User Manual

ManualsBrandsFarm Star ManualsEquipment720

Be sure your tractor is in good condition. Read all

the safety precautions and make sure all tractor

operators are familiar with the safety rules of

operation.

CAUTION!

INSTRUCTIONS

TRACTOR REQUIREMENTS

AND PREPA R ATION

NOTE: If your tractor lift arm spacing is 32”, place the

pull pins on the outside of the yoke legs as shown in the

diagram. If your tractor lift arm spacing is 26” or less,

then place the pull pins on the inner side of the yoke legs.

The pins are Category I (

” dia.). If your tractor is

Category II, then lift arm bushings are required to

properly fit the 1

” dia. Cat. II lift arm balls. (Bushings

not supplied.) Place the lift arms of your tractor over the

pull pins in the yoke and secure with linchpins (not

supplied).

Pin end of digger boom (Ref. #1) to tractor toplink

bracket. Raise boom by hand – check that it doesn’t hit

any part of toplink bracket (some tractors only). If

problem exists, change hole location and re-check.

Failure to check can result in boom damage. Cat. I

tractors need bushing. Connect yoke to boom with pin

(Ref. #12) and cotter pins.

NOTE: Always use adapter bushings when using

Category I pins on a Category II hitch. Trying to use Cat.

I pins in a Cat. II hitch without bushings will result in a

very sloppy fit and the post hole digger will be unstable.

NOTE: When attaching the yoke to the boom, use the

hole in the adjustment channel best suited for your

tractor. If you don’t know the best hole location, start with

the middle hole.

It is recommended that the gearbox output guard, the

gearbox input guard, and the PTO driveline be assem-

bled on the gearbox before the gearbox is fastened to the

boom. Place the gearbox upside down on the floor.

Install the formed metal gearbox output shield (Ref. #9)

on the gearbox. A socket with a long extension makes

this an easy installation.

Clean and check the input shaft of the gearbox. If any

nicks or dents have occurred in shipping, lightly file to

remove and make the shaft smooth.

Slide the plastic cone-shaped input guard on to the

input shaft of the gearbox.

Grease the input shaft of the gearbox before installing

the PTO shaft. This reduces the chance of the PTO shaft

yoke from galling to the input shaft if the shear pin should

break.

Slip the two telescoping ends of the PTO shaft together.

Spray WD-40 into the yoke and wipe. This should

remove some of the paint and make it easier to slide the

yoke onto the input shaft of the gearbox. Install the

unsplined end on the gearbox input shaft and bolt it in

place with the

” shear bolt (Ref. #13) and secure with

the lock washer and nut.

Unpack all the bundles and lay out various parts. Start

with the yoke (Ref. #2). Place the pull pins (Ref. #10)

through the holes in the legs of the yoke and secure with

nuts and lock washers.

ASSEMBLY AND MOUNTING

The Model 720 3-pt. mounted post hole digger will fit

most Category I, Category II and some larger Category 0

tractors equipped with a standard 3-pt. hitch.

NOTE: Some Category 0 tractors have very short lift

arms or

” diameter (Cat. 0) lift arm ball ends. These

tractors are not usually suitable for post hole digging

operation.

It is recommended that only tractors with wide front

axles be used with this implement. Tricycle front wheel

arrangements are inherently unstable and tractor roll-

over accidents are more likely to occur.

Check the tractor’s 3-pt. hydraulic lift system. It should

operate up and down smoothly and have enough power

to lift the dirt-loaded auger out of the hole. Refer to your

tractor operator’s manual or dealer for any adjustments

necessary to put the 3-pt. hydraulic lift system in good

working order. (I&T shop manuals will list most specifica-

tions and adjustment instructions - available from most

farm equipment dealers.)

Check the shield over the PTO stub shaft. Make sure it

is in good condition and bolted securely to the tractor.

Purchase a new shield if old shield is damaged or missing.

Tractor must be equipped with stabilizer bars,

adjustable sway chains, or sway blocks to keep the post

hole digger from swinging side to side.

