Used Grain Drill Inspection Checklist: What to Check Before You Buy

Buying used · 8 min read

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A used grain drill is a deceptively simple machine: a seed box, a metering system, and a row of openers rolling across the field. But a drill that meters unevenly or plants at uneven depth costs you all season, and the problems hide where you have to look for them on purpose — worn disc openers, tired metering flutes, seed tubes with cracks you can only find by hand. Here is what to check before you buy.

The seed box: rust, lids, and leftover seed

Start at the top. Open every lid on the seed box and look inside. Grain drills hold seed against steel, and seed holds moisture — so the box is where rust starts. Look for rust along the bottom seams, around the metering openings, and anywhere seed has caked and sat. Surface rust on the walls is one thing; rust that has eaten through the bottom or around the meter openings is another, because it changes how seed flows.

Check the lids themselves: they should close flat and seal. Bent, warped, or missing lids let rain into the box, and water in the box usually reaches the metering system too. A lid that will not stay shut in the field will dump seed on the road.

While the box is open, look at what is left inside. Old seed caked in the corners tells you the drill was put away dirty, and a drill put away dirty is a drill whose metering parts were never cleaned either. Ask what seed it ran last — small grains, soybeans, and cover crop mixes all wear and pack differently.

Metering: flutes, cups, and feed cups

The metering system is the heart of a drill, and it is where a bad buy hides. On a fluted-feed drill, pull the metering covers and look at the flutes. Worn flutes lose their sharp edges and meter unevenly — some rows get more seed, some get less, and the stand comes up patchy. Turn the metering shaft by hand and watch every flute turn with it.

On cup-feed or air drills, check each metering unit the same way: it should turn smoothly, with no cracked housings and no seed packed solid inside. Seed buildup hardened into a crust behind the meters means the drill sat with seed in it, and hardened seed jams meters.

If the drill has a variable-rate or half-width shutoff, engage and disengage it and confirm every section actually stops and starts. A shutoff that sticks half-open plants double on headlands and leaves skips where it should be planting.

Disc openers: diameter, sharpness, and bearings

Disc openers do the actual planting work, and they wear in ways that are easy to measure. Measure disc diameter across several rows. Openers wear down with use, and once a disc drops below its working diameter it cannot reach planting depth consistently — shallow rows in hard ground, deeper rows in soft ground, and a stand that comes up uneven.

Check the cutting edge. A good opener edge is round and sharp enough to cut residue; a worn edge is rounded over, nicked, or chipped, and it pushes residue into the furrow instead of cutting through it. That residue — hairpinning — keeps seed from reaching soil contact, and poor seed-to-soil contact is the top cause of a spotty stand from a used drill.

Spin every disc by hand and feel the bearings. A disc bearing should spin smooth and quiet. Grinding, catching, or wobble means the bearing is done, and a wobbling disc cuts a crooked furrow. Check the scraper on each opener too — scrapers keep soil from building up on the disc, and a missing or worn scraper lets mud pack the opener until it stops turning altogether.

Depth control and gauge wheels

A drill plants at the depth its gauge wheels set, so check the whole depth system. Gauge wheels should be round, not flat-spotted, and their tires should be intact — a gauge wheel with a chunk missing rides lower on that row and plants it deeper than its neighbors. Rock each gauge wheel side to side and check for play in the arm and pivot; sloppy pivots let depth wander as the drill bounces.

Work the depth adjustment through its full range on several rows. Adjustments that are seized, stripped, or missing their stops mean you cannot set depth evenly across the drill — and uneven depth is uneven emergence. If the drill has press wheels, check them the same way: round, turning freely, with intact tires and no bent arms.

Seed tubes and delivery

Follow the seed path from meter to furrow on every row. On a conventional drill, seed drops through tubes; on an air drill, it travels through hoses to the opener. Either way, check for cracks, kinks, and wear holes. A cracked tube leaks seed before it reaches the furrow, and the row comes up thin — a problem you will not see until emergence, weeks after you bought the machine.

On air drills, check the fan and air system. The fan should spin freely with no bent blades, and hoses should be whole, with no collapsed sections or loose clamps. Run the fan if you can and feel for even airflow at the openers — a row with weak airflow gets less seed, and a hose that blows off mid-field leaves a blank row across the whole pass.

Frame, toolbar, and hitch

Walk the full frame and toolbar looking for cracks, especially at welds where the toolbar meets the hitch and where wing sections fold. Grain drills flex constantly, and cracks start at welds and bolt holes. Check wing-fold hinges and locking pins — wings that will not lock solid in field position will bounce and plant unevenly, and wings that will not fold will not make it down the road.

Check the hitch and jack stand for wear in the hitch hole and cracks at the tongue. Check the transport wheels and tires: drills sit most of the year, so check sidewalls for dry-rot cracking and look at the date codes.

Drives, chains, and ground drive

Most drills are ground-driven, so the drive system is simple — and simple to overlook. Follow the drive from the ground wheel to the metering shaft: check the drive wheel tire for wear and flat spots, since a slipping drive wheel meters less seed than the setting says. Check every chain for stretch, stiff links, and missing rollers, and check the sprockets for hooked or worn teeth. A stretched chain jumps under load and meters in surges.

Grease every fitting you can find and watch for fittings that will not take grease — a seized fitting means that bearing has not been greased in a long time. Spin the ground wheel and confirm the metering shaft turns with it, smoothly, across the full width of the drill.

Hydraulics, markers, and electronics

If the drill has hydraulic lift or fold, cycle every function and watch for smooth movement with no jerking or drifting down under its own weight. Check hoses for chafing, cracking, and weeping at the fittings, and check the cylinders for rod scoring and seal leaks.

Check the row markers if fitted — they should extend, lock, and fold without binding, and the marker discs should spin. On drills with a monitor, acre counter, or blockage sensors, power it up and confirm it reads. Walk the harness for chafing where it crosses the frame and folds. Blockage sensors that never alarm are worse than none at all, because they give false confidence.

The calibration check: the test that tells the truth

If the seller will let you, run a calibration check — it is the single most revealing test on a used drill. Set the drill to a known rate, turn the drive wheel a set number of revolutions, and catch the seed from every row separately. Weigh each row's catch and compare. Rows that meter far above or below the average have a metering, tube, or drive problem, and you have found it before you paid for it rather than after emergence.

Records to ask for

Ask for maintenance records: opener and disc replacements, metering parts replaced, bearing work, and any frame repairs. Ask what crops it planted, how many acres a year it covered, and how it was stored — inside and cleaned beats outside with seed left in the box. Ask whether the calibration has been checked recently and whether the drill comes with its manual and any spare metering parts.

A used grain drill rewards a careful inspection more than almost any other machine, because its problems show up as a bad stand weeks after the sale. Work through the box, the meters, the openers, and the depth system row by row, run the calibration check if you can, and you will know what you are buying before the first seed goes in the ground.