Spent the day tuning the old John deer 4440 we have. Last year, my brother sent the injection pump off to be rebuilt, professionally. Then complained all summer and winter that the thing felt down on power so it must be the engine needing rebuilt.
Nope, popped the injection cover off, when they rebuilt it, they didn’t turn in the fuel control screw far enough, barely 50 percent of stock setting. How it even ran is surprising. So I cranked it into the factory setting. Then decided the hell with it, let’s see what this does. Screwed it in two more turns. She’s a different animal now. She mean. Probably added 100 hp today, conservative guess, by the time you figure where it was at vs where it’s at now. Need to put my EGT gauge on and maybe turn it in some more. I know some guys turn it all the way in or even remove the plate but I don’t wanna go that radical...yet. With no intercooler, things will get hot quick