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I have an Ex120-3 I’m experiencing the engine being

Customer Question
I have an Ex120-3...

I have an Ex120-3 I’m experiencing the engine being overwhelmed when I am operating 2 or more controls or when I am pulling the dipper arm in mid stroke

Mechanic's Assistant: What is the complete model and serial number of your machine?

Hitachi ex120-3 mfg number is ***** - 42443

Mechanic's Assistant: Is there anything else the Construction Mechanic should know before I connect you? Rest assured that they'll be able to help you.

Yes the machine was recently fitted with a sinocomp hydraulic conversion kit

Submitted: 10 months ago.Category: Construction and Road Equipment
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Customer reply replied 10 months ago
It feels like the hydraulic pump is at full swash when the machine is mid way through an operation like the dipper arm swing or slewing etc.
I checked banjo bolt fitting and fuel filter and line to engine and all are clean
Answered in 19 hours by:
10/7/2021
Mechanic: Dan, Technician replied 10 months ago
Dan
Dan, Technician
Category: Construction and Road Equipment
Satisfied Customers: 14,654
Experience: 17+ yrs. shop and field experience with all major brands of heavy equipment and trucks - 1995 WyoTech graduate.
Verified

Hi, My name is***** will be glad to try to help. We can follow up as needed on here. Professionals are not employees of the site but users of the site and help on here as time allows depending on their daily schedule.Sorry to hear you're having these troubles with this machine. Check for any fuel leaks or restrictions between the fuel tank and fuel pump as well as for contamination of fuel after replacing your fuel filters. Check for any air intake leaks or restrictions as well to be sure that the engine is running at its peak performance. Change your hydraulic filter and inspect the existing filter internally for what looks like fine metal or glitter indicating a pump or component failure existing on this machine. If all this is clean, you'll want to have your pump pressures and flows tested to confirm whether or not they are within the factory specifications of your model and serial number machines service book.Check your control valve spools and the relief valve cartridges for any trash or debris as well as any other damage that would cause them to stick or malfunction. I hope you find this information helpful. Reply back with the results of these checks if any further help is needed. It's a pleasure to help anyway I can.

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Dan
Dan
Dan, Technician
Category: Construction and Road Equipment
Satisfied Customers: 14,654
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Experience: 17+ yrs. shop and field experience with all major brands of heavy equipment and trucks - 1995 WyoTech graduate.

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