Hitachi ex220-3 stalling

[natetate100]

Hey guys, my Hitachi ex220-3 is stalled. It will start up amd idle but is bogged down when it revs up it will not go full throttle as it is bogging blowing black smoke everywhere. I have put on a new angle sensor and differential pressure sensor. I also switched the silonouds on the back of the pump to see if it would go out of being stuck in full stroke it did not help. Is there anything else it could be? Any help would be majorly appreciated. Is there any way to get it out of full stroke?

 

[thepumpguysc]

If u have a mechanical inj pump, it sounds like a fuel supply issue.
Check the banjo bolt below the hand primer on the supply pump bolted to the side of the main inj pump.. it should have a filter screen IN THE BOLT..
they clog all the time.!!
Good luck

 

[natetate100]

I already cleaned it as well. Its getting plenty of fuel, because if I get it to where I can have something up amd let it go down the motor revs up. Today I also cleaned and rebuilt the prv's for the boom, stick' and bucket valves. I also switched the pump solenoid and switched pugs trying to get it to go to the low side of the pump no luck.

 

[Universal Parts]

The air intake is blocked. 1. Check whether the air filter element is dusty. 2. Start the machine at full throttle to check whether the air intake pipe makes any squeaking sound or is deformed. 3. Check whether the supercharger is leaking oil.

 

[natetate100]

I took the filters out and tried it no luck. From what I can tell the pump is stuck in full vane position

 

[Universal Parts]

The filter is fine, but what about the intake pipe? Is it deformed? I think it's the lack of air intake that caused the full fuel to stall.

 

[Diesel Dave]

Did you follow the installation procedure and adjust the angle sensor to spec (4.40v)

 

[natetate100]

Yes sir, also I did the voltage for the dp sensor as well.

 

[natetate100]

Universal parts. The intake pipe looks good.

 

[Diesel Dave]

If you are questioning if the hydraulic pump is in max displacement, just check the angle sensor output voltage. Max displacement is 4.40 volts , minimum displacement is approx 2.0 volts.
With the engine running and controls in neutral the DP sensor output voltage should be 4.5 volt.

 

[natetate100]

Ok ty for the information. I'll check it out.

 

[ExcavatorPartsVincent]

I would keep the diagnosis separated from the parts decision here. If the pump is really staying at max displacement, write down the actual voltage and pressure readings before buying anything else.
Good notes to collect:
- angle sensor voltage at idle, neutral, and loaded condition
- DP sensor voltage with engine running in neutral
- whether the pump control pressure changes when a function is commanded
- pilot pressure and pump delivery pressure on both pumps
- what happens to engine rpm and black smoke when the load is released
- whether the pump solenoid plugs and wiring have correct supply/ground, not just swapped plugs
If it later turns into a parts order, do not buy by "EX220-3 pump parts" alone. Send the pump tag, regulator/control block photos, solenoid photos, shaft/flange/port photos and the test readings with the quote request. For Hitachi pumps the wrong regulator, angle sensor setup, connector or port layout can make a replacement look correct but still leave the machine in the same full-stroke/bogging condition.