Komatsu PC220-6 Year Long Ongoing Power Problem PLEASE HELP

[Jake Erickson]

Anyone with experience please help. I’m at a loss right now, I have a pc220-6. Bought it with a power issue, was hoping it was simple and a year later I’m out of ideas. Rebuilt the pump, 1st time didn’t put in new pc valve, valve was bad and blew apart when adjusting, put in a new valve, general equipment tested and all pressures and functions were good. Side note, one pc valve was replaced not the second one… get it home run it and it works good for a few hours. Now it’ll work good for a few hours and than lose 80% of power, thought it was injectors, put 6 new ones in, new fuel line. Still very erratic in when it works or doesn’t. Can go hours with great power and then suddenly will fight it for a while, seems like if I throttle down for a minute and then back up it’ll work for a bit. Put on two sets of filters thinking that could be the cause and it hasn't changed the outcomes, I don't believe it's bad fuel because I drained it and have added new with stabilizer. Engine idles fine and runs good on full throttle, it's when you do a function that the power is gone. I have no clue what else to try. THANKS FOR ANY HELP

A few things I think it could be is an injector pump. But would an injector pump work great and then suddenly not and a minute later work great again?

Could that second PC valve be sticking?

Thanks for any and all ideas and help.

 

[John C.]

Which engine is in the machine, Komatsu or Cummins clone?

 

[Phantom970]

What’s it like with the fuel tank absolutely full?

check the fuel tank breather is working or not blocked

does it have a lift pump? Maybe it’s a dud

 

[LCA078]

Lots of threads here about floaters and other debris in the fuel that cause random fuel issues. There was a recent thread about a guy fishing a plastic sandwich bag out of his fuel tank that randomly blocked the fuel suction at the bottom of the tank.

I still can't comprehend why someone would willfully put crap like a plastic bag in a fuel tank. Takes some deliberate @ss-hat thinking to open a fuel cap, lift out the strainer, toss in the bag, and put everything back together.

 

[John C.]

I've seen the green movement wackos do all sorts of stuff like that. It's why locking fuel tank caps are a necessity. Stuff in fuel and hydraulic tanks, broken windows, broken gauge panels and cut up seats; moving all the survey and grade stakes on a construction site to filling milk jugs full of gasoline, hiking into a logging site and lighting machines on fire. It happens enough that the police treat it like a normal thing. Every wonder why your insurance bills keep going up?

 

[Delmer]

A few things I think it could be is an injector pump. But would an injector pump work great and then suddenly not and a minute later work great again?

YES, they do that all the time when the fuel supply is blocked like LCA said. Explains all of your symptoms. Fuel supply, not the injector pump itself.

 

[Jake Erickson]

Good information, that’s crazy that happens. To bad people have to be that way, they are disconnected with what keeps the world working. I was thinking of putting a small 12volt pump on the supply hose going to the filters to see if it helped

 

[Jake Erickson]

Which engine is in the machine, Komatsu or Cummins clone?

Cummins 5.9

 

[thepumpguysc]

Which injection pump..
inline or VE.
If it’s an inline with the supply pump is bolted to the side of the pump.. have u checked to see if it has the strainer in the banjo bolt in the inlet line.. it’ll be the line below the hand primer..
U haven’t said anything about looking in the fuel tank..

 

[Jake Erickson]

In line. I took the banjo bolt out and the strainer was clean, I reinstalled. I’ve drained a lot of fuel out of the tank and can’t see anything in there when I use a flashlight. The last two hours I ran it it worked flawlessly. I had rebooked the hose to the tank from the temporary 5 gallon can I had on the back. It was still acting up when I was sucking out of that prior to the last two hours. Going to hopefully find time this week to get out and run it some more. I’ll keep everyone posted. Thanks

 

[thepumpguysc]

Ok, good info..
When it starts acting up, try to use the hand primer to see if it clears up..
This will require a 2nd person in most cases..
IF it clears up, you’ll know it’s a fuel problem..air or a weak overflow valve..or maybe a weak supply pump .??
Force feeding it w the hp will tell the tale..(most cases)

 

[Phantom970]

Have you checked intake air supply to the turbo as well. Air filters, charge air cooler, turbo etc etc

 

[Delmer]

The inline pumps themselves are robust. The transfer pump and the start/run solenoid are weaknesses. The solenoid can be wired back if it's the external linkage type. There should be a port on the pump that you can hook up a gauge to, then read that when it's losing power.

 

[John C.]

The units with the Cummins/Komatsu clone engines have an in-line strainer that looks like an old in-line gas filter used on cars. Many people make the mistake of seeing it and going to the auto parts stores and ask for another filter. The gas filters are paper filters. The paper is cellulose and made to swell shut when water hits it. The in-line units made for diesel are brass strainers and made to only catch the big stuff. I have not found the banjo bolt strainers installed on the fuel pumps on Cummins motors.

