drago GT User manual

CLINIC GUIDE

MODEL IDENTIFICATION
1 Corn Head Clinic Guide - GT
GT
The GT corn head was introduced in 2016. The design of this head introduced features such as the
QuadSuspension™ for the deck plates, individual slip clutches on individual components, and a 100% gear driven
driveline. Each row unit has independent slip clutches for each gathering chain, the stalk rollers, and the stalk
chopper (if equipped).

INTRODUCTION
Corn Head Clinic Guide - GT
2
Table of Contents
MAINTENANCE ............................................................................................................................................................3
REQUIRED FLUIDS ..................................................................................................................................................... 4
LUBRICANT PART NUMBERS ..................................................................................................................................... 4
MAINTENANCE SCHEDULE ........................................................................................................................................ 5
PRE-SEASON ........................................................................................................................................................... 5
NORMAL OPERATION ............................................................................................................................................. 5
DOWN CORN ........................................................................................................................................................... 6
PRE-SEASON ............................................................................................................................................................... 7
20-HOUR ..................................................................................................................................................................... 8
100-HOUR ................................................................................................................................................................... 8
250-HOUR OR YEARLY ............................................................................................................................................... 9
INITIAL SETTINGS................................................................................................................................................... 11
CORN HEAD ANGLE .................................................................................................................................................... 11
HEAD SPEED ............................................................................................................................................................. 12
SNOUT ADJUSTMENTS ............................................................................................................................................. 13
DECK PLATE GAP ...................................................................................................................................................... 13
DECK PLATE TENSION.............................................................................................................................................. 14
GATHERING CHAIN TENSION .................................................................................................................................. 14
PART REPLACEMENT ...............................................................................................................................................15
PERFORMANCE PARTS............................................................................................................................................ 17
TROUBLESHOOTING.................................................................................................................................................18
NOTES..........................................................................................................................................................................21
SERVICE VIDEOS ..................................................................................................................................................... 23

MAINTENANCE
3Corn Head Clinic Guide -GT
MAINTENANCE
Themaintenance items in this section outlines the recommended intervals and lubricants required to keep the
corn head functioning properly.
For more information on maintenance items and repairs please refer to your Operators Manual or the Drago
Service Video website at https://www.dragotec.com/service-video
It is important to use only the lubricants specified or degradation of corn head performance may appear over
time. Unlike most other EP0 greases, Mobilux EP0 grease does not use clay or polymers as the base material.
When clay-based greases are used over time the grease evaporates and leaves behind the base material. This base
material deposit can build up over time preventing normal operation. This is the common cause of deck plates and
gathering chain tensioners to stick. The pictures below show what the base material deposits look like.

MAINTENANCE
Corn Head Clinic Guide -GT
4
REQUIRED FLUIDS
LUBRICANT PART NUMBERS
-Intermediate Gearbox
-Row Unit Gearbox (Non-Chop)
-Row Unit Gearbox (Single Chop)
-Row Unit Gearbox (Twin Chop+)
-Cross-Auger Gearbox
-Heavy-Duty Drive Gearbox
GR-1000T
–SAE 30W Oil
Mobilux EP 0 Grease
-Gathering Chains
-Stalk Rollers
-Gathering Chain Tensioner
-Gathering Chain Drive Sprocket
-Gathering Chain Idler Sprocket
-Folding Joints
-Jack Shaft Bearings
-PTO U-Joints
-PTO Shield Bearing
-Cross-Auger Slip Clutch
–
–
–
–
–
–
–
–
–
Mobil SHC 634 Oil
47 oz (1.4L)
98 oz (2.9L)
179 oz (5.3L)
193 oz (5.7L)
85 oz (2.5L)
71 oz (2.1L)
LUBRICANT LOCATION CAPACITY
Mobilux EP 0 Grease 14 oz (414mL) Tube –Case of 10
Mobil SHC 634 Oil
Quart (0.9L) –Single
Case –12 Quarts
5 Gallon Bucket (19L)
DR-MOB634-QT
DR-MOB634-CASE
DR-MOB634-5GAL
LUBRICANT
SIZE
PART NUMBER

MAINTENANCE
5Corn Head Clinic Guide -GT
MAINTANCE SCHED ULE
PRE-SEASON
NORMAL OPERATION
CHECK
-Heavy-Duty Gearbox Oil Levels
-Intermediate Gearbox Oil Levels
-Row Unit Gearbox Oil Levels
-Cross-Auger Gearbox Oil Levels
-Deck Plate Gaps
ADJUST
-Gathering Chain Tensioners
LUBRICATE -Gathering Chain Tensioners
-Stalk Rollers
EVERY 20 HOURS
CHECK
-Chopping Knives
LUBRICATE
-Stalk Rollers
-Folding Tow Shaft Couplers
EVERY 100 HOURS
CHECK
-Heavy-Duty Drive Gearbox Oil Levels
-Intermediate Gearbox Oil Levels
-Row Unit Gearbox Oil Levels
-Cross-Auger Gearbox Oil Levels
-Gathering Chain Tensioners
ADJUST
-Clean Deck Plates
LUBRICATE
-Jack Shaft Bearings
-Gathering Chain Tensioners
-Gathering Chain Drive Sprockets
-Gathering Chain Idler Sprockets
-PTO U-joints
-PTO Shield Bearings
EVERY 250 HOURS OR ANNUALLY
IF PERFORMING ANNUAL MAINTENANCE,COMPLETE THE 20,AND 100-HOUR SERVICES,IN
ADDITION TO THE 250-HOUR SERVICE
CHECK
LUBRICATE
-Inspect Gathering Chain Wear Guides
-Oil Gathering Chains
-Folding Joints
-Cross-Auger Slip Clutch(s)

