Difference between revisions of "Compact tractor"

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(thanks to David Osborne for writing almost all of this)
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==See Also==
==See Also==
* [http://groups.google.com/group/uk.d-i-y/browse_frm/thread/b71d91e0e9ddc6a5?hl=en# uk.d-i-y thread with more info]
* [http://www.hse.gov.uk/pubns/ais21.htm Flail safety]
* [http://www.hse.gov.uk/pubns/ais21.htm Flail safety]
* [http://www.compact-tractor-solutions.co.uk/ Loaders]
* [http://www.compact-tractor-solutions.co.uk/ Loaders]

Latest revision as of 22:36, 27 April 2009

An introduction to compact tractors.

Well, given that you're going to need your tractor serviced, it might be worth starting with local ag/grounds-care machinery dealers and talk to them about the products they sell/support.

The Rolls-Royce of compact tractors is Kubota (Japanese made). Their biggest tractor is less than 100hp, which is small-medium by ag tractor standards.

There's a lot of stuff coming out of China (e.g. Jinma) which is good value, but not best engineering/reliability.

Some of the main ag tractor companies have compact tractors on their line card, but often only a limited range or even just one model.

Tractors are fundamentally classified by the engine power. Compact tractors crossover large garden tractors and small agricultural tractors and have a power range of (say) 15hp to 50hp.

Implements are classified by their PTO power, i.e. the number of horsepower that must be available at the power-take-off on the tractor. The PTO power of a tractor is always somewhat less than the engine power.

Generally speaking, as the engine power goes up, so does the physical size of the tractor. It can be very misleading to research tractors on the web, because you don't get a sense of scale. You do need to go and see them for yourself - agricultural show season is starting, so go and visit a few over the summer.

So, basic features of tractors are:

2WD or 4WD - compact tractors are 2WD in the main.

Three-point-linkage - This is the mechanical/hydraulic system at the back which allows you to connect implements and raise/lower them.

PTO - Power take off - this is a drive shaft at the back, which is used to power implements.

There are a number of variations of PTO, viz the shaft diameter, number of splines on the shaft and shaft RPM. Standard speeds are 540 RPM and 1000 RPM.

You sometime see PTO speed of 540e or 1000e. The "e" stands for economy and means that there is extra gear in the drive train which reduces engine RPM (and therefore fuel consumption) at the expense of reduced available horsepower at the PTO.

One thing to watch out for on older tractors is whether the pto is "live" and runs independently of the tractor transmission clutch or not. Running a pto device that stops whenever you declutch, especially a mower, is not useful.

Aux Hydraulics. For powered implements such as hedge cutters, you will need auxiliary hydraulic circuits at the rear of the tractor. These are sometimes referred to as spools or spool valves and will usually be double-acting (see below).


Power loader. Your tractor will need mounting points and hydraulics for a power loader. Note that there are two sorts of hydraulics, single acting and double acting. Simple power loaders have single-acting hydraulics (power to raise the bucket, gravity to lower the bucket).

Double-acting hydraulics power the bucket down. Note that if you only have single-acting power-loader, you can only scrape along the ground surface, you can't "dig in" and you can't use the power loader to raise the front wheels (like a JCB does for stability).

Front weights. If you're having a heavy attachment on the back then you will need to make sure that you can have ballast weights on the front of the tractor. Otherwise, at the least the steering will be very light, and potentially, there will be a front-to-back overbalance risk.

ROPS. All new tractors must have a roll-over-protection system fitted by law. If you buy a used tractor for personal use, you don't have to have one, but if you let anybody else use the tractor, you're liable under H&S.

Mowing. There are loads of different ways to cut grass, including pasture topping, flail mowing, rotary, cylinder, etc. You will most likely find that your ride-on is the better product for mowing your lawns and that a compact tractor which is big enough to operate a hedging attachment is going to be too big for the lawns (unless you've got a large orchard or paddock which just needs rough-cutting).

I suspect that if you have significant hedge-cutting works to do then you will need to firstly find a hedging attachment which is up to the job and then find a tractor big enough to handle it.

The smallest Bomford hedge-cutter needs 15hp PTO, so you're into a 20-25HP tractor which is a minimum of £6k for a Jinma or £10k for a Kubota - plus £2k for the loader, another £1.5k for a hedge cutter, £750 for a mower.

Finally, hedge cutters use flails which will chew up and spit out the larger woody stuff in the hedge. Flail types. These can create a mess and flying debris, so you should make sure you have appropriate public liability insurance in place before you go hedge cutting.

See Also