45Farm Contractor & Large Scale Farmer June 2014

The value of a used plough will relate as much to its suitability for its intended role as its overall condition. New or used, the wrong plough will remain the wrong plough, no matter what it cost

Continued over the page

buying a plough

It is all too easy to make a few general assumptions when considering buying a plough, be it new or used. One

stumbling block is to buy according to current tractor capacity, only to find a change a few seasons on sees the key ploughing tractor’s basics, such as horsepower, rear linkage lift capacity and size of tyres change, only to find one or all subsequently do not suit the plough.

Those ploughing a known area of land will have the advantage of knowing predominant soil types and the anticipated area to be ploughed, but contractors may also have to factor in a wider range of soils. There may be the need to work with a press, work at varied ploughing widths to suit changing conditions. Most variable width ploughs can have furrow widths set from 30cm to 45cm, some offering a stepless setting or fixed 5 cm (2") manually adjusted steps.

Now consider the point to point and under beam clearance. Used ploughs come

to market for a host of reasons, with poor performance in trashy conditions rating among a common reason for an upgrade. You cannot wave a magic wand over any plough to increase these clearances so check you know exactly what you are buying.

When it comes to plough bodies, manufacturers will tend to have settled upon a key set that suit UK conditions, solid board mouldboards suitable for working at 12.7 to 27.9cm depths at all furrow widths proving a good general-purpose body for most soils. Bodies that will plough at depths of 17.8 to 35.6cm remain the favoured choice for deeper work prior to root crops and for use in heavier soils.

Longer bodies designed to throw the soil further from the landside for a wider furrow bottom suit tractors on wide tyres running in the furrow bottom. Now increasingly common, these longer bodies may increase draft by around 5%, a point

you may need to consider if the tractor is at it limits power wise. Slatted / finger bodies remain popular regionally and should be regarded in the same way as a solid body offering the same furrow width and depth settings.

The final basic pointer is to consider the ploughs duty strength. The headstock and beam are built to suit a specific power bracket. This is pretty obvious but it can be tempting to snap up a used plough that may be just on the wrong side of the capacity you are after. Promising yourself you will not overwork the plough soon gets forgotten when the weather is closing in and it is then that problems may arise. The flip is that over specifying can see too heavy a plough sitting behind a tractor that struggles to cope during tricky headland turns.

What to look for on a used buyJob one is to mount the plough to allow it to be raised, turned and various settings checked. This will include electronic controls that may be fitted such as front furrow width adjustment. Rams that have not moved in a while can also have issues when first used again, particularly if the chrome on the ram or a seal has suffered.

A plough that tends to ‘fall’ over too quickly past the butterfly position during reversal may not have been set up correctly from new, so it helps if you know what to look for. Worn turnover

When considering a used plough, you need to put in as much care at ensuring it is of the right specification as you would a new one. The best buy is always the most appropriate tool for the job.

Farm Contractor & Large Scale Farmer June 201446

pivots are rare on a cared for plough, so be wary if there is an issue on a plough that is not that old.

With the plough raised or removed from the tractor, look for backlash in the turnover axle. On some ploughs, the ‘O’ ring seal can fail, allowing dirt in. This does not wear the axle itself so much but more the headstock tube ends. If this is the case, shims can be fitted on some models to cure the problem

The cross shaft should be central to the headstock, a change to suit variable width wheels at some stage possibly leading to the shaft not being set correctly. If the plough produces an uneven finish it may not have been set evenly, leading to an uneven front furrow width. This is a good place to check.

A lot will depend upon plough make and model too. Some have a shaft that can locate in one of three holes, the rear top standard position providing the closest coupling and the best position for most tractors. As some tractors have a protruding valve block, the cross shaft can be located to increase the clearance as the plough is raised. A small detail but one that may need checking on a used purchase.

On some headstocks there will be a choice of fixed of slotted top link holes, the latter suiting the now pretty much universal lower link sensing, but some still plough as if the tractor has top link sensing and use the fixed hole. This can lead to possible wear and uneven ploughing.

Front furrow widths are increasingly adjusted hydraulically rather than by winding out a turnbuckle. A frame alignment ram may also be fitted, again allowing the plough to be adjusted to suit a specific tractor.

All bolts securing the headstock and frame must be really tight. It can be worth checking to see if any obviously new bolts are of the same grade as obvious originals. If not, ask a few questions.

Soil packers tend to drop in and out of fashion but where fitted the packer arm needs to be given the once over if it is to be used.

legs and frameBody leg design tends to be pretty much standard across models within a range of ploughs, but the way they are mounted does vary between manufacturers. Ploughs with fixed legs and shear bolt protection need a really good check, elongated bolt holes often arising when the shear bolt works loose. Shear bolts should obviously all be checked to ensure they are of the correct type, a high torque 10.9 grade having the number stamped or cast into the bolt head. The key is to have the correct ‘brittle’ strength to shear cleanly. Too soft a bolt, and it will tend to deform rather than shear. If the legs are out of alignment, check for partially sheared bolts.

