Dexta Owners Manual (Part II)

Operation

STARTING THE ENGINE TO START THE ENGINE WHEN COLD
TO RESTART THE ENGINE WHEN WARM
TO STOP THE ENGINE
DRIVING THE TRACTOR TO CONTROL THE SPEED OF THE TRACTOR
POWER TAKE-OFF OPERATION
"LIVE" P.T.O. OPERATION
THE BELT PULLEY
OPERATING THE PULLEY
OPERATING THE HYDRAULICS
QUALITROL
LIGHT AND HEAVY DRAFT OPERATIONS
POSITION CONTROL
ADJUSTABLE CONTROL LEVER STOP
RAISING IMPLEMENTS TO THE TRANSPORT POSITION
AUXILIARY SERVICE CONTROL
DOUBLE ACTING RAM VALVE (Where Fitted)
"LIVE" HYDRAULICS
HYDRAULIC LIFT LINKAGE
CHECK CHAINS
LINKAGE DRAWBAR
STABILISER KIT
MAINTENANCE
THE FIRST 50 HOURS
FOR BETTER PERFORMANCE AND SAFE OPERATION

Operation

A skilful driver is one who knows how to get through a job of work quickly and efficiently by making the most of the equipment he uses.

The Dexta is designed for ease of control and incorporates well proven design features developed during 40 years of extensive experience in manufacturing and testing tractors. Your tractor, also incorporates many new design features, notably in the Hydraulic Power Lift which provides a choice of Qualitrol or Position Control assuring a first rate standard of work under all operating conditions.

This section describes in detail the function and method of using the tractor controls and also at the end of the section are tabulated a number of safety hints i.e. "DO'S AND DON'TS". Safety is largely a matter of common sense but we strongly recommend that the operator reads this hat carefully to understand why these points are stressed and what harm could result if they are overlooked.
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STARTING THE ENGINE

Before any attempt is made to start the engine, the lubrication and maintenance points, detailed on the Lubrication Chart must be carefully checked. Make a habit of attending to these points before starting the engine and, in particular, check the oil and water levels. Serious damage may result to the cylinder bores and bearings if the engine is run without adequate oil and water.

Under no circumstances should the engine be run without the air cleaner being fitted, or with a disconnected or loose governor suction pipe. If this is done, the action of the governor will be affected and the engine speed may increase to a dangerous level.

Make sure there is sufficient fuel in the tank. If air has entered the fuel lines due to the tractor having been left standing for some time, or if the tank has previously been run dry, then the engine will not start. In this case it will be necessary to bleed the fuel system.
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TO START THE ENGINE WHEN COLD

  1. Ensure that the fuel supply tap is turned on. The main supply is available when the supply tap is unscrewed two turns.
  2. Check that the main gear lever is in the neutral position.
  3. Ensure that the stop control on the control panel is pushed right in.
  4. Insert the main control key in the switch, turn to the right and check that both-warning lights become illuminated.
  5. Move the throttle lever in a clockwise direction to slightly more than the half open position.
  6. Press the induction primer button once only to inject a small quantity of fuel on to the heater plug and depress the heater button for forty seconds.
  7. Depress the clutch pedal fully and, with the heater button still depressed, operate the starter motor by pushing the starter control lever downwards. Pump the primer button two or three times as the engine is being turned over by the starter motor, when the engine should start.
  8. Release the starter control lever and the heater button immediately the moment the engine starts and adjust the engine speed by means of the throttle lever. If the engine does not start, wait thirty seconds and try again. Always ensure that all moving parts come to rest before attempting to re-engage the starter motor otherwise damage may occur.

If the engine does not start at the third attempt using this method, do not continue to operate the starter but investigate the cause by checking in conjunction with the fault finding chart.

Under no circumstances should the engine be run if the green oil pressure warning light comes on when the tractor is being operated; pull out the stop control immediately and investigate the cause of low oil pressure.

