Hello all, I am new to the fourm and a new equipment owner so please bare with me. I have a JD490E with 12,000 hrs that seems to be quite a good runner, but I've only had for about 40hrs. 4 times since Ive had the excavator I went to turn the machine off, keyed to off, and the engine dropped a hundred or so RPM and kept running. I cycled the key on/ off engine picked up rpm to normal keyed off and shut down normaly. Now the issue is, I am in a very remote location and just to get a tech there is the better part of $600 for travel, so Im trouble shooting this as far as I can with out swallowing that bullet, so I was Digging for about 4hrs normal operation, and the just enginge shut off while loading bucket with a slight belt squeek. No cough or sputter just like it was keyed off. Turned the key to restart and the engine cranks with no restart not a cough or any smoke. Steps taken include 1. replace fuel filter bleed entire fuel system 2. replace low pressure lift pum, old one seems slightly weak. 3. replace fuel shut off solinoid getting 24.4v when keyed to on and 14.4 ohms with no power to solnoid, old solinoid worked fine upon removal and bench test with adequate voltage and ohms. jumped the solnoid with a fused wire to good 24v still no start. 4. checked all fuses they are good I have been trouble shooting with Brandt and others for over a week now, to no solution except they want to come out to look $$$ again very remote ferry, boat ride, hike threw the bush. I have not checked relays, as everyone I have spoken with dosent think thats the issue, EC motor possible culprit in wrong position? Preformed EC motor bypass, I believe properly to no change! Fuel was blead to fill lift pump, filter, prime injection pump, prime fuel return, but fuel will not get to injectors! I can not feel the fuel shut off solonid click when keyed? but other relays are clicking batt realay and ec motor is attempting to move but dosent seem to do a full cycle, again techs talked to dont think this is an issue? Sight on injector pump Standayne DB4 - JD- RE45483 was removed and I can see the crank shaft turning in injector pump. But aparently on this DB4 that dosent mean the rotor is not seized. With the EC motor engaged to start which direction should it be to open, full front to rad or full pulled back toward hyd pump? This may help with where the EC motor is supposed to be on start up. The Crank position sensor has been mentioned, but again I dont have infinate $ to replace working parts just to rule them out! How do I test the crank position sensor voltage and ohm spec? What is your feed back? has any one had a sudden shutdown no restart like this with a JD490E with a 4045T. Thank you for all of your help
If you are getting full battery voltage to the fuel pump solenoid then it should not be a relay or a throttle motor problem. It should still start and run at an idle, but just to be sure remove the throttle cable at the pump and run the lever by hand. Did you hear the fuel pump solenoid click when you jumped it on the machine? If you can hear it click and are not getting fuel at the injectors it sounds like a pump problem.
excavator Thank you for the reply. No I can not feel the click of the solenoid when there is 24.4v to the fuel shut off. I talked with an fuel pump specialist and perhaps I installed the cap on to the pump wrong with out moving the plunger out of the way not allowing the fuel shut of to move. But that dosent explain the sudden shut down since the old fuel shut off was working when bench tested. I have leaking pilot controls in the cab and read that someone with a 200-2 or -3 had the oil leak short the wiring harness... I really hope that its not the pump! any tips for removal? I just ordered the JD gear puller for removing the gear from the front of the pump, just in case I have to remove it on the next trip out. Thanks again
The engine can be started w/ the top cover off.. just to diagnose the problem.. if its a solenoid.. Loosen AND remove the inj. lines from the back of the pump, just so the engine doesn't start.. Now, w/ the top cover removed.. crank the engine.. if fuel squirts out of the pump, you found the problem.. bad sol. or misinstalled top cover..
Ok thank you. So when the top cover is removed the linkage is in the open or run position? I will try this and let you know.
Before you touched anything and to prove that you didn't have a catastrophic engine failure , you should have given the engine a shot or two of quick start. If it ran then , you know it must be fuel related as if all the mechanical components of the engine are ok , all an engine needs to start is air and fuel