Traction, as opposed to shear, bolts are used on some ploughs. A key claimed advantage of the traction bolt is that it tends to be easier to remove if the leg trips as the nut or nuts strip off. Traction bolts can be tightened without compromising their ability to trip

A visual check along the bodies is typically enough to pick up any discrepancies in body alignment, the same view along the skimmers also helping to show up any problems. Some bodies can be adjusted and re-aligned but be wary if the plough is clearly out of adjustment. Also remember it is really difficult to check a plough is ‘true’ when the key landside and share reference points are worn. A re-metalled plough is always easier to check.

On frames with a drop off body attached, check it is bolted on tightly and that the alignment is correct. The joint has to take a good deal of stress, particularly in transport. Manufacturers may suggest the bolts are tightened with a torque wrench, typically to around 60 kg/m.

Depth wheelCheck the wheel locks and look for wear and tear on the tyre. New rubber can be costly. Bashed wheels can have distorted rims, causing issues in transport to include uneven tyre wear. Tubeless implement tyres must have a good seal to the rim to prevent pressure loss. Remember implement tyres will have a transport speed rating. Do not expect a low inflation pressure tyre to be suitable for high transport speeds. Specific plough transport wheels are an option of some ploughs to include those made by Kuhn.

bodies and wearing partsIt is not unusual to see the front bodies

showing more wear than the rest, and this can normally be traced back to the plough having been set to produce a deep front furrow to create enough soil to fill in the ‘hole’ left by wide tractor tyres. Although it is acceptable to perhaps lean the plough over slightly to create more soil, working deeper is not the answer. The key is to actually reduce the front furrow width; dropping from 16" to 15" can do the trick.

It is perfectly acceptable to swap more worn front bodies with ones from the middle, to extend the life of the mouldboards; light damage and fractures need not necessarily mean these items are scrap either. On a used plough, however, cost in replacing everything as a complete set. It is all too easy to under estimate how much time and money it can take to re-metal a worn plough and it can take a long time to make sure everything is correctly aligned.

Looking over the skimmers, check for wear on the support saddle. These will wear if the skimmers themselves have been run worn. Sword share knives are increasingly specified in place of a rear disc, and for most users they make a sound choice; a rear disc will produce a neater furrow wall, but it will be obliterated by a wide tractor tyre.

With regard to wearing parts, spurious components may well have been fitted. In terms of wear, the metal used in better quality non-OEM parts has improved, but the actual fit can be poor. Poor fitting can increase draft and wear in the longer term, OEM metal typically paying for itself. Do not forget to match the fasteners to the parts if they are not supplied. The wrong type of bolt can cause expensive damage.

Summary It is not difficult to assess the condition of a used plough. The trick is to choose the right specification and to know how much it will cost to renew worn metal. As a rough guide, assume you will need to spend £200 per body in common wearing parts and allow £30 per body to pay for fitting them.

Also do your homework. Check the price of the used plough against a new one, and do not forget to factor in possible deals and finance packages. Consider the value of any plough you may be trading in, this sometimes making it more economical to buy a used plough through a dealer than trying to source and sell a plough privately. Avoid an impulse buy and remember a bargain buy is only that if it turns out to be a useful purchase. As we said at the outset, the wrong plough will always be the wrong plough, regardless of what you paid for it.

With grateful thanks to Matt Grew and the team at Kuhn UK.

Buying a Plough

47Farm Contractor & Large Scale Farmer June 2014

Buying a PloughIn the following table, outline specs of

core Kuhn five-furrow ploughs are listed. This helps to illustrate how much variation there is between just one manufacturer, let alone when comparing different makes

and models. The weights of the ploughs are not listed as this will vary dependent upon body type, auto-reset and other options.

As a guide, however, the lightest Kuhn

five-furrow Multi-Master 113 plough will weigh around 1,370kg, on land Multi-Master 183 units coming in at 2,273kg.

