SB4 Strawblower - The Grun Company

SB4 Strawblower
Product & Operations Manual
Rev. 0701-00, April, 2007
Warning: Fire Hazard!
Exhaust from this device can ignite straw and hay. Do not store flammable or
combustible materials near the engine or within 10 feet of the exhaust.
The Grun Company designs and manufactures professional-level strawblowers,
hydromulchers and other environmental and landscaping equipment. These devices
contain moving parts, sharp cutting edges and hot surfaces. Do not use this equipment
unless you have read and understand all safety precautions and procedures contained
in this manual.
Grun Company Team Members - Bob and Frankie
Be Safety Aware!
These and additional hazard and warning decals are placed on your strawblower
in specific positions to ensure proper operation and user safety. Replace damaged
or unreadable decals immediately. Please read all safety and operations material
before using this device.
Model SB4 Strawblower Product & Operations Manual
Copyright © 2007, The Grun Company
Factory: (209) 577-1573 • Fax: (209) 577-1430
www.GrunCompany.com
Rev. 0701-00, April, 2007
Page 2
The Grun Company - A Higher Standard
Thank You!
Thank you for purchasing a Grun Strawblower. We are
confident that your new Grun Strawblower will provide you
with many years of reliable and consistent service.
Contents
Safety Decal Warning ......................................... 2
Thank You ............................................................ 3
The Grun brand was created by an established
manufacturer of agricultural and commercial landscaping
equipment to design, engineer and market strawblowers,
hydromulchers and other environmental equipment.
Under our brands, we have a 40-year history of precision
manufacturing highly engineered equipment for the
agricultural and landscape contractor industries.
Introduction ......................................................... 4
Grun products help contractors get into jobsite compliance
with the strict new EPA Phase ll requirements. Grun
products are best differentiated from competition through
the following traits:
Strawblowing Fundamentals ............................. 9
 PERFORMANCE –
Grun equipment sets the highest performance
specification in the industry. Period.
 DURABILITY –
Grun products use greater strength steel. Because
greater strength steel is more durable it extends the
life of your equipment.
 QUALITY –
Grun products are all laser cut and welded utilizing
our proprietary “slot & groove” assembly system,
which results in unmatched structural stability.
If you have any questions regarding operation, maintenance
or safety training on your Grun product please contact your
Grun dealer. Your Grun dealer will be more than happy to
help you.
Remember, Grun equipment sets the highest performance
specification in the industry. Period.
Strawblower Model Specifications ................... 4
Descriptions ........................................................ 5
Safety Information .............................................. 6
Unpacking ........................................................... 9
Getting Started .................................................... 10
Operating Instructions ....................................... 10
a. Standard Procedures ................................ 10
b. Starting ....................................................... 11
c. Shutdown ................................................... 12
Operating Tips .................................................... 12
a. Operating on a Slope ................................. 12
b. Bale Twine ................................................... 12
c. Adjusting the Length of Mulched Straw ... 12
Optional Leaf & Debris Vacuum ........................ 13
Service Notes ...................................................... 14
a. Overview & Service Notices ..................... 14
b. Oil Sentry™ ................................................ 14
c. Belt Removal & Replacement ................... 14
Maintenance Schedule ....................................... 15
Trouble Shooting ................................................ 16
Best regards,
Frequently Asked Questions ............................. 17
The Grun Company
Model SB4 Strawblower Parts List ................... 17
Assembly Diagrams ........................................... 18
a. SB4 Strawblower ....................................... 18
b. Feeder Tray Assembly .............................. 19
c. Nozzle Assembly ....................................... 20
d. Leaf & Debris Vacuum Assembly ............. 21
e. Flail Chamber Housing ............................. 22
f. Belt Housing .............................................. 23
g. Fan Housing ............................................... 24
h. Fan Weldment ............................................ 25
Warranty .............................................................. 26
a. Engine Emissions Maintenance Notice ... 26
b. Limited Product Warranty ......................... 26
Strawblower SB4 Product & Operations Manual
Page 3
Introduction
Your Grun Strawblower will give you years of
reliable and consistent service if you always follow
the manufacturer instructions for proper operation,
safety and maintenance.
All operators and crew members working with or
near your Grun Strawblower must read this manual
in its entirety to ensure proper operation, safety and
maintenance.
This Grun Strawblower product manual covers the
following models of Grun Strawblowers:

Grun Model SB4 Strawblower – both skid
type and trailer mounted. The Model SB4 has
a four (4) ton per hour processing capacity.
It is powered by a gasoline engine. Only use
unleaded regular gasoline in the Model SB4
Strawblower.
The Grun Company reserves the right to make
changes in design and specifications without
notice.
Grun Company Strawblowers set the highest performance
specifications in the industry.
Grun Model SB4 Strawblower Specifications
Engine ................................... Kohler 20 hp. Electric start
(standard).
Engine safety system .......... Low oil pressure shut off.
Capacity ............................... 3 bales per minute (4 tons per hour).
Fuel tank ............................... 9 gallon (34 liter) high impact poly
resin tank.
Blower fan ............................ 17” (43 mm) diameter dynamically
balanced fan blade.
Discharge distance ............. Up to 55’ (16.8 m).
