SECOND-HAND MAKES SENSE
SECOND-HAND MAKES SENSE
A high output mower
conditioner need not cost
the earth providing the right
second-hand model can be
found. Greenlands service
manager Bill Foulkes
shows Geoff Ashcroft what
to look for
GEARING up the silage or hay making operation with a high capacity trailed mower conditioner can be a cheap option if set about the right way.
The vast number of models that have come onto the market in recent years makes buying second-hand an attractive proposition – providing the right machine can be found for the right price.
One option could be Greenlands Vicon-badged GMT2800. The trailed mower conditioner was introduced six years ago and offers a 2.8m (9.1ft) cutting width using a disc-type cutter bar and a swivel hitch. Output, with 120hp doing the driving, is said to be about 3.2ha/hour (8 acres).
Unless the machine has fallen into the hands of a contractor, its unlikely to have been "round the clock" so to speak, with many machines finding their way through 80-120ha (200-300 acres) annually. Our example machine, a tidy four-year-old Vicon GMT2800 has worked its way across 404ha (1000 acres) to date, and could be expected to fetch about 50% of its £15,000 new price.
"The biggest problem with these machines," explains Bill Foulkes, "is that people tend to over-power them in search of that little bit of extra output and it can cause premature wear on the drive line."
With this in mind, a close inspection of our potential purchase starts at the front, with a look inside the pto tubes. Exces-sive use of horsepower will show up as badly worn profiles in the pto tubes.
Main gearbox on the swivel hitch is robust, though any oil leaks could be the result of a blocked breather. While looking around the gearbox, check the swivel ball socket below the gearbox/drawbar assembly – though not prone to breaking, they do need regular greasing.
Concealed within the drawbar is the mowers main power transmission belt – a wide power band, it twists drive through 90í providing an input to a second gearbox from where bed and conditioner drives are taken.
"Its tension is crucial to belt life and is kept in check by belville springs and a floating collar at the front end of the drawbar. Replacement belt cost is £368 so look closely," he advises.
Secondary gearbox is a trouble-free item and providing theres oil still inside, is good for the life of the machine. From here, a shaft drive drops straight down into the mower bed.
"Vibration is the biggest factor in shortening the life of a mower, so a thorough inspection of the cutter bar is essential," he says. "In the first instance, all the disc heads with three blades a disc need to be in place. A build up of grass and dirt beneath the discs can eventually cause them to break off."
"A closer look will reveal any missing deflector plates from each disc and with an operating speed of 3000rpm, anything missing from the rotating assembly will simply cause the mower bed to fail."
"Its also important to check the amount of free play between each cutting disc and the timing of the discs, to make sure they all follow a uniform pattern of alignment and do not foul each other."
"Blades are cheap at £1.10 each, discs are a little dearer at £60 each, while a replacement mower bed runs into the thousands," he warns.
"Oil level too, is critical. Too much and the mower consumes horsepower with a vengeance; too little and it will wear out prematurely."
Checking the level is achieved by placing a 30cm (12in) block under the right-hand end of the mower bed, then lowering the machine to the floor. This puts the bed at the correct angle to check the oil level. The level plug is also magnetic so any internal gear or bearing problems will show up.
Below the bed, wear skids are fitted for its protection and an abused machine will have little remaining on the wear skids, if anything at all. Expect to pay £72 a skid to replace. Badly worn skids could be the result of a defective float system – it should be adjustable, not seized.
Above and behind the mower bed is steel-tine equipped conditioning rotor. Like the mower bed, it too needs to run in perfect balance in order to maintain some longevity. "Conditioner drive is via four vee-belts. If worn out, expect to pay just over £20 a belt, though theyre not parts that need replacing on an annual basis," says Mr Foulkes.
Finally, run the mower and check everything works and theres no unusual noises coming from the machine. This should be the deciding factor on whether or not to reach for the cheque book.
"If everything runs except the mower bed, then a small cardan shaft between the secondary gearbox and bed is likely to have snapped – its replacement cost is £361 and although a rare occurrence, it is likely to have been caused by bad realignment of components following a major rebuild."n
The Vicon GMT2800 disc mower conditioner from Greenland. The trailed, 2.8m wide machine uses swivel hitch design for tight headland turns.
A good wear skid will have plenty of material left on it, like this one which has done four seasons work.
Look closely for the three deflector plates on each cutting disc. If missing, these will contribute to an early demise of the main cutter bed through vibration.
Conditioner drive belts are £20 each should they need replacing…
…while main power band inside the drawbar costs £368. Tension is everything.