Kuhn Master reversible ploughs outline specifications, five furrow modelsModel Beam box Max power Variable width settings* Under beam/point to point

dimensions (mm) rating (kW/hp) (in/cm) clearance *(mm)Multi-Master 113 120x120 110/120 14,16,18/35,40,45 700/900 Vari-Master 113 120x120 132/160 12 to 19/30-48 700/960 Multi-Master 123 120x120 + triangle 129/175 14,16,18/35,40,45 750/900 Vari-Master 123 120x120 + triangle 129/175 12 to 20/30 to 50 750/900 Multi-Master 153 150x150 + triangle 166/225 14,16,18/35,40,45 800/102 Vari-Master 153 150x150 + triangle 166/225 12 to 20/30 to 50 800/102 Multi-Master 183 180x180 + triangle 202/275 14,16,18,20/35,40,45,50 800/960 Vari-Master 183 180x180 + triangle 202/275 12 to 19/30-48 800/960

The specifications outlined above show the importance of knowing how different five-furrow reversible ploughs within the range offered by a manufacturer differ in terms of power rating and clearances. When buying new or used, selecting the correct specification is critical. This listed specifications are for guidance only and do not include all related Kuhn plough models.

*Dependent upon model and version, variable width options available to cover wider settings of up to 20 inches / 500mm. Under beam and point to point clearances can also vary dependent upon specific model selected. ALWAYS CHECK ON A USED BUY!

VARI MASTER 123

Strength and adaptability

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Strength and adaptability

be strong, be KUHNforage harvesting I livestock husbandry I arable I landscape maintenance

Innovation in plough safetyNON-STOP HYDRAULIC (NSH)

• Plough leg safety system with rapid release onimpact with obstacle and quick return to work.

• Share-point release pressure easily adjustable from 600 – 1,300kg, and can be increased (with MAXIBAR) to 2,500kg and adjusted on the move from the cab (VARIBAR).

• Exceptional vertical (60cm) and lateral (20cm each side) clearance.

• All moving parts integrated into the beam.

VARI-MASTER ploughs are renowned for their robust one-pieceheadstock and large diameter turnover shaft and are adaptable due to user-friendly offsetting and angling facilities.The variable working width (30 – 45cm) is fully integrated into theplough beam, and all pivot points are bushed, to ensure greatdurability. Side-mounted triangular reinforcement adds further strength to the main beam where most needed.The VARI-MASTER 123 range includes models with 3 – 5 bodies, with a choice of traction bolt protection or non-stop hydraulic auto-reset protection.www.kuhn.co.uk

Varimaster 190x130Farm Contractor_Layout 1 10/06/2014 16:53 Page 1

Farm Contractor & Large Scale Farmer June 201448

Longer L body (left) is now the most popular Kuhn plough body type and will allow in-furrow plough with tyres that exceed 650 width. Note body extension in centre, this helping fold a difficult furrow. L slatted body (right) increasingly common in Eastern counties, but retrofit furrow widener on VP slatted body to its left can help and is an easy retrofit.

Buying a Plough

Auto rest bodies now favoured by new buyers, despite adding to plough’s overall weight. There are numerous designs on offer, the Kuhn system pivoting up and having adjustable trip setting.

Plough duty strength increases in line with the maximum power listed by the manufacturer. Kuhn triangulates the beam of its Multi-Master 123 and up, increasing the beam box section too. A plough should be matched to the power of the tractor.

A wide range of adjustment is

offered on the bodies of Kuhn

ploughs to allow for any slight

misalignment. When looking over a

used plough it can be difficult to spot

issues, the more so if you are looking

over a plough with worn wearing parts.

Hydraulic variable width is increasingly common on ‘larger’ ploughs, but now the alignment that was carried out using a turn buckle is increasingly controlled hydraulically too. The aim is to make it easier to make adjustments on the move.

Depth wheels can work hard and need to be properly inspected on a used plough. If the wheels doubles up for transport duties consider the tyre fitted and its suitability for high road speeds.

49Farm Contractor & Large Scale Farmer June 2014

Buying a Plough

Headstock design has advanced in the past few years to offer not only improved durability but also enable improved routing of pipework as pictured. Auto-reset ploughs need looking over carefully, pressurising the system sometimes enabling operators to ‘over work’ the system.

Trash burial is a key to good commercial ploughing, the setting and design of skimmer having a big impact upon plough performance. Standard ‘large’ ZXL skimmers are the most common type fitted to Kuhn ploughs in the UK, the larger ZRL design suiting more challenging conditions to include burying maize stalks.

Traction bolts, in this case fitted with two nuts, are an alternative to shear bolts. When looking over a used plough try removing the shear bolts and checking the holes have not elongated through wear.

Bolting to the rear of the plough, the Kuhn transport wheel has a degree of suspension to help cushion the ride. The tyre is designed for road use, and is not intended to be used as a plough depth wheel.

Small refinements to more recent ploughs go beyond electronic controls for the front furrow width and alignment. Available as a retrofit, the in-line filters Kuhn offers as an option for its turnover ram hoses are designed to help reduce problems with contamination.

Most manual vari-width systems are left once set, but varying the width to suit different soils and conditions can have a noticeable impact upon both productivity and the quality of work. Width settings can also be adjusted to suit different conditions. On a used plough, try adjusting the plough.