Feeder tray ........................... Manual.
Discharge head .................... 360 degrees horizontal rotation on
roller bearings. 60 degrees vertical
travel.
Feed tray .............................. Horizontal, collapsible feeder tray.
Weight ................................... 800 lbs (362 kg), skid model.
Overall length ...................... 60” (1,524 mm).
Height ................................... 63.5” (1,613 mm).
Width ..................................... 27” (686 mm).
Battery .................................. 12v.
Flail chains ........................... Two 5/16” hardened welded
removable leaf chains standard (link
chains optional).
Flail chamber ....................... 7 cubic feet (0.20 cubic meters).
Engine meter ........................ Hour meter standard.
The Grun Model SB4 Strawblower is
aerodynamically engineered and features
a nine gallon fuel tank and heavy gauge
steel throughout. The drive system
generates a discharge velocity exceeding
hurricane force winds.
Leaf & debris vacuum ......... Available as an optional attachment.
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The Grun Company - A Higher Standard
Descriptions
Standard Skid Configuration
Battery ................................The 12-volt battery is located underneath the flail chamber opposite the fuel tank.
Engine.................................A Kohler gas engine powers the SB4.
Fan Housing .......................The fan housing protects the operator and work
crew from the impeller fan.
Feeder Shield .....................The feeder shield protects the operator.
Feeder Tray ........................Straw bales are loaded onto feeder tray to be fed
into the strawblower. Operators should safely
remove all bale twine before feeding straw into
the machine.
Flail Chamber .....................The flail chamber houses the shaft and flail
chains that tear apart the bale. Keep hands,
feet, bale twine and foreign objects out of flail
chamber while engine is running.
Fuel Tank ............................The SB4 fuel tank is located underneath the flail
chamber.
Lift Point .............................The SB4 lift point is located above the fan
housing near the flail chamber. See illustration.
Nozzle .................................The nozzle allows for vertical maneuverability
Make certain you use lift
and precise distribution of straw.
straps capable of supporting
the entire weight of the
Platform ..............................The optional trailer has a platform with guard
device.
rails on both sides of the machine for operator
comfort and safety.
Turret ..................................Rotates 360 degrees on roller bearings and allows for horizontal maneuverability
of nozzle.
Optional Towable Unit Configuration
Ball Hitch ............................The optional towable unit comes standard with a ball hitch unless pintle or other
option is specified.
Jack Stand .........................The optional towable unit comes standard with a jack stand. The jack stand may be
used when the unit is not in operation.
Safety Chains .....................The optional towable unit comes standard with safety chains that must be used
when the unit is attached to a tow vehicle.
Trailer ..................................Allows for easy transport of strawblower.
Transport Locking Arm
Feeder Tray
Flail Chamber
Feeder Shield
Lift
Point
Turret
Nozzle
Fan Housing
Belt Housing
Grun Model SB4
Strawblower
Engine
(Skid Configuration shown)
Fuel Tank
Strawblower SB4 Product & Operations Manual
Page 5
Safety Information
Failure to understand and obey safety information and warnings may result in injury or
death to you and/or others!
Whenever this safety symbol is used please make sure you fully understand the
information presented. If you do not fully understand any part of this manual please
immediately contact your dealer or The Grun Company for clarification.
The telephone number for contacting The Grun Company factory is (209) 577-1430. The Grun Company
is open Monday through Friday from 8:00AM to 5:00PM Pacific Time. Contact information for The Grun
Company also appears online at www.GrunCompany.com.
Safety Warning!
• To prevent eye injury, always wear safety glasses while operating or servicing the equipment.
• Only use genuine factory parts. Failure to do so may result in product malfunction and possible injury to
the operator and/or others. Failure to use genuine factory parts will void the product warranty.
• If you can tighten nuts and screws without feeling resistance before they are completely tightened then
replace them. Only replace nuts and screws with factory authorized replacement parts.
• If hardware is not secure or if hardware is over-tightened then equipment failure may result which could
result in a safety hazard.
• Do not operate Strawblower indoors.
• Wear ear protection when operating strawblower to prevent long-term hearing damage.
• Immediately remove any build-up of straw around the engine and exhaust areas.
• Do not smoke within 30 feet of the strawblower or anywhere on the jobsite while the strawblower is in
operation.
Fuel Safety Warning! Fuel is extremely flammable and highly explosive.
• Allow engine to cool before refueling.
• Do not smoke or allow open flames or sparks within 30’ of the machine while refueling or performing
maintenance.
• Never remove the fuel tank cap or add fuel when the engine is running or when the engine is hot.
• Never fill the fuel tank indoors.
• Wipe up spilled fuel immediately and completely.
• Do not store fuel in a room with an appliance that has a pilot light or where electrical appliances or
switches may cause sparks.
• Always store fuel outdoors in a safety can (a can which has a flame arrestor and pressure relief valve in
pour spout).
• Gasoline fumes are heavy and will sink to the lowest point, collecting and becoming more and more
hazardous. 1 part gasoline in 20 parts air will explode easily and violently.
• Never store the equipment with gasoline in the tank inside a building where fumes may reach an open
flame or spark. Allow the engine to cool before storing in any enclosure.
• Do not run indoors – exhaust fumes are dangerous.