If the generator charging light remains illuminated when the engine is running this indicates that the battery is not being charged, and although this condition is not as serious as low oil pressure it should be investigated otherwise the battery may become fully discharged.
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TO RESTART THE ENGINE WHEN WARM

  1. Ensure that the stop control is pushed in and turn the main control key to the "on" position.
  2. Set the throttle lever approximately half open.
  3. Depress the clutch pedal and operate the starter motor control. Release this control immediately the moment the engine starts and move the throttle lever to obtain the required engine speed. If the engine fails to start adopt the procedure for normal cold starting as previously described.
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TO STOP THE ENGINE

  1. Depress the clutch pedal and place the main gear lever in neutral.
  2. Close the throttle lever to allow the engine to idle.
  3. Switch off the main control key. The switch should never be left on when the engine is stopped as the warning lights Will remain on and tend to discharge the battery.
  4. Pull out the engine stop control and hold it out until the engine has stopped turning over.
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DRIVING THE TRACTOR

  1. Start the engine as described above.
  2. Depress the clutch pedal fully. If the tractor is fitted with "Live" P.T.O. it is necessary only to depress the clutch pedal through half its movement, i.e. to the point where the increased resistance of the P.T.O. clutch will be just felt.
  3. Select the desired gear ratio by positioning the main and secondary gear levers as desired. If it is found that the gears will not mesh readily at the first attempt, return the gear lever to the neutral position, momentarily engage the clutch, depress the clutch and re-select the gear.
  4. Release the foot brake latch and move the throttle lever in a clockwise direction to obtain the desired engine speed.

Allow the clutch pedal to return slowly by gradually raising the foot until the tractor is set in motion, then remove the foot from the pedal entirely. If the tractor is to be driven at high speeds the brake pedals should be locked together.
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TO CONTROL THE SPEED OF THE TRACTOR
The speed of the engine is controlled by the throttle lever and for maximum efficiency it should be kept as nearly constant as possible. The maximum governed speed of the engine is 2,000 r.p.m. under full load, and a chart showing road speeds in the gears at various engine speeds is shown below.

It is most important to select the highest possible gear ratio to suit the load conditions. A little experience will soon show the most suitable gear to engage to suit the operating conditions and the beat speeds at which the engine will run. Do not permit the engine to "labour" when under load; bring tractor to rest, then select lower ratio.

NOTE: Should the oil pressure warning light become illuminated while the tractor is being operated, the engine should be stopped immediately and the cause investigated.

To stop the tractor apply the brakes evenly and depress the clutch as the tractor comes to rest to avoid stalling the engine. The brakes may be applied independently to assist in making tight turns but for fast road work the pedals should be locked together. To apply the parking brake when leaving the tractor first lock the pedals together, depress the pedals and move the locking latch rearwards to engage the pawl.
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POWER TAKE-OFF OPERATION
Before connecting up the drive shaft to operate equipment from the P.T.O. extension shaft it is necessary to remove the extension shaft cover, which is secured to the rear axle housing by two bolts. Refit the two bolts securely.

Install the coupling, ensuring that the guard is in position and the drive shaft is correctly aligned to the equipment.

To engage the drive to the P.T.O. start the engine, depress the clutch pedal fully and move the P.T.O. shifter rearwards. Release the clutch pedal gradually to ensure that the drive is taken up smoothly.
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"LIVE" P.T.O. OPERATION
The method of engaging the drive on tractors fitted with "Live" P.T.O. is the same as on standard tractors. The advantages of "Live" P.T.O. operation will be quickly apparent when the tractor is put to work. Continuous operation of the driven equipment is possible irrespective of the movement of the tractor.

Simply by depressing the clutch pedal through approximately half its travel the tractor can be halted for maneuvering or gear changing, without interrupting the drive to the P.T.O. To stop the P.T.O. it is necessary only to depress the clutch pedal through its full movement.

The hydraulics are also "Live", being driven through the P.T.O. clutch, but it is not necessary or desirable to engage the P.T.O. shifter.

