Yes, it is an eec system. I believe built by Bosch. The large m tractors eec systems are NipondensoSo it's not a hydromechanical injection pump system? It's an EEC system?
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Yes, it is an eec system. I believe built by Bosch. The large m tractors eec systems are NipondensoSo it's not a hydromechanical injection pump system? It's an EEC system?
I agree. If the rail is being pressurized and adequate fuel is available at the high pressure pump, the problem is in the electronic components. Check all the connectors for clean contacts and good connections. These are the weak points in EEC systems. I don't know how timing is sensed but if there is a crankshaft position sensor(CPS)as on our Ford Powerstroke common rail system, these can be problematic leading to no starts and rundowns.No matter what ultimate fuel system a tractor has it isn't going to run unless it is getting fuel! checking the fuel delivery from the tank through the primary filter, lift pump and main filter as JerryMT says is still a good place to start!. If you ARE getting fuel through the bleeder on the main filter with the key on it is time for Diagmaster. There is just no other way of knowing where or whether those electrons are flowing.
I did have to replace a ECU on a L4060 just last fall so they DO sometimes fail! I don't remember the exact code but it did show a code. The grand L tractors show more information on the dash than the basic L's dolugbolt, I was trying to determine if the CAN bus was working to the dash computer, that would give us an idea if the ECU was at least working. If the glow plug light stays on after the dash does its self test, that would tell us that the ECU is talking to the dash computer, which is done over the CAN bus.
Well there are THREE fuel pumps! The electric pump, the fuel pump and the supply pump! Let us know which one if you can. ( supply pump is $3400 in Canada so you won't want to replace it very often!)Kubota service said it was the fuel pump. I dont see how because when ya turn the key on , fuel filled the water seperator quickly, and when i bled the fuel filter, fuel shot out of there too. I just hope it works after they put the pump on .
This may be an air bleed out of the fuel filter. It is there for under operation air bleeding. Can handle small leaks inherent to a shaky diesel. This configuration is same as my old Mercedes diesels. Common for this line to Tee up into the return line. It returns excessive air that rose to top in fuel filter to the tank. Also there should be a check valve and is probably at/inside the filter housing. Air can open the check valve and bleed out, but fuel from return line can not get back into the fuel filter .... it's flow to the tank is needed to move the air along.Addendum, most visible when you look at the tractor is a T in the tubes, one of which is a line off the fuel filter. It joins the overflow line from reserve tank that is going to fuel tank....
Follow the fuel hoses. The fuel goes from the electric pump, to the distributor, to the fuel cooler, to the feed pump, to the main fuel filter, to the supply pump, to the common rail, to the injectors. the injectors are supplied with constant high pressure fuel and inject when the ECU gives them a signal via the electrical connection on the top. the ECU determines the correct timing and amount to inject from inputs it gets from the crank sensor, the cam sensor, the throttle position sensor, the ambient air temp sensor, the coolant sensor, the mass air flow sensor and maybe a few more that I've forgotten about. Any one of those things will cause problems and may cause it not to start.OK so using Kubota's terminology:
Electromagnetic Pump = 12V Lift Pump
Feed Pump = ??
Supply Pump = Engine Driven Injector pump
How is the feed pump powered? Is it a gear driven pump also? How would you diagnose a bad feed pump? One would think that with the lift pump pushing and the injector pump sucking there would be no need for yet another pump?