Guards, Shields & Safety Devices
• Keep all guards, shields and safety devices in place at all times. Only remove guards, shields and safety
devices when absolutely necessary for service or maintenance.
• Replace all guards, shields and safety devices immediately following service or maintenance.
• Replace guards, shields and safety devices to the original manufacturer specifications and settings.
• Always check all guards, shields and safety devices prior to operating equipment.
• Replace all worn, damaged, unusable, missing or lost guards, shields and safety devices before operating
equipment.
• Failure to follow these guidelines may result in injury or death to the operator or bystanders.
Safety Decals
• If safety related or instructional decals become illegible or are removed, replace them immediately.
• If parts that have safety related or instructional decals attached are replaced, make sure the current
versions of the decals are on the replacement parts before operating equipment.
• Replace damaged or missing safety related or instructional decals. New decals may be obtained from The
Grun Company or your Grun dealer.
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The Grun Company - A Higher Standard
Safety Information, continued
Equipment & Controls
• Read and understand the owner’s manual before operating equipment. Always instruct all users and crew members on
safe equipment operation and usage procedures prior to operating equipment.
• Altering Grun equipment in any manner will void the warranty and may result in injury or death to the operator or
bystanders.
• Know the location and function of all controls and how to stop the equipment in an emergency prior to operating
equipment.
• Prior to operating the equipment inspect all nuts, bolts, screws and all other fasteners for tightness to verify that they are
secured and to help ensure safe operation of this equipment.
• Prior to operating equipment always check all guards, shields and safety devices.
Towing (If Applicable)
The owner/operator is responsible for licensing
the towable unit and ensuring that it meets all
requirements in the state where it is used.
• Use the safety chains when towing.
• Use the correct size ball hitch on the tow vehicle.
• The jack stand should be up and locked in the
transport position.
• Keep the tire pressure inflated to the manufacturer’s
specification and make sure both tires are inflated
to equal pressure.
• Prior to towing the equipment always check the
trailer wheel lug nuts to make sure they are tight.
• Lock and pin the pivot head in place whenever the
unit is being transported.
• Make sure drive and signal lights are operational.
Exhaust fumes from the SB4’s engine can
ignite straw and hay! Store all flamable items
at least 10 feet away from the engine.
Before Operation
•
•
•
•
•
Before operating this equipment, read and understand the owner’s manual.
Do not allow minor children to operate this machine.
Wear approved eye and ear protection and other safety equipment while operating the machine.
Make sure bolts holding the tongue are secure and the jack is in the transport position. Use the safety chains.
Engine governor settings are preset and should not be changed; any change can damage moving parts and void the
warranty.
• Prior to operating the equipment inspect all nuts, bolts, screws and all other fasteners for tightness to verify that they are
secured and to help ensure safe operation of this equipment.
• Replace damaged or missing related or instructional decals. If parts that have safety related or instructional decals
attached are replaced, make sure the current versions of the decals are on the replacement parts before operating
equipment.
Always use the safety chains
when towing. Towable models
only.
Read and understand all safety warning
decals. Replace damaged decals
immediately.
Strawblower SB4 Product & Operations Manual
Ear and eye protection must
be worn when operating the
strawblower.
Page 7
Safety Information, continued
During Operation
Always keep a fire extinguisher near the strawblower during operation.
• Never force material into the machine. When feeding material, make certain there are no foreign objects
such as rocks, cans, bottles or other hard materials included.
• If the strawblower should become clogged, shut off the engine and allow it to come to a complete stop
before attempting to clean material. If a foreign object should strike the flail chains or fan mechanism
of the machine and cause an unusual noise or vibration, shut the engine off immediately and allow it to
come to a complete stop. Disconnect the spark plug wires from the spark plugs on the engine, and then
do the following:
- Inspect for damage.
- Repair or replace any damaged parts.
- Check for and tighten any loose bolts, nuts, fasteners or parts.
• Keep clothing and all body parts away from rotating parts.
• Keep the engine area free of oil, debris and other accumulations.
• Keep all safety shields, insulation plates and guards in place and in
good working condition.
• Keep the engine and muffler areas free of straw. Failure to do so
could result in fire.
• Periodically clean area around engine to lessen the possibility of fire.
• Do not smoke within 30 feet of the strawblower or anywhere on the
jobsite while the strawblower is in operation.
• Engine governor should not be changed. Any changes made to
the engine governor can damage moving parts and will void the
warranty.
• Do not allow bale twine to get into the flail chamber. Have your crew
pull the twine clear of the machine when they are prepping straw
bales for insertion into the flail chamber. If bale twine gets into the
flail chamber it will likely wrap around the flail chain shaft. Clean
all bale twine off the flail chain shaft after every use. Be certain you
disconnect the spark plug wire from the spark plug on the engine
before reaching into the flail chamber or fan housing.
LOOSE BALE TWINE CAN SEVER LIMBS!
Battery Safety Warning!
Observe all safety warnings printed on the battery.
•
•
•
•
•
Ventilate when charging battery or changing battery.
Do not charge battery indoors or in an enclosed space.
Do not produce sparks from cable clamps, tools, or other sources; and
Do not allow sparks, flames or smoking within 30’ of the battery.
