I have a Cat 299D2 that shut down and would not refire. After it sits 10 mins it restarts for a couple seconds and then dies. We did end up doing a turbo on it but I believe that it is unrelated to the actual problem. We cleaned everything up after the turbo went out and have the same starting issues. The Desired and Actual rail pressure are very close (Actual is about 30PSI above desired) and it still wont fire. When it initially start and runs for 5-10 seconds it runs great. Then it sputters and will not fire. Maybe leaky injectors? Thanks for any help! Tyler
There are a load of Logged Diagnostic Codes/Events on the PSR you attached, but nothing is Active. Have you tried erasing everything in each of the ECMs then try a few starts and see what comes back.? Also have you done any sort of checks, repairs, maintenance, etc on the low pressure fuel system from the tank right as far as the HPFP.?
I will try erasing all of the codes in each of the ECMs. I did do the fuel filter and then blew back through the tank with air from that filter as we used to have 28 of these and now we are down to 4 left. So many of these started plugging at the tank pickup. Ill check my low side pressure. Is it supposed to be around 12psi?
Not sure TBH. Maybe someone else knows. If you have had so many of these machines do you happen to have a spare engine ECM kicking around.? That particular component does not have a stellar reputation for reliability. There was a Cat mini-ex with the same engine model as your CTL on here recently with the exact same start-run-stop symptoms that after going round in circles with the fuel system turned out to be a failing/failed ECM With 28 machines have you ever come across engine wiring harness issues such as wires breaking inside harnesses.?
We did swap an ECM and it did the same thing. I have done about a dozen engine harnesses on these 299D2s and several aftertreament harnesses. The dealer did the harnesses and Aftertreatment ECM on this a couple years ago. With downtime being expensive it was more reasonable to just replace the harness rather than find a break most of the time but I do know alot of the breaks seemed to happen by the taller harness holder back towards the rear of the engine below and behind the fuel rail. This harness does not do anything when i do the wiggle test and seems to be reading everything alright.
Did any codes come back after you cleared them all? Does it keep running if you disconnect the rail pressure sensor? Do both engine RPM sensor readings match in ET while cranking? I'd also be looking for what's causing the 1239-1 fuel leakage codes... You have the newer transfer pump, should be 15 psi dead headed, 12 psi running with a clean filter, 1.5 lpm. Pressure reduces to about 1psi after the plastic tee (relief valve) in the supply line to the HPFP. Worth checking for a broken spring in the HPFP PCV valve, has been covered a few times on these forums. Do an Air Systems Motor Valve test in ET, it tells us if the intake throttle and EGR valves are working properly. It doesn't tell us if the throttle butterfly has come loose or the actuator itself is broken/blocking air flow. Need to visibly look at them during the test to check that. Horrible on a 3.8, but easy if you have a borescope. Has it ran normally at all since replacing the turbo? I do wonder if it's over fueling. Might be time to pull injectors and borescope cylinders. Another horrible job on this engine. All food for thought before throwing parts at it. Has the fuel tank got fuel in it?
Just out of curiosity, have you successfully swapped engine ECMs between machines with these 3.8 Kubota's in the past? Did you have to play Kubota software?
I have gotten them to start on a different machines ECM. I did it to test for a bad ECM that was giving me a crank - no start symptom. I didn't run it any longer than needed to verify.
That’s good to know, thanks.