It is possible to reset the clutch linkage so that when the pedal is fully depressed only the drive to the rear wheels is disconnected and the P.T.O. clutch continues to drive the P.T.O. shaft. This provision is intended mainly for hydraulic equipment and it should not be used otherwise unless there is adequate provision for disconnecting the drive in an emergency.
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THE BELT PULLEY
This attachment is available as an optional extra with the tractor or may be obtained for fitment through any Authorized Dealer. It is driven from the P.T.O. shaft and is secured by four bolts to the rear transmission housing. The engine to pulley gear reduction is 1.55 at a pulley speed of 1,290 r.p.m. at an engine speed of 2,000 r.p.m. This corresponds to a belt speed of 3,039 ft. per min. on the 9 inch diameter pulley. The pulley may be fitted off-set to the left or the right to obtain clockwise or anti-clockwise rotation of the pulley respectively (viewed from the left hand side of the tractor).

To fit the belt pulley unscrew the two P.T.O. shaft cover bolts and the four check chain bracket bolts and remove the cover and brackets. Refit the two cover bolts securely. Bolt the pulley in position, offset to the left or the right as required and tighten securely using the four special long bolts.
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OPERATING THE PULLEY
Ensure that the tractor is correctly aligned to the belt with the parking brake applied and ensure that the belt and the pulleys are free from grease. Start the engine, depress the clutch pedal and move the P.T.O. shifter lever rearward to the engaged position. Engage the clutch gradually and when it is seen that the belt is transmitting the drive correctly, speed up the engine as required.

NOTE: Never attempt to fit or adjust a belt in motion. It is also unwise to wear loose clothing when working near a belt.

Where the pulley is in constant use it is recommended that the oil level is checked daily and topped up if necessary with transmission oil to the level of the filler plug when the pulley is mounted off-set to either side.
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OPERATING THE HYDRAULICS
Outstanding features of the hydraulics are the simplicity of operation coupled with the choice of either Qualitrol or Position Control. In either system one main control lever situated on the right hand side of the tractor and adjacent to the driving seat is used to set the working depth (or height) and to raise or lower the implement. A second lever immediately in front of the main control lever selects whichever system the operator considers best suited to the job in hand.

The hydraulic pump is in continuous operation whenever the clutch is engaged. Where a "Live" P.T.O. is fitted, however, the transmission clutch may be disengaged without affecting the operation of the pump. It is not therefore necessary to engage the P.T.O. selector lever in order to operate the hydraulics.
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QUALITROL
Where ground contour and soil conditions constantly change or when surface conditions are such that loss of wheel grip would normally be expected, Qualitrol enables work to be completed which would be impossible without such a system. To engage Qualitrol, place the selector lever in the downward position (see Fig. 7) and move the main control lever down the quadrant until the implement reaches the desired working depth. This depth may be changed at any time by repositioning the lever, i.e. the lower the lever is placed in the quadrant the greater the working depth obtained, and vice versa. The implement will now operate at this depth as long as the draft remains constant but if a heavy patch of soil or an obstruction is encountered the hydraulic system will respond by raising the implement. At the same time this action transfers weight to the rear wheels, giving increased wheel grip to assist the tractor until such time as the draft decreases when the implement will be automatically repositioned at its former depth. Such corrections enable the tractor to maintain a steady of work without loss of wheel.
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Fig. 7. The Hydraulic Controls

LIGHT AND HEAVY DRAFT OPERATIONS
To ensure sensitive Qualitrol operation for both light an heavy draft operations a two-hole rocker is fitted to the transmission housing. For heavy draft operation such a ploughing, connect the upper pin to the lower of the two holes (Fig. 8) and for light draft operation such as cultivating, make the connection at the top hole.
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Fig. 8. Two-hole rocker.

POSITION CONTROL
This control enables the operator to set an implement at any required position relative to the tractor and this will then automatically be maintained irrespective of changes in soil resistance. It is particularly suitable for maintaining a high quality of work when cultivating or ploughing ground which is reasonably level. To operate under Position Control, place the selector lever horizontally and then position the main control lever within the quadrant to give the required depth (or height) to the implement. As with Qualitrol the lower the control lever is placed in the quadrant the lower the implement will operate.
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ADJUSTABLE CONTROL LEVER STOP
Once the desired working depth (or height) has been obtained the adjustable stopscrew in the quadrant may be set to contact the main control lever so that after any particular cycle of operations the implement may be returned to the same working position simply by moving the control lever on to the stop.