Smaller size tractors may need front counter weights to

counter-balance the weight of the post hole digger and

the weight of the dirt on the auger.

NOTE: Low profile tractors generally can only use 30”

long augers instead of standard 42” long augers. Some

low profile Category 0 tractors should use the Model 300

Post Hole Digger.

It is recommended that the tractor be equipped with a

Rollover Protection System (ROPS) and a seat belt that

is used.

Never locate auger by putting hands on auger,

gearbox, or boom when there is any sign of rotation

on the driveline or auger or if the tractor is running.

W ARNING!

Do not shovel dirt away from a turning auger, as the

shovel can be caught by the auger and thrown. Do

not allow anyone to stand behind or to the side of an

operating auger. ALL persons should be at least 25

feet away.

CAUTION!

• In some types of soil, it may be necessary to hold back

against the auger screw suction by moving the

hydraulic control lever to “HOLD” or “RAISE” position

to keep the auger from screwing into the ground.

• NEVER use body weight to help the auger

penetrate the ground. When the ground is too

tough to penetrate with your cutting edges and point,

sharpen or replace them and try again. These are

replaceable parts and must be in good condition to

penetrate. (Optional Hydraulic Downpressure Kit is

available – order #706080.)

• If you have difficulty penetrating hard ground, refer to

Owner’s Manual Troubleshooting section for

suggestions.

• When the auger has been lowered about a foot or so

into the ground, raise the auger almost out of the hole

to clear the dirt, then drill deeper and raise the auger

again. Repeat this procedure until the desired hole

depth is reached.

• Do not shovel dirt away from a rotating auger as the

shovel can be caught and thrown by the auger.

• Disengage the power-take-off when traveling

between holes.

IT IS ESSENTIAL THAT EVERYONE INVOLVED IN

THE ASSEMBLY, OPERATION, TRANSPORT, MAIN-

TENANCE, AND STORAGE OF THIS EQUIPMENT BE

AWARE, CONCERNED, PRUDENT, AND PROPERLY

TRAINED IN SAFETY.

DIGGING A HOLE: Position the tractor so that the

auger point is placed where the hole is to be. Lower the

auger so that the point touches the ground. The point of

the auger should be approximately 3” back of center of

the gearbox. As the auger works into the ground, this

slight angle will straighten, due to the pivoting action of

the boom downward. If the auger has a side tilt, correct

with the lift arm adjustment on the tractor hitch.

If the auger tilts too far forward or to the rear, it may be

necessary to move the tractor slightly. Be careful not to

bend the auger.

The post hole digger auger is free-swinging, and care

should be taken while transporting the machine. DO

NOT transport the post hole digger while the PTO is

engaged as this could cause the universal joints of the

PTO driveline into a sharp operating angle and cause

failure of the driveline.

Engage the tractor PTO with the engine at idle (or below

1000 engine RPM). As the auger penetrates the ground,

lower the unit slowly with the 3-pt. hydraulic system. DO

NOT LET THE AUGER SCREW ITSELF INTO THE

GROUND! Auger must dig with the dirt breaking up and

being carried to the top by the auger flighting.

Once the hole is dug to the desired depth raise the

auger while rotating to bring the dirt out of the hole. To

get a clean hole, it is sometimes best to lower the auger

into the hole with the auger turning and then, when at the

bottom, stop the rotation and raise the auger while not

turning. This brings the dirt up with little left in the hole.

For best results, allow the digger to dig about half the

required depth, then lift it partially out of the hole to

remove dirt and then re-enter hole and finish to the

desired depth.

A Grade 2 (

” x 2

”) shear bolt is included with your

post hole digger. If the shear bolt shears, replace only

with a soft, Grade 2 shear bolt. DO NOT USE A HARD

SHEAR BOLT! Use of a hard shear bolt could result in

damage to the gearbox or other post hole digger parts

and voids any warranty.

Do not run the digger while transporting, as damage to

the PTO shaft could occur.

DO NOT LET THE DIGGER DIG SO DEEP THAT THE

PTO SHAFT IS RUNNING IN THE DIRT.

INSTRUCTIONS (continued)