4430 Low End Power

Got a new to me 4430 last year. Seems to bog out at low RPM's. I think it had a rebuild kit 2-3000 hrs ago. I spoke with a injector pump repairman who told me to check pressure at aneroid line. Tractor starts good but will lag below 1700-1800 RPM's it seems. Thoughts?

Welcome to one of the problems that the JD 4430 had. They did not have low end torque or good starting when cold either. Both issues where caused by lower mechanical compression and depending on the turbo boost to reach peak internal pressure. So yours is running like it should for the most part. If your going to pull a JD 4430 hard keep the RPMs up over 1800-1900. This 404 is not a lugging engine like the later 466 engines.

I have had JD 4430s that would work well on 95% of my ground but that one bank/hill would lug them below even what the quad range would down shift for them to lug through. So you would end up running in a gear lower, against the governor, just because of that one spot.

Aneroid is critical if it's still hooked up and working. As JD seller mentioned it won't be like the 466 engines. One thing that does help though is putting in a torque capsule from a 4450 governor and set it for more rack travel at lower speed, like the 4450 had.

I have 2 of these. I've never noticed the low end issue on the 4 post. Both tractors start good barely turning over. I do have to set the fuel advance by hand on the 4 post because it has the older mechanical fuel advance. I thought maybe I had a turbo or injector problem on the cabbed one. Thanks!

The responses from others are good, sound comments. We had a 4630, which was a 1976 model year. Over the course of the first 6 years of ownership, there were some trips into the dealership for repair and service work. New sleeves and pistons and later having the head planed and the valves all re-done made significant improvements in cold starting. The injection pump had the torque capsule change, which was also mentioned. I recently had a lot of work done on the engine of a 4640, resulting in a complete engine rebuild along with a rebuilt pump and injectors. The reason for all this work is another story for another day and post. The tractor generally acted and performed like any other 40 series Deere I had been around and operated. After all that work done to that engine, it has a lot more bottom end torque and is much more responsive over the entire operating band of the engine. Those who have operated it both before and after this work are very impressed by the degree of difference in how it runs. It is set at 180 horsepower. I suspect with all the work done on that engine, it is probably set up more like a 7.6 liter built in the last series or two when the 7.6 liter was used in Deere's tractors, and much less like the original 466 that came out with the 40 series, especially in the fuel controls.