Hitachi EX60 Help

[Bakernator]

So I have an issue with my 1995 EX60 where it started to start hard now it won’t start without the throttle stepper motor bypassed. Right now I have the throttle unhooked from the stepper and the HYD pump solenoid unplugged. I can get the machine to start and run with the throttle manually manipulated but it will start to bog down after about 30min of running, even with the HYD solenoid unplugged and stepper motor unhooked. Could it still be the pump swash solenoid even if it’s unhooked? What else am I missing?

 

[mg2361]

I am not sure but I believe having the solenoid unplugged puts the pump to maximum displacement. The solenoid should be energized to put it in the "destroked" position. Maybe Lachau can answer this question.

 

[LACHAU]

So I have an issue with my 1995 EX60 where it started to start hard now it won’t start without the throttle stepper motor bypassed. Right now I have the throttle unhooked from the stepper and the HYD pump solenoid unplugged. I can get the machine to start and run with the throttle manually manipulated but it will start to bog down after about 30min of running, even with the HYD solenoid unplugged and stepper motor unhooked. Could it still be the pump swash solenoid even if it’s unhooked? What else am I missing?

I am not sure but I believe having the solenoid unplugged puts the pump to maximum displacement. The solenoid should be energized to put it in the "destroked" position. Maybe Lachau can answer this question.

"the solenoid unplugged puts the pump to maximum displacement. The solenoid should be energized to put it in the "destroked" position"...Yes, This is correct.
But the main pump has the other way to control. It's been controlled by pump delivery pressure also.
So that, if the regulator of pump is working well ==> the engine would not over-load.

 

[Bakernator]

Do you think I am on the right path with the Solenoid valve? Or would it be the regulator on the pump? I am doing a lot of traveling on the machine and going over the service manual it looks like travel motors use a lot of flow. I dont get why it would work ok for XX amount of time and then just start acting up.

 

[Bakernator]

I finally had some time to work on the hoe. I checked out the solenoid and everything looks to be working correctly. I ended up changing out the EC Motor, position sensor, and throttle cable. I’m able to start the machine now, but it looks like i need to do a relearn on everything. How is that done? The bad news is it still starts acting up after about 20/30 minutes. I’m thinking it might be fuel related, but not sure how to check or why it would take so long to act up. I did notice this metal piece hanging around the injection pump. Anyone know what that is?

 

[mg2361]

Looks like it might be the anti-tampering seal. Is it lead with a wire squeezed in it? If it is that it was attached to the pump to prevent adjustments. Hopefully Lachau will get you the relearn procedure.