Good day to everyone. I'm here today on behalf of one of my machinery is not coroperating. Last week while an operator was running my komatsu pc360, it suddenly shut off. An LO3 code came up but he wasn't able to get the exact code the correlated to the LO3 or what symbol came up. Well now the code is no longer present and the machine just turns over. No smoke comes out no codes and it's beginning to stump me. I've read about the fuel rail pressure sensor causing the injection system to become "disabled" and not allowing starting of the engine. I've also read about the high pressure fuel pump actuator to be the problem. My problem is that the accuator has voltage that should lift the accuator to allow fuel to pass and also have fuel at the fuel rail. If anyone has ever ran into this problem before and can help it would be much appreciated. I don't have a service manual nor access to insite. I'm certified in networking of control modules but these are alittle different.
First check that the fuel supply to the engine is good.. Easiest way is to pump the hand primer until it's hard. It's located under the air filter on the top of the pre filter. When it's hard keep pumping it and you should hear a slight hiss from the engine area. Pretty well between the 2 hood latches on top of the machine. When your cranking it for say 20 seconds do you get a fault code.. This will be a red square with white letters reading ca 559 for example. Maybe for a quick check pull the oil filler cab and have a helper crank engine over just to ensure valves are turning.
The LO3 is a severity code and not the actual fault code. The severity of an O3, the computer has determined as a major, fix NOW, fault. You should be sble to scroll through the menu and find your fault code. It is more than likely an electrical issue.
I have purchased a service manual and found out how to get into the monitor through the "abnormality" section. The code I have is CA2249. Rail pressure very low. It also had in the memory a couple hours before a CA559 which is rail pressure low. I changed both filters on the machine and still no start. Tomorrow I will be looking further into rail relief valve, high pressure fuel pump, and injectors. Something is telling me is more than just a clogged filter since I have no smoke what so ever being produced. Just the motor turns over. Does anyone know if injectors are common on these engines to fail? Thanks again Nick
There should be a couple of fuses in the fuse panel for the engine elm, check those too. Check all the electrical wiring on the engine, there could be some wire chaffing that is setting off those codes.
That's engine ECM
In the service side of the monitor, go to pre-deifined monitoring. Find the page that says rail pressure and rail pressure command. While cranking see if the pressure goes to what the command says, or close to it.
How many hours on the hourmeter?
5124.8 hours. Will I have to clear the codes in the monitor?
If the pressure isn't close to the command would that mean lift pump or high pressure pump?
My rail pressure won't go about -365 psi comman says 5802 psi.
You can hear the lift pump when you turn the key on, it runs for 15 or 30 seconds before you start cranking. If fuel filters are full, that means the lift pump is good. Did you have water in fuel error before that problem happened. Anyway, the low rail pressure means fuel is leaking somewhere upstream the injectors or there is not enough fuel delivered by the pump. Try to find out a good mechanic with good experience on cummins engine
Odds are its got an injector stuck.. Best bet is to ethier get the dealer or get the injectoR blank off cap and blank the 6 injectors off one by one until you build rail pressure.. May be no harm in putting a gauge on the filter on the engine and make sure your getting around 2kg/cm while cranking. Normally you will get a bit of pressure on the rail pressure on monitor When lift pump is good.. Then pull off the delivery tube from the pump to the common rail and make sure it's putting out fuel...should be around 200cc in a min. If memory serves me right.
I can touch the lift pump and hear it working and feel it working. I'm going to block off injectors one by one to see if I build pressure. I will get a gauge to see the amount of pressure I have. Thanks again guys.
dont use a guage, use 36200 and 36400 monitoring codes.. thats your "rail pressure" and "rail pressure command", them injectors run around the 20k psi mark..
Yeah well my rail pressure is at -369 and the comman is 5802
I know this sounds like a stupid question but is that snap shot, while cranking?? cuz the rpms read 0..
I tired posting a video but it wouldn't post. The rpms during cranking get to about 120
It probably wont help w/ the major pressure drop you've got.. but.. Have you tried jumping the batteries to get the cranking rpms up just to see what the pressure is??
the cranking speed should be closer to the 170 mark... but even at 120 it should still build enough to bang..
Try to find out all the error codes, active or not active and post them
I've been charging the battery this morning and it's got 24v
It's got an active fuel rail pressure very low. First time it happened was 4749 hr and it happened again at 5124 hr
Call a mechanic, let him do leakage test and find out the cause of low rail pressure
Did you say -369. If its reading in negative the machine needs a new rail sensor or wiring harness checked.
Haven't posted in awhile but I have gotten the machine to start. One of the operators changed the high pressure fuel filter and must of gotten contaminants inside the line. Found a blockage in high pressure line from filter to cp3 pump. Changed the lines and also the rail pressure sensor. Fired right up
What would be the typical pressure
Bună tuturor. Am un Komatsu PC360 NLC 10 si am o problema la pornire. Începe doar cu spray-urile de pornire. După ce îl pornesc, funcționează în parametri normali. Când încerc să-l pornesc, presiunea în rampă nu crește mai mult de 56 de bari, ceea ce este insuficient pentru pornire. Am schimbat supapa de presiune pe rampa inalta si pompa de alimentare electrica. Când deschid prefiltrul, îl găsesc pe jumătate gol de combustibil. ma puteti ajuta va rog cu un sfat. Mulțumesc.