MF 383 Has No Power I Need Some Suggestions Please

Hello all. I have an MF 383 diesel it starts easy but will not throttle up. On startup it will throttle up for a second or two but then goes back to a lower idle, thats with the throttle wide open. I can leave it running for a while but it will eventually turn off. It will start right back up.
A little background. About a year ago i had similar situation. I ended up changing fuel filter it was full of crud and I pulled the fuel tank and cleaned it of algae/slime/water. It has been running great since and use to mow/disc no problem. A week ago drove it to the field no problem and as soon as the disc hit the dirt the tractor wanted to die. I quit early cause best gear was 3rd and the tractor would barely idle, as soon as disc was lifted the tractor would go wide open throttle. I changed fuel filter it looks ok very few hrs since i cleaned the tank. I pulled hose from pump to tank and have good flow but pushed some air back through tank anyway. No change. if i spray some fluid through air cleaner idle will increase dramatically. Also worked lever on lift pump while tractor is running and no change.
Anyone have any thoughts or ideas I could try. Thank You.

Hi, at the rear end of the main pump you will see the pipe coming
from the filter. Underneath the pipe Union is a large hexagon fitting.
Remove the pipe and slacken the large Union. There is a spring
under it so it will get easier to turn as you undo it. Place a cloth under
the pump so that you cannot lose any parts. Remove the large Union
and the spring. The plunger may come out with it. Inside the end of
the pump you will see a cylindrical strainer. Remove this using your
little finger if you can. It is very delicate. Using a tool of any sort may
damage it. The likelihood is that this strainer will be blocked. Over the
years I have had a number of tractors that would start ok but we’re
incapable of responding to the throttle. Use only low pressure if
cleaning with an airline. Use an aerosol such as WD40 or Dirtblaster
I think it’s called on your side of the pond. Carefully reassemble the
components. As an alternative you can remove the four bolts at the
end of the pump and remove the end plate. It can then be stripped on
the bench. Cleanliness is essential.
DavidP, South Wales

Ok thank you so much for the advice. i watched a video on taking it apart. I did as you said, took the screen out. It didnt look bad cleaned it anyway. Took the rest apart and cleaned. When i went to put it together i looked in the bottom of the end plate for a spring and didn't find it nor did i see one when I took apart. So now i'm not sure if it had one at all or somehow it fell out when I took the tube and plunger out. i'm gonna see if i can find one somewhere. I will post again when I get something done. So there I am. Thank you again.

Well found the missing spring in the dirt with a metal detector. Gonna put it together and get back with results.

So I got everything back together. Tractor starts easily runs for 5-10 second then shuts off. I can open up the throttle and it responds but shuts off. Its just not getting enough fuel seems to me. Any other ideas to try?

There have been posts about a changed design in fuel filters that were causing people headaches. I think the issues might have been with a NAPA filter.

I'm not sure your tractor even uses the affected filter. I think the problem might have been with using a gasket in the wrong place that would seal off the fuel flow.

(quoted from post at 10:04:51 08/29/20) There have been posts about a changed design in fuel filters that were causing people headaches. I think the issues might have been with a NAPA filter.

I'm not sure your tractor even uses the affected filter. I think the problem might have been with using a gasket in the wrong place that would seal off the fuel flow.

Click to expand...

If you are using a WIX 33196 or NAPA 3196, or other brand filter made by WIX of that style, Make sure the housing gasket did not get down inside the top of the element and cover the 4 outlet slots.

I will double check that seal, I'm pretty sure I put the seal up in the top filter housing. I will come with an update tomorrow afternoon after I check the filter seal and try a few other things. Thank you everyone again.

Have you checked the air filter?

Yes sir, I even pulled the secondary filter off for a little bit with the same results. Thank you.

Ok so here is the Sunday afternoon update. I changed lift pump back to the old original. I had bought a cheap one off the internet when I had issues that turned out to be water in the tank about a year ago. Ran air through the line from lift pump to filter housing. Changed fuel filter again. Tractor is working great now. I don't know what it was but that's ok, im good now. Thank you to everyone who viewed this thread and especially those who gave me some great ideas. I learned something from everyone who posted. Everyone have a great week.