MEP 531a fuel pump issues

[FarmingSmallKubota]

I had posted on an old thread but was told to start a new one so here goes i have 3 mep 531a i bought with all having about 63 hours on each. Fuel lines were all rotted away on all 3 units and 1 unit had the fuel bowl, and oil drain plugs missing broken pull cord. The third unit was complete except fuel lines were missing and i could see the fuel shut off has all been messed with and factory wire was cut off that part. unit 1 replaced fuel lines and filters and oil, fired right up everything works great, Unit 2 Is now complete and borrowed pull start from unit 3. I can not get the unit to pump fuel, i removed the pump cleaned inspected. still nothing. I took the fuel pump out of unit 3 and tried that and still nothing, run switch is on. I will be pulling the from cover off to make sure timing is correct, and reset the valves, but just do not understand if i am missing something before i buy a new fuel pump.

 

[Dieselmeister]

I can not get the unit to pump fuel, i removed the pump cleaned inspected. still nothing.

Some thoughts,

Where are you not getting fuel? Have you disconnected the high pressure tubing at the pump outlet to see if you are getting fuel there? If not, are you getting fuel into the pump? Is the pump adjusted correctly so that it allows fuel into the pump when the lever is in the correct (run) position? Lastly, pull the pump, and check the cam under the pump, if it's moving. Does the pump have all the parts in it? I had one on a 531, that had the little poppet valve spring missing. While you have the pump out, fill the small inlet tube on the pump with diesel, and manually depress the plunger, to see if the pump will move the fuel. Have you checked the injector?

 

[FarmingSmallKubota]

So after some youtube watching today and better knowledge of how these pumps work i realized that the plunger was stuck on both pumps. I was able to get one pump unstuck and after many many air bleeding evens and a tired arm. the Generator came to life. Unfortunately the electric start does not work, and after powering up i found the contact switch does not work. Gauges show 120 v and 58hz and back of the switch shows 121.8v so we are doing a little better. I have soaked the other pump in Kroil and hope it will spring free but it was full of gunk and plunger is stuck

 

[FarmingSmallKubota]

So unit 3 fuel pump plunger was stuck to the point after soaking in carb cleaner and kroil and every little trick i could think of would not move. As a last resort i used a punch and hammer to force it down because had nothing to lose at this point. It worked and is free pumps really well. got everything back together and now the injector will not spray. Had that apart and cleaned it but still nothing. cleaned many other times and seems to be ok, but nothing so i put the injector in another machine and it worked fine. Can not get this unit to fire up. seems to have compression, and I know it has fuel so any help out there is appreciated.

 

[FarmingSmallKubota]

So a sad ending to this thread tonight i put a fuel pump in unit 3 from another unit and it fired right up, for about 30 seconds and then started knocking and slowed down. so at this point the motor is junk and the unit may get parted out. Unit 2 i posted a question in another thread about electrical, but no need for answers now because that unit i fired up as it was running great and then the engine ran out of control so probably will not post anymore about these units just stick them in a corner for parts for my 1 good running unit until i decide other wise. thanks for the replies