Always wear safety glasses when working near the battery.
Do not allow bale twine to get pulled into
the chains in the flail chamber. This can
result in serious injury or even death.
Page 8
The SB4 battery is located
opposite the gas tank under
the flail chamber.
Disengage the transport
locking arm by removing the
pin prior to operation.
The Grun Company - A Higher Standard
Strawblowing Fundamentals
Strawblowers, straw blowers, hay blowers, straw mulchers or
simply mulchers are all the same equipment. All strawblowers
make it possible to achieve a 30-40% material savings and to
achieve up to an 80% labor savings vs. hand mulching straw.
Strawblowers cost-effectively mulch baled straw and disperse it
on the ground as an evenly distributed blanket. The results save
contractors both time and money by reducing & using labor and
materials more efficiently. Strawblowers are a cost effective tool
for job site erosion control compliance as mandated by federal
EPA requirements. Mulched straw also provides insulation to
newly planted seed.
Grun Strawblowers are designed to accommodate three types of
material: straw, hay, and rice straw.
Grun Strawblowers process rectangular bales of straw in either
two-twine / 50 lbs or three-twine / 75 lbs bale configurations.
Have your crew pull the twine clear of the machine when they
are prepping straw bales for insertion into the flail chamber. If
bale twine gets into the flail chamber it will likely wrap around
the flail chain shaft. Clean all bale twine off the flail chain shaft
after every use.
Straw is baled in slabs or flakes. A straw bale has approximately
8 – 12 flakes per bale. After removing the bale twine quickly
hand feed the flakes of straw into the flail chamber. Your
strawblower will mulch the straw and disperse it in a uniform
length of between 4” to 10”.
Processed straw mulch is generally applied at a rate of 1 ½
tons per acre. Over-mulching will diminish the benefits of
strawblowing by actually reducing the air contact needed with
the soil.
Grun Company Team Member Matt works with an SB7 Strawblower.
The Grun Model SB4 Strawblower will process four (4) tons of dry straw per hour. The Grun Model SB7 Strawblower will
process seven (7) tons of dry straw per hour. Production limitations on the jobsite center around getting enough straw to
the unit fast enough and on how fast the operator can feed the machine. The machine itself will not pose a production
limitation. The ability of the machine to process material exceeds the ability of most work crew members responsible for
feeding the machine.
Unpacking
Your new Grun Strawblower is shipped fully assembled except
for the feeder tray. Assembly diagrams for the tray appear
on page 19. For transportation safety, your strawblower is
shipped with the battery and the spark plugs disconnected,
without engine fuel and with only the absolute minimal level
of engine oil required to perform a quality control start up at
the factory. Check the engine manual and fill the engine oil to
the level specified in the engine manual using the type of oil
recommended by the engine manufacturer.
Prior to operation double check and verify that all packing
materials and tie down straps have been removed from the
machine. Also inspect the turret’s bearing bolts that allow
rotation of the nozzle. Visually inspect the interior of the flail
chamber, impeller fan and discharge nozzle to verify that there
is no debris inside the machine. Visually inspect the engine
area and muffler to verify that no packing materials or debris
are near the engine or inside or near the muffler.
Strawblower SB4 Product & Operations Manual
Grun Company Team Member Danilo demonstrates how to attach
the Model SB4’s feeder tray. Refer to the diagram on page 19 for
feeder tray assembly details.
Page 9
Getting Started
Prior to initial operation you must first complete the following steps:
1. Read this entire product manual and familiarize yourself with the safe operation and maintenance of your machine.
2. For safety, the engine is shipped without fuel and with only
the absolute minimal level of engine oil required to perform a
quality control start up at the factory. Therefore you must check
the engine manual and fill the engine oil to the level specified
in the engine manual using the type of oil specified by the
engine manufacturer for your geographic area. Be aware that oil
specifications may change over the course of a year due to local
temperature variations. Do not add oil to the gasoline.
3. Connect the spark plug wires. Connect the battery cables.
4. Fill the fuel tank with the appropriate type of fuel. The Grun
Model SB4 Strawblower uses regular unleaded gasoline.
5. Check and tighten all of the wheel lug nuts on trailer models.
6. Visually inspect the interior of the flail chamber, impeller fan
and discharge nozzle to verify that there is no debris inside the
machine.
Refer to the engine owner’s manual supplied
with your strawblower for oil specifics.
7. Visually inspect the engine area and muffler to verify that no packing materials or debris are near the engine or inside or
near the muffler.
8. Completely fill out and mail your warranty card. Your machine only has a valid warranty if a completed warranty card is
on file with The Grun Company.
Operating Instructions
Standard Procedures
1. Wear eye and ear protection at all times during operation.
2. Check to make sure you know what type of fuel the engine uses. The Grun Model SB4 Strawblower uses unleaded
regular gasoline - NOT diesel. Fill the tank with the appropriate fuel. Do not add oil to the gasoline. Make sure vent on
fuel tank is open.
3. If appropriate, hitch the towable unit to the tow vehicle.
4. Check the flail chamber and fan housing to ensure that they are free of
debris and foreign objects.
5. Always check the oil level before each use.
6. Do NOT store flammable or combustible material near the engine or
exhaust stream. The engine and the exhaust can cause fires!
