Re: Why does my diesel not rev when in gear?
Injector overhaul is a good place to start.. figure on $100 per... The stumbling might be a timing issue too, and that's usually an hour or two of good mechanic's time to set straight.
Difficulty starting can be other things... slow cranking, inadequate preheat (if appl) and poor compression. Battery health is one thing, long small gauge wire runs between batteries, panel and starter is another. Keeping a small heat source in the engine area will keep the oil warm and make for easier cranking esp in cool weather.
Not revving in gear is often prop related.. over pitched or really foul with marine growth...
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)