• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

Hitachi Ex120 Problem

Joined
Feb 17, 2012
Messages
9
Location
England
OK thanks very much for your help.
Can I replace the sensor without removing the main pump from the machine?
If so, will i be able to line it up properly in situ?
Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!
do you think its significant that the DP sensor has been disconnected before I bought the machine?

Richard
 

rgl726

Well-Known Member
Joined
Sep 11, 2010
Messages
175
Location
cebu city, philippines
OK thanks very much for your help.
Can I replace the sensor without removing the main pump from the machine?
If so, will i be able to line it up properly in situ?
Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!
do you think its significant that the DP sensor has been disconnected before I bought the machine?

Richard

my technique is removing both wires of the 2 pump soleniods. just make the pilot commands easy(push very little on the controls) because the pump will be at full swash. this way you can load it to a selfloader.

disconnecting the DP sensor is not a good idea.:)

its ok to use non genuine as long as you can hit the right one.:D

sooner or later you'll get use to the prices of this parts.;)
 
Last edited:

-3Doc

Well-Known Member
Joined
Jul 29, 2009
Messages
119
Location
British Columbia
Occupation
Ticketed HD Mechanic
OK thanks very much for your help.
Can I replace the sensor without removing the main pump from the machine?
If so, will i be able to line it up properly in situ?
Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!
do you think its significant that the DP sensor has been disconnected before I bought the machine?

Richard
You need the manual to replace the sensor and set the voltage properly. You can put the machine into a limp mode in order to get it home. If you look on the bottom of bothe pumps there is a four bolt cap plate over the end of the swash cylinder pistons. If you remove that plate you will see that it has a peg sticking up from the underside of the plate, if you turn the plate 90 degrees and replace it back in the hole then the pin will put the pumps into about halve swash and they will stay there the you can get the machine home if you feather the controls. As for your problem it sounds to me like the pump displacement solenoids, they tend to work fine when cold but as the machine heats up the coils break down and they quit working then the machine goes to full swash and stalls. Good luck.
 
Joined
Feb 17, 2012
Messages
9
Location
England
Hi again
I do have all the workshop,tech and parts manuals for this digger, but I am hoping the guy I purchased if from will be in charge of repairs, when he returns from holiday.
Is there any thing else on the EX100-2 machines that i should be wary of? I had heard that the ex100-3 were a bit unreliable, and I couldnt afford a ex100-5
She has done 7000 hrs, there is no rock in slew ring at all, tracks are ok. A little slop in the main pins, but not much.
Is the slew dampering valve on the bottom of the main boom supposed to click?
Will she be ok without a DP sensor/or Should I get it re-wired back in? its probably bust in the first place, which is why its been removed!!!
many thanks again

Richard
 
Joined
Feb 17, 2012
Messages
9
Location
England
Hi Again

I looked at the plate under the pump that you said to rotate by 90 degrees to move the swash plate to half, the plate is oblong, so I cant turn it through 90 degrees, 180degrees yes, 90 no!!!
Any more ideas??

Richard
 

spitzair

Senior Member
Joined
May 4, 2007
Messages
1,010
Location
Squamish BC (Home), Slave Lake, AB (Work)
You need to pull this plate straight down, it has a long finger on top of it. Once you have it pulled all the way out turn it 180 degrees then shove it back in. This will push the swashplate piston up and destroke your pumps to limp mode. You may need to undo the small hydraulic line on the top of the pump to relieve the pressure in there to be able to push the piston up. At least that's how it works on my 200-2, I imagine yours would be similar or the same...
 

seadara

Member
Joined
Jan 28, 2012
Messages
7
Location
INDIA
HITACHI EX120-3 Angle Sensor setup

Hello -3DOC, Could you please help me in setting Angle Sensor ? I need manual and voltage setup procedure. Please.
 

000496519

New Member
Joined
Sep 23, 2011
Messages
4
Location
Grande Prairie AB
I have read all of the threads that have anything to do with the HITACHI 200LC. I have checked fuses, computer is operating normally

Out of the 4 sensors they all tested fine. ALTHOUGH the angle sensor was a little suspect.

STEP 1: I removed the sensor and checked with a small screwdriver to see if the fork on the swash plate was intact. I could rotate the fork freely which indicates that one of the arms must be broken.

STEP 2: I put my multimeter in parallel on the ground and sensor return wires and adjusted angle sensor to roughly 1.45 or 1.54 Volts which is where it should sit in normal operation ** (I may not be accurate with the set voltage values because it has been several months since doing this but a guy with lots of experience had told me to set it to this so I am not making this number up) ** I then reinstalled the angle sensor.

STEP 3: I got a friend to start the machine and operate it while I monitored the voltage..... :eek: WHAMMO the machine ran awesome no stalling or slow operation. :confused: THEN.. the voltage changed and the machine acted up again. **( I cant remember which did what but from what I gathered after a few tests. Either when the voltage goes above or below the value that I had originally set it causes one of these two things.

ISSUE 1: the machine goes into a limp mode where the engine is at high rpm but all the hydraulic functions are slower than molasses.

OR

ISSUE 2: the machine runs fairly normal except it will stall out when you run the hydraulics full out (two functions at the same time or fully extended or retracted)

My question to anybody is. Has anybody had this problem before? What have they done to fix it? Is it possible to tear down the pump and replace the fork? Does anybody have a rebuilt pump? Is there a manual that shows step by step instructions for tearing down the pump?