6. Before starting engine, make sure that the engine throttle is down (turtle)
against the right stop. (See illustration on page 11)
7. If engine is cold, pull out the choke. When restarting a warm engine, it is
not necessary to use the choke.
Oil level can be checked with the
dipstick located on the rear of the
engine.
8. Turn the key switch to the start position and release as soon as the engine
starts. Do not turn the starter over for more than 10 seconds.
9. Once engine is running, gradually open the choke and allow the engine to warm up.
10. Raise engine throttle to maximum (rabbit) before feeding straw into the flail chamber.
11. Place a bale onto the feeder tray.
12. Remove all twine or wire used to bind the bale. Twine or wire can wrap around shaft and damage operator or unit.
13. Move the spout up, down or side-to-side to dispense material where desired.
Always check overhead clearance when rotating nozzle or transporting strawblower.
Never point nozzle in the direction of bystanders. Keep bystanders out of area of
operation to prevent them from being hit by flying objects.
Page 10
The Grun Company - A Higher Standard
Operating Instructions, continued
Starting
1. Place the throttle control midway between the “slow” and “fast” positions. Place the choke control into the “on”
position. See the illustration on this page for correct settings.
2. Start the engine by activating the key switch. Release the switch as soon as the engine starts.
NOTE: Do not crank the engine continuously for more than
10 seconds at a time. If the engine does not start, allow a 60
second cool down period between starting attempts. Failure
to follow these guidelines can burn out, or permanently
damage, the starter motor.
NOTE: Upon start-up, a metallic ticking may occur. This is
caused by hydraulic lifter leakdown during storage. Run the
engine for 5 minutes. The noise will normally cease in the
first minute. If noise continues, run the engine at midthrottle
for 20 minutes. If noise persists, take the engine to your local
authorized Kohler Engine Service Dealer.
This is the proper throttle and choke position for
starting your strawblower.
NOTE: If the engine develops sufficient speed to disengage
the starter but does not keep running (a false start), engine
rotation must be allowed to come to a complete stop before attempting to restart the engine. If the starter is engaged
while the flywheel is rotating, the starter pinion and flywheel ring gear may clash resulting in damage to the starter.
If the starter does not turn the engine over, shut off starter
immediately. Do not make further attempts to start the
engine until the condition is corrected. Do not jump start
using another battery. See your Kohler Engine Service Dealer
for service assistance.
3. For a Cold Engine – Gradually return the choke control to
the “off ” position after the engine starts and warms up. The
engine/equipment may be operated during the warm-up
period, but it may be necessary to leave the choke partially on
until the engine warms up.
4. For a Warm Engine – Return choke to “off ” position as soon
as engine starts.
Cold Weather Starting Hints
1. Be sure to use the proper oil for the
temperature expected. See oil reference table
on page 10 or refer to the engine manual.
2. Be sure the battery is in good condition. A
warm battery has much more starting capacity
than a cold battery.
3. Use fresh winter grade fuel. NOTE: Winter
grade gasoline has higher volatility to improve
starting. Do not use gasoline left over from
summer.
WARNING: Hot Parts!
Engine components can get extremely hot from operation. To prevent severe burns,
do not touch these areas while the engine is running, or immediately after it is turned
off. Never operate the engine with heat shields or guards removed. Do not allow straw
or other flammable or combustible materials to come in contact with the engine or the
exhaust. Failure to do so may result in fire!
WARNING: Accidental Starts!
Accidental starting can cause severe injury or death. Before working on the engine or
equipment, disable the engine as follows: 1) Disconnect the spark plug lead(s).
2) Disconnect negative (-) battery cable from battery.
WARNING: Angle of Operation!
Your strawblower engine will operate continuously at angles up to 25°. Check oil level
to assure crankcase oil level is at the “F” mark on the dipstick. Do not operate the
engine continuously at angles exceeding 25° in any direction. Engine damage could
result from insufficient lubrication.
Strawblower SB4 Product & Operations Manual
Page 11
Operating Instructions, continued
Shutdown
1. Remove straw bales from feeder tray and away from flail chains.
2. Allow the strawblower to run empty for a brief period so that it cleans itself
of material.
3. Lower the engine throttle to minimum speed (turtle).
4. Allow engine to run briefly at this speed before turning it off using the key.
5. Secure the nozzle to the transport locking arm prior to moving the
strawblower.
6. Do not store the strawblower within 10 feet of combustible or flammable
material.
Operating Tips
Operating On a Slope
•
•
•
•
Never exceed a 25 degree angle while strawblower is in operation.
Run up and down steep slopes, never across the face.
Reduce speed on slopes and in sharp turns to prevent tipping or loss of control.
Use extreme caution when changing directions on slopes.
Bale Twine
•
•
•
Have your crew pull the twine clear of the machine when they are prepping straw bales for insertion into the flail
chamber.
If bale twine gets into the flail chamber it will likely wrap around the flail chain shaft. Clean all bale twine off the flail
chain shaft after every use.
Be certain you disconnect the spark plug wires from the spark plugs on the engine before reaching into the flail
chamber or fan housing.
Adjusting the Length of Mulched Straw
To adjust the length of the cut straw that is discharged from
your strawblower you will need to perform the following steps:
1. Safely disable the engine by removing the spark plug wires
from the engine’s spark plugs.