The use of this stop does not in any way interfere with the Qualitrol operation which will continue to make adjustments to the working depth above and below the mean depth as set by the stop, in order to maintain continuous work at a steady pace. When the stop is used in conjunction with Position Control a rapid and yet completely accurate depth setting is assured each time the impiement is returned into work after turning on the headlands.
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RAISING IMPLEMENTS TO THE TRANSPORT POSITION
Lift the control lever until it abuts the nut on the small hexagonal screw at the top of the quadrant. The implement will then be lifted to the fully raised position where it will remain until the main control lever is again moved down the quadrant.

When operating in Qualitrol any intermediate position may be obtained by holding the control lever against the upper stop until the desired height is reached and then moving it downwards off the stop a short distance. If movement is comparatively small it is sufficient to enable the internal control linkage to find a neutral position and a little practice will soon familiarise the operator with this position for the control lever.

Under Position Control the height of the implement is directly governed by the position of the lever in the quadrant and it is therefore possible to raise to any desired intermediate position for transport simply by moving the control lever.

When driving with an implement in the raised position do not travel at speed, particularly over rough ground, to avoid imposing shocks on the hydraulics.
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AUXILIARY SERVICE CONTROL
This unit (Fig. 7) is provided to permit the use of hydraulic power to operate remote cylinders on such equipment as loaders or trailers. When the control knob is pulled out oil is diverted from the ram cylinder to the auxiliary equipment. Raising and lowering is controlled in the usual manner by moving the main control lever within the quadrant.

The lift arms and auxiliaries cannot be operated together and there is no neutral position of the control.

It is recommended that auxiliary equipment is operated with the selector lever in the Qualitrol position, i.e. downward.

CAUTION

Except when the linkage drawbar is fitted the following precautions should be observed before moving the auxiliary control from ram cylinder feed to auxiliary service feed, or vice versa.

Ensure that:
-the lift arms are in the fully raised position.
-the main control lever is against the fixed stop at the top of the quadrant.
-all equipment is at rest.

To operate auxiliary equipment first pull the auxiliary service control knob into the outer position then move the main control lever past the fixed stop at the top of the quadrant to feed oil to, or down from the stop to exhaust oil from, the equipment. It is important that the recommendations of the equipment manufacturer regarding operation are strictly observed.

Remote cylinders will be operated by oil initially drawn from the rear transmission housing and, although the quantity of oil available is sufficient for normal operation with approved equipment, it may be necessary to top up the oil level if a number of auxiliaries are operated simultaneously. Remember that any auxiliary which is disconnected when extended represents a loss to the rear transmission oil level and this must be replaced by adding a corresponding additional quantity of oil to the rear transmission. All hoses should be cleaned before connecting up, and the open ends of all unions should be covered with dust caps when not in use.
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DOUBLE ACTING RAM VALVE (Where Fitted)
The double acting ram valve (D.A.R. valve) when fitted, replaces the Auxiliary Service Control on the hydraulic power lift cover. Two pipes may be fitted leading from the D.A.R. valve to a mounting bracket at the rear of the transmission housing where they are readily accessible for connecting up the coupling pipes to rear mounted or trailed equipment.

When the D.A.R. control lever is pushed from the neutral position, the hydraulic lift cylinder is isolated from the hydraulic pump and the oil is delivered under pressure by a pipe to the double acting ram. At the same time, the oil displaced from the opposite side of the ram piston is returned through the second pipe to the D.A.R. valve and exhausted into the transmission housing.

When the D.A.R. control lever is moved through neutral to the opposite position the oil flow is reversed, and the pipe previously used to supply oil to the ram under pressure becomes the oil return pipe and vice versa. The lever is spring loaded in the neutral position and must be held forward or rearwards as required to operate the ram. When released it returns itself to the neutral position when normal operation of the lift arms is possible.

