yanmar ym2000

[curtis cothran]

i am new to the forum and will probably get lost. i recently acquired a green YM2000 tractor that has been setting for several years. the previous owner parked it and when he went to start it it would not start. it set for several years before i bought it. cleaned the fuel tank, installed new lines, filter etc... i am getting a good supply of fuel to the injector pump but nothing out when cranking. fuel tank is full. everything i have looked at is clean in the engine. any advice would be appreciated.

 

[winston1]

Welcome to the forum. :welcome: Wouldn't suprise me if the rack on the fuel pump is stuck or even the plungers. I would pull the inspection plate and move the throttle checking to see the rack is moving. Note refernence #21 on this parts drawing. Yanmar Tractor Parts: INJECTOR_PUMP

 

[curtis cothran]

i have had the pump out and this part would not move, should i be able to move it by hand?

 

[normde2001]

i have had the pump out and this part would not move, should i be able to move it by hand?

It should drop of it's own weight, end-to-end just by tilting the pump.

 

[curtis cothran]

It should drop of it's own weight, end-to-end just by tilting the pump.

I believe that you have identified the problem. It does not move. What could have made it stick. The inside of the pump looks new. I can take a drift punch and the handle of a screwdriver and it will move. I have sprayed id down with WD40 with no results. Any suggestions

 

[winston1]

Time and rust made it stick. If continued working it with lubricants applied does not work then nothing left but to take it apart. They are a bit complicated and if you don't feel confident you might want to consider and injector pump shop. You do not want to change any settings on the internals.

Here is what a new one is worth. Yanmar Tractor Parts INJECTOR PUMP - NEW! - OUT OF STOCK - WE CAN REBUILD YOURS Well, looks like they are out of stock, might want to inquire about the rebuild.

Any knowledge of the condition of the tractor before being set up?

 

[curtis cothran]

Thanks I have taken it down as far as it will come with the drive pins in. It looks like that one of the center rods (I assume that this is the volume adjuster) is rusted or gummy.

 

[normde2001]

Unless you are a good mechanic I recommend having it rebuilt. There are timing marks that seem to give a lot of guys fits on reassembly.

 

[curtis cothran]

I have gone as far as my abilities can take me. If it does not loosen up in the next day or 2 that is exactly what i will do.
thanks

 

[California]

Good plan.

99% of the stuff on these Yanmars is user-maintainable, designed that way, but overhauling an injector pump is simply best left to a specialist. There's calibration needed that you can't do without test equipment, and probably special tools needed too.

I was amused to find for overhauling injectors on these 70's designs, the manual specifies to scrape the orifice only with 'a wooden stick and mutton tallow'. How's that for Old School.

I just figured after 35 years service I would replace with new instead of searching for mutton tallow. Then what I received was NOS in 70's packaging. (faded lime green, not red). So, Old School anyway.