marshy
Well-Known Member
hello i have a komatsu pc220-5 and its bogging down with every movement of the bucket, could it be a solenoid any one please help 
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Excavator bogging down
- Thread starter marshy
- Start date
Per Eriksson
Senior Member
Does the engine smoke when it bogs down?
marshy
Well-Known Member
no the motor has just been rebuilt it was bogging down before the rebuild aswell but when we rebuilt it it was ok then it has gone back to bogging down again ??
marshy
Well-Known Member
the engine has about 10 hours use since rebuild
the engine free revs good we have checked fuel system and replaced fuel filter ect
the engine free revs good we have checked fuel system and replaced fuel filter ect
Sounds like fuel starvation to me. Did you check the pickup in the tank for blockage when you checked the fuel system? Try blowing the line back with compressed air and see if that fixes your problem. If that fixes your problem it will only be a temporary fix until the pickup plugs up again. If that's the case you will need to remove the tank and try and clean out the rust and crude.
Your machine might also have screens in the banjo fittings that could be plugged. Maybe someone more familiar with Komatsu can verify if your machine has them or not.
Hose collapse? Weak transfer pump?
You could try teeing a gauge in the line after the transfer pump and see if you are loosing fuel pressure.
Your machine might also have screens in the banjo fittings that could be plugged. Maybe someone more familiar with Komatsu can verify if your machine has them or not.
Hose collapse? Weak transfer pump?
You could try teeing a gauge in the line after the transfer pump and see if you are loosing fuel pressure.
marshy
Well-Known Member
we put a external tank and electric pump onto the excavator and its still doing the same thing
Haddy
Well-Known Member
Might be the hydraulic's . When it is bogging down , without operating any controls and if you run it at full throttle , does it build up pressure into any lines it shouldn't ? :my2c Haddy
Last edited:
JDFG1974
Active Member
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- Jan 16, 2013
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- Southeast / Georgia
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- Owner/Operator CLEARING GRADING COMPANY
Sounds like bad fuel or filters or collapsed fuel line . GOOD LUCK
VENT MOBILE
Member
Is this electronic flow control for the regulators on the pump because it could be a an issue with a proportional valve or in the regulator itself or inputs for the computer like rpm sensor let me know
joeblow
Well-Known Member
Sounds like a fuel supply problem but it could be the hydraulic pump stuck in full swash.How many hours on the machine?
joeblow
Well-Known Member
Could be the swash /valve plate sticking from contamination or a stuck load piston.If it is not fuel than it is probably that.I am not a komatsu guy but if the machine has a lot of hours on it and the Hyd oil is old then. I would look there.pull the Hyd filter and cut it open.
marshy
Well-Known Member
Hello thank you guys for replying,the hydraulic oil is not very old, seems to be nice and clean,can u please explain were the valve is and how to check it.there is a electronic solenoid on top of the main pump which is bolted to the engine, not sure if the wires have been disconnected or not, could that be the solenoid you are talking about.
whfh99
Member
Did you ever figure out what this was? Working on a friends PC220LC-3 exhibiting similar problems. Been sitting for a few months, got it started then it died. I think it ran out of fuel so put more fuel in, bled the injectors and it's running and sounding normal. But the moment I hit any controls, it will practically kill the engine. I mean just trying to lift the boom almost stalls the engine from mid throttle. It seems more like a hydraulic problem to me than fuel as the engine sounds fine when no load is on it.
joeblow
Well-Known Member
If you ran it out of fuel and then bled it to get it started,it sounds like you sucked all the water and crap off the bottom of the fuel tank.Before you can diagnose the power problem you should change the fuel filter.It is your cheapest option.Are the pumps controlled by a solenoid?If so then check the wiring to them and the pump angle sensor.Check the fuses as well.If that is ok then it sounds like a stuck swash plate in the hydraulic pump.If the oil is old and it has sat for a while then the water and acidic crap has ruined the hydrodynamic suspension between the swash plate and the valve body which means the pump has to come apart.Machines are like old dogs and old wives;if you ignore them they will turn around bite you!
whfh99
Member
I noticed that someone has put an aftermarket electric fuel pump on this machine, thus bypassing the original priming fuel pump. It looks like a little diaphragm pump with no pressure regulator. Could this pump be going south and not providing enough fuel volume for the engine to operate under load? If this is a fuel delivery issue, it's going to be easier for us to service than the hydraulics which I have zero experience with (so far anyway!)
joispoi
Senior Member
Put a pressure gauge on the fuel line right before the injector pump. That will tell you right away if it's a fuel delivery problem. A gauge should cost less than $15 at Napa.
whfh99
Member
How much fuel pressure should I see at that point? I assume pressure (PSI) will be a good measure of fuel volume as well, correct?
Richardjw~
Senior Member
out of interest how do you set a machine up if this is out of adjustment?