lately i've been moving alot of dirt digging out terraces and my 440 seems to bog down when tracking and using loader controls at the same time but just at start up for a few minutes if you shut it off for five minutes and start it up it'll do the same thing even if its warmed up good i've only got 50 hrs on it since i changed the fuel filters i'm thinking it could be the lift pump but i'm looking for other ideas i'm going to service the filters first and see if it helps but it just seems odd to me that its just after start up thanks
A few fittings, a length of hose, and a vacuum/pressure gauge in the cab will tell you what's happening with the fuel pressure anywhere you want to check. After, and then before the lift pump if that's what you suspect. Or between the filter and injection pump, if it doesn't change much there, then you have other problems.
Its likely that the lift pump is failing. Lift pump should make 5-7psi of pressure. Another common issue is for the plastic fuel lines to crack, and suck in air into the fuel system.