2. Disconnect the negative ground cable from the battery.
3. Open the top of the flail chamber. (Part B on page 22)
4. Loosen the respective flail chain collars as follows;
For longer mulched straw, you may safely remove the chain
pair furthest away from the fan (A).
For shorter mulched straw, move the chain pairs (A and
B) slightly closer to the fan. If you move them too far, the
chains may actually block the straw causing the machine to
clog. Use slight adjustments to reach your desired effect.
5. Readjust and retighten the flail chain collars using blue
(medium) Locktite™ or a reliable equivalent.
Warning: Unattended Operation!
Do not leave machine unattended, or attempt service or inspection unless the
machine has come to a complete stop, the engine has been shut off, and the spark
plugs have been disconnected.
Please contact The Grun Company or any affiliated Grun dealership for assistance if any part of this manual requires
further explanation. Your safety and the performance of the strawblower depends on a clear understanding of the
material contained in this manual.
For technical assistance or additional information, please contact:
The Grun Company
Factory (209) 577-1430 • Fax (209) 577-1430 • www.GrunCompany.com
Page 12
The Grun Company - A Higher Standard
Optional Leaf & Debris Vacuum
The Grun Model SB4 Strawblower optional Leaf and Debris Vacuum attachment is a leaf and debris vacuum combined
with a debris loader. This attachment will extend the usage season of your strawblower to nearly year-round while
eliminating the need to buy or rent expensive dedicated leaf vacuums and debris loaders. This attachment vacuums light
material yard waste through the SB4 Strawblower’s impeller where it is mulched and discharged out the other end into your
trailer or debris container.
Required Parts
The Grun Model SB4 Strawblower Leaf and Debris Vacuum
requires the following optional attachment parts:
1. 50’ x 6” flexible hose
2. Clamp & handle for 50’ discharge hose mounting
3. Bracket & handle for vacuum conversion
Assembly Instructions
NEVER disassemble or assemble any attachment or perform
any service work unless your strawblower is turned off, has
come to a complete stop and the spark plug wires have been
disconnected! Failure to do so could lead to serious injury or
even death. Please refer to the proper shutdown and service
procedures described on page 14.
A full assembly and parts diagram for the Grun Model SB4
Leaf and Debris Vacuum can be found on page 21.
1. Disassemble the strawblower tray and store all parts together in a safe place where they will not be separated or lost. If
desired, the feeder tray may be left on the machine while using the Grun Leaf and Debris Vacuum.
2. Attach the conversion plates as shown in the following illustrations and described on page 21.
3. Attached the hose clamp.
4. Attach the hose.
5. Secure the strawblower’s discharge nozzle in a safe direction prior to using the vacuum.
Do not attempt to vacuum bark mulch, rocks or any kind of soil. The leaf and
debris vacuum option is designed for yard waste only. It is not designed to vacuum
aggregates, soils or any other heavy materials. Vacuuming these materials will void
your warranty.
Grun Company Team Member Danilo demonstrates the steps necessary to attach the Grun Leaf and Debris
Vacuum to the Model SB4 Strawblower. Please also refer to the illustrated diagram on page 21 for vacuum
assembly details.
Strawblower SB4 Product & Operations Manual
Page 13
Service Notes
Safety warning! Before inspecting flail chains, feeder shield or impeller fan housing,
make sure blower has come to a complete stop, engine is turned off, and spark plug
wires and negative battery cable are disconnected.
Before servicing or inspecting the strawblower make sure the engine is shut off and all moving parts
have stopped.
 Disconnect the spark plug wires from the spark plugs and disconnect the negative battery cable to
prevent the engine from being turned on during service.
 Always wear safety glasses when servicing the strawblower.
 Replace the feeder shield immediately if it becomes damaged or worn.
Note: refer to engine manual for more detailed information on engine maintenance and operation. See any authorized
Kohler dealer for service to engine.

Overview & Service Notices
Check Oil Level
The importance of checking and maintaining the proper oil level in the crankcase
cannot be overemphasized. Check oil BEFORE EACH USE as follows:
1. Make sure the engine is stopped, level, and is cool so the oil has had time to drain
into the sump.
2. To keep dirt, debris, etc., out of the engine, clean the area around the dipstick
before removing it.
3. Remove the dipstick; wipe oil off. Reinsert the dipstick into the tube and press all
the way down.
4. Remove the dipstick and check the oil level. The oil level should be up to, but not over, the “F” mark on the dipstick.
5. If the level is low, add oil of the proper type, up to the “F” mark on the dipstick. Always check the level with the
dipstick before adding more oil.
NOTE: To prevent extensive engine wear or damage, always maintain the proper oil
level in the crankcase. Never operate the engine with the oil level below the “L” mark
or over the “F” mark on the dipstick.
Oil Sentry™
Your Grun Model SB4 Strawblower is equipped with an Oil Sentry™ oil pressure switch. If the oil pressure decreases below
an acceptable level, the Oil Sentry™ will shut off the engine.
NOTE: Make sure the oil level is checked BEFORE EACH USE and is maintained up to the “F” mark on the dipstick.