Or is my troubleshooting completely effed :eek: and I am so far out I should get my head checked? ;)
 

-3Doc

Well-Known Member
Joined
Jul 29, 2009
Messages
119
Location
British Columbia
Occupation
Ticketed HD Mechanic
I have read all of the threads that have anything to do with the HITACHI 200LC. I have checked fuses, computer is operating normally

Out of the 4 sensors they all tested fine. ALTHOUGH the angle sensor was a little suspect.

STEP 1: I removed the sensor and checked with a small screwdriver to see if the fork on the swash plate was intact. I could rotate the fork freely which indicates that one of the arms must be broken.

STEP 2: I put my multimeter in parallel on the ground and sensor return wires and adjusted angle sensor to roughly 1.45 or 1.54 Volts which is where it should sit in normal operation ** (I may not be accurate with the set voltage values because it has been several months since doing this but a guy with lots of experience had told me to set it to this so I am not making this number up) ** I then reinstalled the angle sensor.

STEP 3: I got a friend to start the machine and operate it while I monitored the voltage..... :eek: WHAMMO the machine ran awesome no stalling or slow operation. :confused: THEN.. the voltage changed and the machine acted up again. **( I cant remember which did what but from what I gathered after a few tests. Either when the voltage goes above or below the value that I had originally set it causes one of these two things.

ISSUE 1: the machine goes into a limp mode where the engine is at high rpm but all the hydraulic functions are slower than molasses.

OR

ISSUE 2: the machine runs fairly normal except it will stall out when you run the hydraulics full out (two functions at the same time or fully extended or retracted)

My question to anybody is. Has anybody had this problem before? What have they done to fix it? Is it possible to tear down the pump and replace the fork? Does anybody have a rebuilt pump? Is there a manual that shows step by step instructions for tearing down the pump?

Or is my troubleshooting completely effed :eek: and I am so far out I should get my head checked? ;)

If you can turn the shaft in the pump easily were the angle sensor goes in, then that is your problem!! That shaft is hooked to the swash plates on the pump and should only move when they move. There is a small pin that holds the fork to the swash plate and that falls out causing your problem. If you are comfortable you can buy the gaskets and remove the pump heads and repair the problem, but you shoul have instructions or a manual. you must drain the hyd oil. PM me if you need manuals.
Thanks -3doc.
 

000496519

New Member
Joined
Sep 23, 2011
Messages
4
Location
Grande Prairie AB
If you can turn the shaft in the pump easily were the angle sensor goes in, then that is your problem!! That shaft is hooked to the swash plates on the pump and should only move when they move. There is a small pin that holds the fork to the swash plate and that falls out causing your problem. If you are comfortable you can buy the gaskets and remove the pump heads and repair the problem, but you shoul have instructions or a manual. you must drain the hyd oil. PM me if you need manuals.
Thanks -3doc.

I have the service manual and parts manual but it is a hard to follow manual. Is there another manual that breaks it down into steps with torque specs out there that you know of. If so I'll take one of those for sure.
 

TraxterMaster

Member
Joined
Mar 10, 2010
Messages
13
Location
Ottawa, Canada
Occupation
Farmer
Anyone know a good place to get a replacement wiring harness for a EX100-2. mine is all cracked and the machine keeps having intermittent issues and blows fuses. I already changed the EPC and not looking to change an other one that soon.
 

spitzair

Senior Member
Joined
May 4, 2007
Messages
1,010
Location
Squamish BC (Home), Slave Lake, AB (Work)
Anyone know a good place to get a replacement wiring harness for a EX100-2. mine is all cracked and the machine keeps having intermittent issues and blows fuses. I already changed the EPC and not looking to change an other one that soon.

I bought mine for my EX200-2 at Wajax. Cost a few bucks but well worth it, no more issues now, machine runs like new!
 

pemolitor

Active Member
Joined
Feb 27, 2008
Messages
29
Location
Iowa
I am finally getting back to figuring out my machine. found 4 connectors off of the pilot silinoids not connected. need to find the wiring harness to hook them back up. tried the schematic from page 12 or 13 of this thread.... but i can't blow it uo enough to see.
 

chuck42

New Member
Joined
Jul 18, 2012
Messages
2
Location
canada
Hello everyone, i have a Hitachi EX200LC that is having the a problem of one track being slower than the other> for about 1 hour the machine works fantastic however when she is running at temp is when it will start to get really bad, by the end of the day it will almost not move, all i have done so far was inspect fluid levels and for visual leaks... not sure if this matters at all but when i pulled the plugs to check the fluid level i noticed the slow side had a considerable amount of pressure build up compared to the other, not sure if that matters!!
 

santikko

Well-Known Member
Joined
Aug 26, 2012
Messages
57
Location
finland (bad english)
hello. i`m having too some issues with ex100-2. toasted pvc, and a lot of black smoke out of motor when try some functions. i think my problem is in the angle sensor, or the rpm sensor when i read this topic. it has burned some fuses too, including pvc fuse. cant go near the machine for over a week because of my work. could someone very kind person email me the instructions to idle the angle sensor? and maybe how to test it if its okay. my emal is santikko(at)offipalsta.com. any mechanic data and manuals around this issue is welcome. this topic is great! :)
 
Top