User Manual

ManualsBrandsFarm Star ManualsEquipment720

On the implement end of the PTO shaft there is a hole

in the yoke just forward of the

” shear bolt (see Figure

A). This hole is for the

” diameter x 1

” long roll pin

(#2504011). When this roll pin is driven in this hole, the

center of the roll pin engages into the groove on the front

of the gearbox input shaft. This prevents the PTO

assembly from coming off if the

” shear bolt should

shear. When replacing the shear bolt, use only a soft,

Grade 2 shear bolt. DO NOT use a hard bolt!

Attach the gearbox (Ref. #5) to the boom using the

gearbox hitch pin (Ref. #6) and secure it with the two

cotter pins (Ref. #7). The gearbox should be placed so

that the large shaft is pointing toward the ground and the

small shaft is pointing toward the tractor.

NOTE: The gearbox is shipped WITHOUT lubricant, so

it will be necessary to fill it before use. With the gearbox

in a level position, fill to the side inspection hole with a

good 90 wt. gear lubricant. Check often and add lubricant

if necessary.

Clean tractor PTO stub shaft and the inside of the

splined driveline yoke. Pull the spring loaded ring from

the end of the yoke and slip the splined driveline yoke on

the splined PTO shaft of your tractor. Release the spring

loaded ring and push the yoke on until it locks in place.

(The spring loaded ring holds locking balls that lock the

tractor end of the PTO driveline on the tractor PTO shaft.)

Make certain the tractor PTO shield is in good condition

and securely fastened onto the tractor.

Slowly raise and lower the digger without the auger on.

Watch to see that the PTO driveline and/or shields do not

separate or get into a bind. Check to see if gearbox end

will lower to the ground. If it will not go all the way down,

then either change the hole location between the yoke

and boom or check to see if the PTO shaft is bottoming.

NOTE: If your tractor PTO shaft has a 1

” spline, it will

be necessary to obtain a 1

” to 1

” sleeve spline

adapter. If tractor is equipped with a 1

” to 1

” spline

adapter extension, it may be necessary to cut the PTO

shaft off in length. Check this before putting the auger on

or digging a hole. To check, raise and lower the post hole

digger with the tractor BEFORE putting the auger on.

NOTE: The use of a PTO extension could require that

the PTO driveline be shortened a considerable amount.

If this is done, the driveline halves may separate when

the post hole digger is raised to transport position.

If the PTO driveline needs to be shorter, remove the

driveline from the tractor and digger gearbox. Lower the

digger (without the auger on) until the input shaft of the

gearbox is in line with the PTO stub shaft of the tractor.

(This should be the shortest distance required for the

driveline.)

Pull the two telescoping halves of the PTO driveline

apart. Connect the tractor end to the tractor and the gear-

box end to the digger gearbox (but NOT with the two

halves together).

Hold the two driveline sections parallel to each other

and mark each end as to how much too long they are.

Then raise the digger to transport position and again

hold the two driveline halves parallel to each other and

check for a minimum of 6” (15 cm) overlap. If driveline

has less than 6” overlap, do not use. Contact your dealer.

If at least 6” of overlap is provided, then proceed in

cutting the driveline.

Figure 1

1. If driveline must be cut to a shorter length, clamp

driveline in a well padded vise to prevent damage to

the shield. Cut off shield where marked. Using cut-off

section of shield as a guide, cut shaft the same

amount. (Figure 2)

Figure 2

INSTRUCTIONS (continued)

Do not install a longer bolt or other longer fastener!

A protruding fastener is more likely to grab loose

clothing and can cause serious injury or death.

W ARNING!

2. Repeat the procedure to the other driveline half.

Remove all burrs and cuttings.

3. Apply multi-purpose grease to inside of outer (female)

driveline section. Assemble driveline and install on

tractor and digger. Pull on each driveline section to be

sure yokes lock into place. Make certain driveline

shielding is in place and in good condition.

4. Carefully raise and lower the digger and check to be

sure the PTO assembly does not jam. If it does, cut

equal amounts from each half of the PTO assembly.

5. Check the swinging drawbar of the tractor and make

sure the PTO driveline assembly will not contact. The

swinging drawbar can be moved forward on some

tractors or it can be removed.

NOTICE!

PTO drivelines on model 720 post hole diggers

manufactured after October 1, 2000, do not have a

dimple protrusion on the square tube half of the

driveline or a groove in the 15/16” square shaft.

This means that it is possible to assemble the two

halves incorrectly.

Failure to properly align the end yokes may result

in excessive vibration.

Always make sure the end yokes are correctly

aligned when sliding the driveline halves back

together. See figure 3.

NOTE: Use stabilizer bars, adjustable sway chains,

or sway blocks on your tractor lift arms to keep the

post hole digger from swinging side to side. Adjust

as tightly as practical for best performance.

Slide the auger over the large shaft of the gearbox and

secure it with the two bolts, lockwashers and nuts. The

digger is ready to use.

INSTRUCTIONS (continued)

Operate the post hole digger only on a tractor with

540 RPM PTO shaft. The tractor’s engine speed

should not exceed 1200 RPM while digging.

CAUTION!

• Thoroughly read and understand your Operator’s

Manuals.

• Before beginning operation, clear area of objects that

wrap around the auger or might be thrown. Contact

local utility company to make certain there are no

buried gas lines, electrical cables, etc., in the work

area. Check for ditches, stumps, holes, or other

obstacles that could cause the tractor to roll.

• To dig properly, your digger must be able to raise or

lower through the highest and lowest points of your lift

arm travel without binding against the tractor frame.

Check carefully BEFORE attaching the auger. If it

does bind, adjust the tractor 3-pt. linkage so that all

movement is free.

If you have ANY questions, regarding the proper

operation of this digger, contact your dealer or the

manufacturer.

PREPARATION PROCEDURE

This Post Hole Digger was designed for one-man

operation from the tractor seat. It is the responsibility

of the operator to see that no one else is within

twenty-five feet (25’) of the digger when it is

operating.

• Set tractor brakes. Take tractor out of gear. Shift to

“Park” (if applicable).

• Do not allow anyone to stand behind, or to the side of

a rotating auger.

• Lower auger point slowly to the ground with the PTO

disengaged.

• With the auger point lowered to the ground, set the

engine speed to idle, then engage the PTO. Make

sure the auger point is on the ground before engag-

ing the PTO.

• Increase the speed as required so dirt is conveyed

from the hole. Refer to Owner’s Manual for sugges-

tions on PTO speed.

• Under no circumstances should the PTO be run in

excess of 540 RPM.

OPERATION

Figure 3