185 Fuel Issue

I have a question. The other day i was digging with my 185 and about an hour and a half in it decided to lose RPMs and power to the point it could barely pull itself. Push the clutch in it regains the RPMs but if you let of the clutch it goes back to barely even pulling itself again, limped it home and let it sit till the next day ran fine for an hour or so again and did the same thing, came home and let sit for a couple hours and put it on the grain drill and it did the same thing after an hour in again. One time i got off and played with the fuel plunger and it seemed like it helped temporarily but i replaced that a couple years ago so dont know if thats the issue and need to replace or not also fuel filter is only 20 hrs old. Any thoughts on cause or fix ideas. Anything is helpful. Thank you 

Might have a plugged tank vent. See if you can get the fuel cap off when it does it. If it is pulling a vacuum take your air nozzle to the hole in the middle of the cap. Be aware that anything that is plugging it will come toward you.

Ted

Loosen screws on timing window so it leaks fuel and see if the "fixes" it. Bet a dollar the flex ring is shot. Know what you're doing before just pulling pump. Others have learned the hard way when they pulled a pump without setting timing first.

+1 to what cowkicker suggests. Flow from the tank outlet is an easy thing to check, and a common issue on any older tractor. I think every one of the last 4 or 5 tractors I've bought had crud partially (or fully) restricting the fuel outlet causing similar symptoms and requiring a tank cleaning. All the sludge/grime that's built up in these tanks over the past 50 years starts to strip off with the cleaning agents and alcohol additives in modern fuels. Wouldn't want to guarantee that's your problem. But definitely the first thing I'd check.

Yes.