This includes engines equipped with Oil Sentry™.
Belt Removal & Replacement
Belt wear and slippage may cause low power situations and decrease
the discharge distance of your strawblower.
Before inspecting or replacing the belts, shut down the machine and
prepare it for service by following the safety notes at the top of this
page. Then proceed as follows;
1. Using the assembly diagrams on pages 23 and 24, remove the 4
screws holding the stainless steel heat shield (Page 23, part D).
2. Remove the 4 bolts holding the guard housing (Page 23, part B).
3. Confirm that the auto tensioner is snug against the belts (Page
24, part D).
4. Inspect the belts for slippage or wear.
5. To replace the belts, loosen the bolt holding the auto tensioner
(Page 24, part C).
6. Remove and replace belts with a matching set as necessary.
7. Reassemble in reverse order making sure that the auto tensioner
is snug against the belts.
Page 14
Be aware that oil specifications may change
over the course of a year due to local
temperature variations. Never add oil to the
gasoline used in your strawblower.
The Grun Company - A Higher Standard
Maintenance Schedule
These required maintenance procedures for the Grun Model SB4 Strawblower should be performed at the frequency stated
in the table. They should also be included as part of any seasonal tune-up.
Service Schedule
Daily
Before Starting Engine
Service Action
Check engine oil level
• See dipstick level and fill to specified level
Fill fuel tank
• Use the appropriate fuel for your engine – The Model SB4 uses regular
unleaded gasoline.
Check air cleaner and precleaner element for dirty, loose or damaged parts
• Clean as necessary
• This action may be necessary more frequently when used in
excessively dusty conditions
Visually inspect flail chains, feeder shield and turret bearings for wear and fit
• Tighten or replace as necessary
• Clean all bale twine off the flail chains after every use
After Every 40 Hours
of Service
Visually inspect belts, bolts, fittings and hoses
• Tighten as needed
Grease all zerks
• Do not over-lubricate. Over-greasing may cause damage to bearing
seals.
Check tire pressure if applicable
• Refer to sidewall of tire for appropriate ratings
After First 50 Hours
of Service
Change engine oil and filter (every 100 hours thereafter)
• Refer to engine manual
100 Hour Service
Change engine oil and filter
• Refer to engine manual
Check valve clearance (every 250 hours thereafter)
• Refer to engine manual
Replace air cleaner element
• Refer to engine manual
250 Hour Service
Check valve clearance
• Refer to engine manual
400 Hour Service
Replace air cleaner cartridge
• Refer to engine manual
Change fuel filter
• Refer to engine manual
Annually or After Every Service bendix starter drive
• Refer to engine manual
500 Hours Service
Disassemble and clean solenoid shift starter if applicable
• Refer to engine manual
500 Hour Service
Have crankshaft spline lubricated
• Refer to engine manual
600 Hour Service
Replace safety filter cartridge
• Refer to engine manual
Annual Service
Change spark plugs
• Refer to engine manual
Change oil
• Refer to engine manual
Strawblower SB4 Product & Operations Manual
Page 15
Trouble Shooting
Problem
Engine will not
start
What to Check
•
Improper control settings
•
Fuel level may be low
•
Engine may be too low or too full of oil
•
Battery charge may be too low
•
Possible internal problems
•
Fuel level may be low
•
Engine may be too low or too full of oil
•
Fuel filter may be clogged
•
Fuel tank vent may be closed
•
Air breather may be clogged
Unit vibrates
•
Material may be wrapped around flail shaft.
•
Blower may be damaged.
Engine
•
Please refer to the engine manual shipped with your strawblower for enginespecific problems.
Turret / nozzle will
not rotate
•
Check turret head bearings for dirt
•
Inspect for missing or loose turret bearings
Flail Chamber
makes unusual
noise when in use
•
Make sure flail chains are tightly secured after adjustment. See page 12.
Mulched straw is
too long or too
short
•
Adjust the flail chains as described on page 12.
•
Wet straw will not mulch as well as dry straw.
Clogged Fan
Housing
•
Immediately shut down the machine and prepare it for service by following the
service safety notes on the top of page 14.
Using the diagram on page 18, remove the nozzle (15) and transition (3).
Remove the clogged material from the fan housing (2) and reassemble.
Clogged Flail
Chamber
•
Immediately shut down the machine and prepare it for service by following the
service safety notes on the top of page 14.
Using the diagram on page 20, remove the flail chamber cover (part B).
Remove the clogged material from the flail chamber and reassemble.
Low power or
short discharge
distance
•
Immediately shut down the machine and prepare it for service by following the
service safety notes on the top of page 14.
Using the instructions on page 14, inspect the belts for slippage or wear.
Remove and replace if necessary.
Confirm that the belt tensioner is snug against the belts.
Engine shuts off
during operation
Page 16
The Grun Company - A Higher Standard
Frequently Asked Questions
Q: Can I use rice straw?
A: Yes, however rice straw is a very fibrous material. Leaf style flail chains are recommended for processing rice straw. If
you do not already have factory approved leaf style flail chains you can order them from The Grun Company.
Q: Can I use hay?
A: Yes, however hay is a more fibrous material than straw. Leaf style flail chains are recommended for processing hay. If
you do not already have factory approved motorcycle style flail chains you can order them from The Grun Company.