The double acting ram can be operated irrespective of the position of the main control lever in its quadrant as the D.A.R. lever overrides the hydraulic lift operation. The hydraulic lift cannot therefore be raised at the same time that the D.A.R. lever is used but a lowering action can, however, be carried out simultaneously.

The speed at which oil is supplied to the D.A.R. can be controlled by adjusting the Flow Control Knob set in the top of the D.A.R. valve cover. This control can be moved between two stops marked F. and S. which indicate the positions for fast and slow operation respectively. The correct position of the Flow Control Knob will depend on the type and weight of the equipment being used, and will be affected also by the operating conditions and the engine speed. It is most important that the recommendations of the Implement Manufacturer regarding speed of operation are strictly observed.

Where quick release couplings are employed, as on the extension pipes to the rear of the tractor, the dust caps must always be fitted when the couplings are disconnected.

The D.A.R. valve may be used to operate a single acting ram by making the connection to either of the delivery ports and blanking of the non-used port with a standard self-sealing coupling. If equipment other than that officially approved by Ford Motor Company Ltd. is to be used steps must be taken to ensure that some form of restriction is incorporated in the equipment to prevent a too rapid return of oil from the operating cylinder.
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"LIVE" HYDRAULICS
If your choice of tractor has been one with "Live" power take-off ("Live" P.T.O.) then the hydraulics will also be "Live" and may still be operated independently of forward motion of the tractor. This is a decided advantage where lifting operations are required to be continuous even though gear changing is in progress and the main transmission clutch disengaged.

Just as with the "Live" P.T.O., depression of the clutch pedal for approximately half its travel will disconnect the drive to the rear wheels but will not stop the operation of the hydraulic pump. On the other hand if an emergency arises whereby both the tractor and the hydraulics require to be stopped, pushing the clutch pedal through its full range of travel will disconnect the engine drive from both the transmission and the hydraulic pump.
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HYDRAULIC LIFT LINKAGE
The tractor is fitted with Category 1 linkage and may be used with a wide variety of implements. A leveling box is provided on the right hand lifting rod to control the level of the implement in work, the lever being easily reached from the driver's seat.

The lower links are fitted with ball joints at both ends and the front ends are mounted on pins on the rear transmission housing. These ball joints must not be lubricated in any way as the oil or grease would serve only to collect abrasive dust in the joints and cause increased wear. The upper link is similarly ball jointed at both ends and is adjustable for length to control the fore and aft level of the implement by turning the centre turnbuckle. The turnbuckle lock nut should always be tightened after adjustment has been made. The standard length between centres is 25 in. (63.5 cm).
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CHECK CHAINS
Check chains are fitted between the lower links and securing brackets on the centre of the rear transmission housing. Their function is to prevent excessive lateral float of implements in the raised position. The check chain brackets should be fitted to the axle housing with the chain connection offset to the top.
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LINKAGE DRAWBAR
This is available through your Authorized Dealer and is used in conjunction with trailed equipment. The complete kit consists of a drawbar which fits between the lower links and two support stays. The support stays fitted between the ends of the drawbar and a pin which passes through the upper link rocker fulcrum are adjustable for length so that the drawbar may be set at any required height within the adjustment range of 11 to 22 in. (29.2-57.1 cm.).

If the linkage drawbar is being used with the auxiliary service control in its innermost position, or whenever a D.A.R. valve is fitted in conjunction with the linkage drawbar, the hydraulic main control lever must not be raised, otherwise the support stays will be damaged. The safety chain attached to the right hand support stay may be secured to the main control lever quadrant to lock the lever in the "down" position when these conditions exist.

If, however, a single acting ram is to be operated from the auxiliary service plate whilst the linkage drawbar is in use, as on the FR Trailed Disc Harrow, the auxiliary service must be moved to the outer position and the hydraulic main control lever used to divert oil to and from the ram. Providing the auxiliary service control knob is in the outer position there is no necessity to use the safety chain and the hydraulic main control lever may be moved at will.
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STABILISER KIT
A stabilizer kit is available to minimize side float of the lower links when certain implements such as a linkage mounted mower are in use. The kit consists of two bars which are secured between the ends of the drawbar and special brackets bolted to the rear axle housings.
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MAINTENANCE
The hydraulic unit is precision built and is accurately adjusted before the tractor leaves the factory. The only maintenance work required is to ensure that the rear transmission oil level is checked regularly and topped up as required, and to grease the leveling box weekly.

