 100/120-2,3 which is 9227242 and that is from Hitachi. I bought my own from the Chinese which comprised of both the 100/120-2,3 and 200/220-2,3 and its on my EX200-2 presently but I am in the process of putting it back original so I have purchased the EC computer which was burnt, the N, A, P and DP sensors if these parts mention doesn't make it work then i know i will have to change the harness base on its condition but i have done some repairs on it, so let see what will turn out. Hey let me inform you that the mecha-regulator is to bypass the electrical system connected to the pump so if your pump is giving trouble it will not work properly.
Recently,I bought a manual regulator and installed it on my ex200-2 main pump in case of electric failure. There are two stoppers in the kit and i put one in the manual regulator. but i have no idea where to install the rest one. i can't find the servo piston adjust bolt which is a part of the manual kit, as you people discussed. Please advise me that in the attached photos where those are to be replaced or assembled. Thank you all for kindness.
Hello only one that is needed. Do you have the installation manual for the regulator. Here is my email [email protected] email me i will send you the information so you can get it done.
Hello just came across this thread and we have a customer with the same problem. We ordered the Manuel kit and it came with no instructions and the suppler is no help. Is there anyway someone on here that has the instructions could email them to me it would be greatly appreciated. Email [email protected]
Welcome to HEF Charles ! You should really have started a new Thread with your question with the specific machine model and serial number. You will want to add what is specifically wrong with the machine as well. Maybe the solution is simple (I know, wishful thinking). Hope you find your answer .