Q: Can I use pine straw?
A: No. Pine straw is not recommended for use in strawblowers.
Q: Can I use bark mulch?
A: No! This will damage your strawblower and void your warranty.
Q: Are the flail chains covered under my warranty?
A: No, the flail chains are wear items and are not covered under warranty.
Q: Can I use my Strawblower as a leaf & debris vacuum?
A: Yes, however you will need to order a conversion kit and a hose from The
Grun Company in order to convert your strawblower into a leaf & debris
vacuum (see page 13).
Q: Can I use wet straw?
A: Yes, however wet straw increases the likelihood of clogging your
strawblower. The wetter the material, the greater the chance of clogging.
Q: Can I use wet and dry straw in the same work session?
A: Sometimes. You can switch from dry to wet straw in the same work
session, but switching from wet to dry straw increases the chance of
clogging the machine.
Grun Company Team Members Rodney and Danilo
work on a Model SB4 Strawblower
Q: Can I run bale twine through the machine?
A: No. Have your crew pull the twine clear of the machine when they are
prepping straw bales for insertion into the flail chamber. If bale twine gets into the flail chamber it will likely wrap
around the flail chain shaft. Clean all bale twine off the flail chain shaft after every use.
Grun Model SB4 Strawblower Parts List
SB4-1010
Frame Weldment
SB4-1020-D
SB4-1020-G
SB4-1020-H
SB4-1020-M
SB4-1020-N
SB4-1020-O
SB4-1020-Q
Cover
Feeder Shield
All Thread
Bearing Box Cover
Logo Plate
Logo Backing
Lifting Plate
SB4-1030
SB4-1030-E
SB4-1030-G
SB4-1030-H
Fan Housing
Tensioner Bracket
Tensioner
Tensioner Hub
SB4-1040
Transition
SB4-1050
SB4-1050
SB4-1050-I
SB4-1050-L
Elbow Weldment
Nozzle Weldment
Handle Weldment
Flexible Tubing
SB4-1080-A
Support Strap
SB4-1090
Transport Locking
Arm
SB4-1060
SB4-1060-A
SB4-1060-B
SB4-1060-D
SB4-1060-E
SB4-1060-F
Guard Housing
Guard Front
Guard with Cable
Channel
Guard Bracket
Heat Shield
Insulation
SB4-1100
SB4-1100-E
SB4-1110-K
SB4-1110-F
SB4-1120
SB4-1130
Fan Weldment
Taper Lock
Link flail Chains
Leaf flail Chains
Bearing Block
Fan Shaft
SB4-1070-A
SB4-1070-B
Feeder Tray
Feeder Tray Ext.
SB4-1140
Vacuum Cover
Weldment
Louver cover
Strawblower SB4 Product & Operations Manual
SB4-1140-C
Page 17
Page 18
The Grun Company - A Higher Standard
Strawblower SB4 Product & Operations Manual
Page 19
Page 20
The Grun Company - A Higher Standard
Strawblower SB4 Product & Operations Manual
Page 21
Page 22
The Grun Company - A Higher Standard
Strawblower SB4 Product & Operations Manual
Page 23
Page 24
The Grun Company - A Higher Standard
Strawblower SB4 Product & Operations Manual
Page 25
Warranty
Your Grun Strawblower is warranted against defects in workmanship and materials for a period of twelve months or 500
operating hours (whichever comes first) from the original date of sale to the original purchaser. The Grun Company will
repair or replace, at our option, any part that our examination shows to be defective. Warranty is limited to parts, labor and
ground freight delivery of replacement parts. The user will pay freight charges for parts submitted under this warranty.
No product or part may be returned for warranty consideration without prior approval from The Grun Company.
This warranty does not apply to parts subjected to misuse, abuse, alteration, improper or inadequate maintenance, or normal wear (including belts, couplers and flail chains).
Engines (gasoline and / or diesel) are not covered under this warranty. Refer to the engine manufacturer’s warranty for
specific engine warranty information.
The Grun Company, its agents or representatives, make or imply no other warranties.
Engine Emissions Maintenance Notice
Maintenance, repair, or replacement of the engine’s emission control devices and systems, which are being done at the
customer’s expense, may be performed by any non-road engine repair establishment or individual. Warranty repairs must
be performed by an authorized service outlet recognized by the engine manufacturer. Please refer to the engine owner’s
manual that was supplied with your strawblower for further details.
Page 26
The Grun Company - A Higher Standard
A HIGHER STANDARD
Grun Model SB7 Strawblower
Heavier steel and laser cut assembly.
Greater discharge distance.
Grun equipment sets the highest performance
specification in the industry. Period.
Factory (209) 577-1430 • Sales (314) 269-7986
Model SB4 Strawblower Product & Operations Manual
Factory: (209) 577-1573 • Fax: (209) 577-1430
www.GrunCompany.com
Copyright © 2007, The Grun Company
Rev. 0701-00, April, 2007
Grun, The Grun Company, and all associated logos, emblems, line drawings and designs are trademarks of The Grun Company, Incorporated.
Portions of this manual may contain material held under copyright by other equipment manufacturers.
All rights reserved, including the right of reproduction in whole or in part in any form.