Proportional solenoid valve

[Mikeyp756]

Hey guys, on my hitachi ex120-2 still has slow/weak hydraulics. Got a new solenoid valve but might have ordered the wrong one because the new one doesn’t have the adjusting bolt. And it requires a smaller pin (which didn’t come with it) and the hole is much smaller. Question can I use this valve if I make a pin?Does anyone know what size the pin is?

 

[mg2361]

Which solenoid valve? Are you talking about the solenoids on top of the pumps? Post a picture of the old solenoid and new solenoid. If you are talking about the DP sensor, then the new one's are not adjustable.

 

[Mikeyp756]

Which solenoid valve? Are you talking about the solenoids on top of the pumps? Post a picture of the old solenoid and new solenoid. If you are talking about the DP sensor, then the new one's are not adjustable.

The proportional solenoid valve. Just wondering if I can use the new one. If I can, what do I do about the pin. The old pin is too big.

 

[mg2361]

I don't have an answer for you. I have always replaced the solenoid coil on top of the pumps with the cast valve it is attached to as an assembly (first picture). If it is from the solenoid valve block like the second picture then again I don't have an answer. LAUCHAU would be the guy to contact for that answer.

 

[Mikeyp756]

I don't have an answer for you. I have always replaced the solenoid coil on top of the pumps with the cast valve it is attached to as an assembly (first picture). If it is from the solenoid valve block like the second picture then again I don't have an answer. LAUCHAU would be the guy to contact for that answer.

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Thanks mg2361, it the 2nd picture. How do I find this Lauchau ?

 

[mg2361]

Top left of the forum page is a drop down titled members. Go in there and search LAUCHAU and when his username comes up click on it. Then you can see there will be a link to start a conversation. Start the conversation and ask him your question.

 

[Mikeyp756]

Top left of the forum page is a drop down titled members. Go in there and search LAUCHAU and when his username comes up click on it. Then you can see there will be a link to start a conversation. Start the conversation and ask him your question.

tried that he’s not listed.

 

[mg2361]

He comes up when I search, interesting.

Try this thread and click on his name.

https://www.heavyequipmentforums.com/threads/komatsu-pc88mr-8-hydraulic-trouble.80295/#post-851543

When you click on his name you will get this

 

[Mikeyp756]

Got it thanks. Spelt it wrong the first time

 

[LACHAU]

Thanks for your believe.
They are different then they can not be interchangeable!! One is solenoid valve (don't have adjusting bolt) and the other is Proportional solenoid valve.

 

[LACHAU]

and they are also different the some parts!!

 

[excavator]

I don't believe they will interchange. Different setup.

 

[Mikeyp756]

and they are also different the some parts!!


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Ok thank you

 

[mg2361]

my hitachi ex120-2 still has slow/weak hydraulics.

You mentioned slow/weak hydraulics. All functions or one function? Did you try swapping the two solenoid valve assemblies on top of your hydraulic pump to see if your condition changes? Also make sure your fuses are good, especially the controller 1 A fuse.

 

[Mikeyp756]

the 1 controller fuse was blowing so I replaced both valves on top of pump. Fuse no longer blows but no change. Don’t think all functions are slow/weak but travel and swing are real bad.

 

[natemarine]

I am trying to get to the bottom of similar issues, new to this forum, has anyone actually solved this? It seems like the conversion kit isn't the right answer and I haven't seen a solution in all my reading yet.... I bought my 120-3 a few years ago and it ran perfect for a while but all the same hydraulic problems as everyone else.... Weak hydraulic functions, a load on the hydraulics when I start it , excess vibration, dead heading (stalling) been dumping money in this problem for too long now I'd love to get to the bottom of it..... thanks nate

 

[mg2361]

I am trying to get to the bottom of similar issues

Hi Nate. This post only started on Saturday so just follow along to see if it lands on a resolution. I know you have a post started so we'll try to keep going on your thread to keep the two machines separate.

 

[mg2361]

the 1 controller fuse was blowing so I replaced both valves on top of pump. Fuse no longer blows but no change. Don’t think all functions are slow/weak but travel and swing are real bad.

Has pilot pressure been checked to eliminate that as a cause for slow hydraulics?

Do you have a service manual? Did you check the adjustment for the DP sensor and the pump angle sensor?

Did you try and get the blink codes from the controller?

 

[Mikeyp756]

Has pilot pressure been checked to eliminate that as a cause for slow hydraulics?

Do you have a service manual? Did you check the adjustment for the DP sensor and the pump angle sensor?

Did you try and get the blink codes from the controller?

. Don’t know how to check pilot pressure but main pump pressure has been checked. DP sensor has been checked and angle sensor has been changed replaced. Someone told me little Dot on angle sensor is supposed to point away from the label on the sensor. Manual says opposite.

 

[mg2361]

But there is still a voltage adjustment that has to be made to the angle sensor to insure the information getting back to the controller is accurate.