This is the first in a series of articles that will look at ways to improve the throughput of your combine. We’ll start with the New Holland TR.

Peak performance of any combine depends on maximizing flow through a properly adjusted and maintained machine. This article focuses on how to get the most out of New Holland twin rotor combines. The twin rotor design includes the earliest variation (TR70) introduced in 1976 to the latest current models being the CR line of combines. What I put forward does not apply to each and every combine spanning a period of over 30 years, but does apply in general to most of these combines. Updates and design improvements are not applicable in the latest model combines.

Header and pickup

If you are picking up a swath, you need to have a high performance pickup in good condition. Two-roller belt type pickups are not high performance, but may be adequate on the older smaller combines. Swathmaster, Rake-up or other three-roller or four-roller/ double draper pickups are better performers. Belts and teeth should be in good condition.

If you are straight combining, it is important that the auger flighting is not worn excessively. The stripper bar behind the auger should also be in good shape and properly adjusted to prevent wrapping of the crop around the auger.

Feeder house

The main components that affect flow in the feeder house are the chain, sprockets and floor. The feeder chain should not be dragging on the floor (too loose) and should have good slats and not be stretched excessively. Sprockets should be in good condition to minimize wear and power requirements. Holes and tears in the feeder house floor restrict flow considerably.

Threshing and separating units

The most up-to-date rotor design is important for high performance. The solid body rotor introduced in the TR96 is the best rotor for TRs. Standard rotors (original design) and s-cubed rotors (second generation) can be updated to the solid body design. It may not be cost effective in the oldest combines, but they do increase capacity considerably.

Putting material through your combine is one thing. Separating all of the grain or seed out and getting that clean sample into the hopper is another issue. It is crucial that your concave and rotor group are in acceptable condition to handle the job and that they are properly adjusted. With most farmers growing crops with seed sizes varying from canola or mustard to peas or beans, it is also important to have the proper concave. Wide wire con-caves allow all sizes of seeds to pass through quickly enough to allow for maximum capacity, but filler plates and proper adjustments need to be maintained in order to get adequate threshing in some crops such as wheat and other cereals.

Rotor tunnels and vanes need to be in good condition. The rotor vanes direct the flow of threshed material rearward and into the discharge beater. If the vanes are worn excessively or damaged the flow of material is restricted.

The discharge beater should not be overly worn, and the pan under the beater should be straight. It is not uncommon to see NH combines with beater vanes that are worn or bent and pans that are pushed out in the middle. This occurs when there has been a wad or slug of material go through the machine.

Straw chopper

The straw chopper should be maintained in a state where it can operate efficiently. Straw choppers in good condition with sharp knives or hammers and stationary knives in good condition do a much better job of chopping straw and use less power. A worn chopper can consume up to 15 more horsepower to operate than one in good condition. That can add up to as much as 10 per cent of the power produced by the engine.


The last thing that can affect the performance of any combine is the condition and maintenance of the engine. Poor or dirty air and fuel filters can cause significant losses in power and productivity. Follow a good regular maintenance schedule and this will pay off in spades.

A lot of what I put forward here seems like common sense, but I am shocked to see the condition of many combines that come through our yard. I don’t think all operators knowingly run equipment in a state where they get much poorer results than possible. Instead, they are likely ignorant of the consequences of running a machine with one or many things out of condition or improperly adjusted and maintained. A few hours a year in maintenance and $1,000 or $2,000 in repairs has the potential to save tens of thousands of dollars in damaged grain, unthreshed grain, wasted fuel, lost time and premature machine wear or failure.

Charlie Smith owns Combine World in Allan, Sask. For feedback on this article or questions about combines in general, you can contact him at 1-800-667-4515 or [email protected]

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