If the hydraulic power lift is not in regular use the lift should be operated periodically to maintain a film of oil on the working parts to prevent corrosion. Consult your Authorized Dealer should it be necessary to carry out any repairs or adjustments.
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THE FIRST 50 HOURS
The working parts of the engine and transmission of the Dexta are manufactured to a high quality finish giving a precision fit between mating parts. During the first few working hours these parts are subjected to a polishing action and finally acquire a very hard smooth surface which has a high resistance to wear.

This process of forming a hard skin on bearings, cylinder bores and gear teeth, etc., is usually referred to as "running in" and is essential to the subsequent performance of the tractor. The driver must therefore understand what is meant by this term and use the tractor accordingly during this short period.

The main thing to remember during the first fifty hours' work is to operate the tractor under a light load and at moderate engine speeds. Avoid overloading the engine and running at high engine speeds. The load should gradually be increased during this period and after fifty hours you will be able to begin putting the tractor on to heavier work with confidence. It is important to get the engine warmed up quickly and to maintain an even working temperature. Once the engine is started, do not allow it to idle but put it under a light load straight away to assist a rapid warm up.

Particular attention must be paid to the lubrication. Check the engine oil level frequently and also the radiator water level to avoid overheating. After the first day's work, remove the radiator filler cap, open the drain taps on the radiator and cylinder block and flush the system through thoroughly. Allow the engine to cool off however before pouring cold water into the radiator.

It will be found that the wheel discs will bed-in on the hubs and the wheel nuts should be checked for tightness after the first day's work. Repeat this check as necessary over the first few days until no further movement can be obtained on the wheel nuts.

After the first 25 hours the tractor should be thoroughly checked over and serviced as elsewhere in this manual.
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FOR BETTER PERFORMANCE AND SAFE OPERATION

DO -carry out the Daily Maintenance Tasks every day without fail.

DO -keep the air cleaner clean and the oil at the correct level.

DO -ensure that the correct grade of approved lubricating oil is used and that it is replenished and changed at the recommended intervals.

DO -fit new sealing rings when filter elements are renewed.

DO -watch the warning lights and temperature gauge and investigate any abnormality.

DO -keep the radiator filled with clean water. In cold weather use anti-freeze; drain the system only in an emergency and refill before starting the engine. TAKE THE WATER TO THE TRACTOR-NOT THE TRACTOR TO THE WATER.

DO-keep all fuel in clean storage and use a filter when filling the tractor tank.

DO -read all the running-in instructions.

DO -attend to minor adjustments and repairs as soon as the necessity is apparent. When in doubt consult your Authorized Dealer.

DON'T -run the engine without the air cleaner or with the governor pipe disconnected otherwise the engine speed may increase rapidly and cause damage.

DON'T -run the tractor downhill out of gear or with the clutch pedal depressed, or travel at high speed without previously locking the brake pedals together.

DON'T -engage the clutch suddenly or drive with your foot resting on the clutch pedal.

DON'T -allow the tractor to run out of fuel as it will then be necessary to bleed the fuel system.

DON'T -interfere with the fuel injection pump; if the seal is broken your Warranty becomes void.

DON'T -allow the engine to idle for long periods or excessive carbon will be formed on the injectors; the engine starts easily and such idling is wasteful.

DON'T -run the engine if it is not "firing" on all cylinders.

DON'T -drive the tractor at speed with implements in the raised position, particularly over rough ground.

DON'T -run the tractor with the P.T.O. engaged unless it is in use.

DON'T -remove the radiator filler cap when the engine is near boiling point.

DON'T -attempt high speed turns by using the steering brakes.

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END OF PART II

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