Are you sure the problem is in the engine? The same thing can happen when the hydraulics over load the engine. Do you get any black smoke when the problem happens?

 

[anwat]

Anyone with experience please help. I’m at a loss right now, I have a pc220-6. Bought it with a power issue, was hoping it was simple and a year later I’m out of ideas. Rebuilt the pump, 1st time didn’t put in new pc valve, valve was bad and blew apart when adjusting, put in a new valve, general equipment tested and all pressures and functions were good. Side note, one pc valve was replaced not the second one… get it home run it and it works good for a few hours. Now it’ll work good for a few hours and than lose 80% of power, thought it was injectors, put 6 new ones in, new fuel line. Still very erratic in when it works or doesn’t. Can go hours with great power and then suddenly will fight it for a while, seems like if I throttle down for a minute and then back up it’ll work for a bit. Put on two sets of filters thinking that could be the cause and it hasn't changed the outcomes, I don't believe it's bad fuel because I drained it and have added new with stabilizer. Engine idles fine and runs good on full throttle, it's when you do a function that the power is gone. I have no clue what else to try. THANKS FOR ANY HELP

A few things I think it could be is an injector pump. But would an injector pump work great and then suddenly not and a minute later work great again?

Could that second PC valve be sticking?

Thanks for any and all ideas and help.

do you have engine stall problem under an adverse work load?,

 

[Eddiethewrench]

Anyone with experience please help. I’m at a loss right now, I have a pc220-6. Bought it with a power issue, was hoping it was simple and a year later I’m out of ideas. Rebuilt the pump, 1st time didn’t put in new pc valve, valve was bad and blew apart when adjusting, put in a new valve, general equipment tested and all pressures and functions were good. Side note, one pc valve was replaced not the second one… get it home run it and it works good for a few hours. Now it’ll work good for a few hours and than lose 80% of power, thought it was injectors, put 6 new ones in, new fuel line. Still very erratic in when it works or doesn’t. Can go hours with great power and then suddenly will fight it for a while, seems like if I throttle down for a minute and then back up it’ll work for a bit. Put on two sets of filters thinking that could be the cause and it hasn't changed the outcomes, I don't believe it's bad fuel because I drained it and have added new with stabilizer. Engine idles fine and runs good on full throttle, it's when you do a function that the power is gone. I have no clue what else to try. THANKS FOR ANY HELP

A few things I think it could be is an injector pump. But would an injector pump work great and then suddenly not and a minute later work great again?

Could that second PC valve be sticking?

Thanks for any and all ideas and help.

Electric volume fuel pump under tank,in line or built in to primary filter housing ... internal screen plugged .

 

[Jake Erickson]

The units with the Cummins/Komatsu clone engines have an in-line strainer that looks like an old in-line gas filter used on cars. Many people make the mistake of seeing it and going to the auto parts stores and ask for another filter. The gas filters are paper filters. The paper is cellulose and made to swell shut when water hits it. The in-line units made for diesel are brass strainers and made to only catch the big stuff. I have not found the banjo bolt strainers installed on the fuel pumps on Cummins motors.

Are you sure the problem is in the engine? The same thing can happen when the hydraulics over load the engine. Do you get any black smoke when the problem happens?

Right now I'm not sure. I pulled the injection pump off and sent it to Midland Diesel in Fargo as a last ditch effort. Craig said it's $1,900 to fix it has normal wear and tear except one cam lobe is wearing off and chewing up the roller. He said it's pretty common and can't see it being intermittent if it was the issue and would be all the time. If this doesn't fix it I'm starting to think it's something hydraulically. Either that second PC valve but all the mechanics say that shouldn't be the issue or possibly a wiring problem. But I get no codes on the display.

 

[Jake Erickson]

do you have engine stall problem under an adverse work load?,

No, it does it at random and under any and all functions when it's acting up. From moving either track to all boom,stick, bucket functions.

 

[Jake Erickson]

Electric volume fuel pump under tank,in line or built in to primary filter housing ... internal screen plugged .

I've checked the banjo screen right by the pump, I installed an inline fuel pump below the tank and it didn't help at all.

 

[Jake Erickson]

The units with the Cummins/Komatsu clone engines have an in-line strainer that looks like an old in-line gas filter used on cars. Many people make the mistake of seeing it and going to the auto parts stores and ask for another filter. The gas filters are paper filters. The paper is cellulose and made to swell shut when water hits it. The in-line units made for diesel are brass strainers and made to only catch the big stuff. I have not found the banjo bolt strainers installed on the fuel pumps on Cummins motors.

Are you sure the problem is in the engine? The same thing can happen when the hydraulics over load the engine. Do you get any black smoke when the problem happens?

I don't know, I was thinking it was. No black smoke. Would a bad or sticky PC valve cause it?