Hitachi EX200-1? Tobis TBP112DT Pump Loaded

[Balistic]

Put a replacement engine in my Hitachi ex200, believe it is a -1. When trying to start the engine it appears that the swash plates on both pumps are at full angle and loading up the hydraulic's. Does anyone have any experience with these pumps or ex200-1. We can take a hydraulic line off and start the engine fine. Just can't find out how to unload it/ relieve the pressure. There's no computer or electronics. Cheers any help much appreciated.

 

[garyw]

Put a replacement engine in my Hitachi ex200, believe it is a -1. When trying to start the engine it appears that the swash plates on both pumps are at full angle and loading up the hydraulic's. Does anyone have any experience with these pumps or ex200-1. We can take a hydraulic line off and start the engine fine. Just can't find out how to unload it/ relieve the pressure. There's no computer or electronics. Cheers any help much appreciated.

Does any of the actuators try and move when your cranking the engine? The control valve is an open centre valve so all pump flow, irrespective of whether the pumps at minimum or maximum stroke, will return though the centre passage of the control valve and straight back to tank. Have you had pressure gauges on either pump when cranking to verify there's pressure in the pump?

 

[lantraxco]

Does that have the small diameter mechanical control rods, one for each pump that work off the control lever linkage? Wild guess from thirty years ago working on Hitachis.

 

[Balistic]

Control valve.

Does any of the actuators try and move when your cranking the engine? The control valve is an open centre valve so all pump flow, irrespective of whether the pumps at minimum or maximum stroke, will return though the centre passage of the control valve and straight back to tank. Have you had pressure gauges on either pump when cranking to verify there's pressure in the pump?

Hi Gary, what actuators are you referring to, there are no visible actuators that we know of. We don't have a gauge on hand to measure any pressures. Do you have any drawings or manuals, for the control valve.

 

[bwmwaima]

Was this happening before engine change. Which hose are you taking off to make starting easier.

 

[Balistic]

Still no luck yet

Was this happening before engine change. Which hose are you taking off to make starting easier.

This wasnt happening with the previous engine. I'll try and post some pictures of the control bank and pump. I have circled the house that was removed in red.
Thanks for everyones help so far.

 

[bwmwaima]

That line you marked where does it go to. When engine was removed did you leave pump in there or drain and disconnect hoses and take pump out with engine,
just trying to retrace steps taken, as hydraulics were working fine before engine removal.

 

[lantraxco]

That's a copy of the Kawasaki K3V pumps, and it looks like you've got wires hanging loose? Might be part or all of the problem....

 

[garyw]

What year is the machine? Are you sure it's a EX200-1? I'm looking at a EX200-1 service manual and the hydraulic pumps look totally different to what's in the picture. The actuators i'm referring to are just the arm/ boom, bucket cylinders as well as the travel and swing motors. The control valve also looks very different. Maybe i'm getting mixed up with the machine model. The EX200-1 has an open centre control valve. Basically any oil flow should flow through the control valve and back to tank with very little restriction. This should never load up the engine unless a spool is stuck and one of the actuators are trying to move( a cylinder or a motor) Some models of hitachi had a closed centre control valve. So basically when the oil hit the control valve, an unloader valve had to open at a set pressure and dump everything back to tank. If this unloader valve isn't working correctly it may load the engine up too much.

 

[Balistic]

bwmwaima - pump was removed with engine, hydraulics have been drained and refilled.
lantraxco - correct it does look like a Kawasaki K3V Pump - All wires were previously disconnected before the engine replacement.
garyw- unsure on year or model of excavator on further googling the Main Control Valve bank in the previous photos look like a Hyundai Robex 200W-2 Main control valve

https://www.google.co.nz/imgres?img...hVB_GMKHTkmB8k49AMQMwhlKGMwYw&iact=mrc&uact=8

Definately a Hitachi Excavator, but unable to locate any plates with the model number or serial number.
Was imported from China, was fitted with a mitsubishi 6d14-3.

 

[yeahyo]

I have a grey market 200-1. '92 I believe and looks nothing like that. Has two pumps. Pilot controlled swash plate thru a solenoid control valve. Isuzu engine

 

[bwmwaima]

bwmwaima - pump was removed with engine, hydraulics have been drained and refilled.
lantraxco - correct it does look like a Kawasaki K3V Pump - All wires were previously disconnected before the engine replacement.
garyw- unsure on year or model of excavator on further googling the Main Control Valve bank in the previous photos look like a Hyundai Robex 200W-2 Main control valve

https://www.google.co.nz/imgres?img...hVB_GMKHTkmB8k49AMQMwhlKGMwYw&iact=mrc&uact=8

Definately a Hitachi Excavator, but unable to locate any plates with the model number or serial number.
Was imported from China, was fitted with a mitsubishi 6d14-3.

Looking at valve block and plumbing , not Hitachi, looks more like Hyundai, not that it matters.

When hoses were disconnected were they left open or capped/ plugged, nothing left in them on reassembly.?

On refilling with oil were both case drain plugs in pumps removed to bleed air out ?

No electrics for pump control there for pilot controlled from valve block, should be two pilot hoses from valve block to pumps, one from left valve bank to one pump regulator, the other from right valve bank to other pump regulator.

 

[lantraxco]

Oh good God, it's a Frankenvator......