MAINTENANCE
Corn Head Clinic Guide -GT
6
DOWN CORN
DAILY
CHECK -Chopping Knives
-Gathering Chain Tensioners
LUBRICATE
-Folding Tow Shaft Couplers
EVERY 100 HOURS
CHECK
-Heavy-Duty Drive Gearbox Oil Levels
-Intermediate Gearbox Oil Levels
-Row Unit Gearbox Oil Levels
-Cross-Auger Gearbox Oil Levels
ADJUST
-Clean Deck Plates
LUBRICATE
-Jack Shaft Bearings
-Gathering Chain Drive Sprockets
-PTO U-joints
-PTO Shield Bearings
EVERY 250 HOURS OR ANNUALLY
IF PERFORMING ANNUAL MAINTENANCE COMPLETE THE DAILY, 20,AND 100-HOUR SERVICES,IN
ADDITION TO THE 250-HOUR SERVICE
CHECK
LUBRICATE
-Inspect Gathering Chain Wear Guides
-Oil Gathering Chains
-Folding Joints
-Cross-Auger Slip Clutch(s)
EVERY 20 HOURS
-Stalk Rollers
-Gathering Chain Idler Sprockets
-Gathering Chain Tensioners
LUBRICATE

MAINTENANCE
7Corn Head Clinic Guide -GT
PRE-SEASON
①Check Heavy-Duty Gearbox Oils
② Check Intermediate Gearbox Oils
③ Check Row Unit Gearbox Oils
④ Check Auger Gearbox Oils
⑤ Check Deck Plate Gaps
⑥Adjust Gathering Chain Tension
⑦Grease Gathering Chain Tensioner
⑧ Grease Stalk Rollers

MAINTENANCE
Corn Head Clinic Guide -GT
8
20-HOUR
100-HOUR
① Inspect Chopper Knives
② Grease Stalk Rollers
③ Grease Folding Tow Shafts
① Check Heavy-Duty Gearbox Oils
② Check Intermediate Gearbox Oils
③ Check Row Unit Gearbox Oils
④ Check Auger Gearbox Oils
⑤Check Gathering Chain Tension
⑦ Clean Under Deck Plates

MAINTENANCE
9Corn Head Clinic Guide -GT
100-HOUR (Cont.)
250-HOUR OR YEARLY
If performing year end service complete the 20, and 100-hour services in addition to the 250-hour service below.
⑧ Grease Jackshaft Bearings
⑨Grease Gathering Chain
⑩ Grease Gathering Chain Drives
⑪ Grease Gathering Chain Idlers
⑫ Grease PTO Shaft U-Joints
⑬ Grease PTO Shaft Shield
① Inspect Gathering Chain Guides
② Oil Gathering Chains
③ Grease Folding Tow Joints

MAINTENANCE
Corn Head Clinic Guide -GT
10
250-HOUR OR YEARLY (Cont.)
④ Grease Cross-Auger Slip

INITIAL SETTINGS
11 Corn Head Clinic Guide -GT
INITIAL SETTINGS
The settings listed in this section are the suggested settings to be used when starting each harvest season.
Adjustments can then be made to best suit the conditions being operated in. The head angle and head speed are
the most critical to maintaining performance of the corn head. Before going to the field each year all settings
shown should be checked to verify that the head is set properly.
CORN HEAD ANGLE
The corn head angle is measured from the deck plates and should be
between 17°and 23°for non-chopping heads and 21°to 23° for chopping
heads.
-For normal operation the recommended setting is 20°-21°
-For down corn the recommended setting is 23°
To check the head angle, park the combine with the corn head attached,
on a flat, level surface,and place the corn head in operating position.
Place an angle finder on the deck plates to check the angle.
Whenever the corn head angle is adjusted the snout angle should be
adjusted as well.
See Section 6.1 in the Operators Manual for further information.

INITIAL SETTINGS
Corn Head Clinic Guide - GT
12
HEAD SPEED
Excessive butt shelling and poor feeding can occur from the head being operated either TOO FAST or TOO
SLOW. The speed that the corn head operates is critical to maintain proper performance with the Drago corn
head. Any time the head is adapted to fit a different combine, the gearing should be checked to verify it is
correct. Contact your dealer to determine the correct gearing for your combine.
The corn head should be operated in the 630-700rpm range. The recommended initial speed is 650-675rpm.
Changes can be made to this speed to suit different conditions.
Use the formula below to determine the correct combine feeder house speed for the desired head speed.
Please note that some combines do not display the actual feeder output speed in the cab. If this is encountered
the best practice is to use a hand tachometer on the output shaft of the feeder house.
  =
    
 
Example:
A Gleaner S88 combine with a variable speed feeder house drive. The monitor in the cab is showing 510 rpm
feeder speed.
-This model of combine requires a 1.5 multiplier be added to the in-cab feeder speed reading due to the
feeder speed being monitored at a different point in the system.
o   =5101.5
oActual feeder speed for this example is 765 rpm.
-Determine which driveR and driveN gears are currently installed on the corn head.
oThe driveN gear on the heavy-duty gear drive is always 30-tooth. Only the driveR gear is
changed.
oFor this example, the driveR is a 26-tooth gear and the driveN is a 30-tooth gear.
  =
765 26 ℎ
30 ℎ
This works out to 663rpm actual head speed.

INITIAL SETTINGS
13 Corn Head Clinic Guide -GT
SNOUT ADJUSTMENTS
When positioning the snouts do not place them below the breakover line. This line extends from the bottom
surface of the bonnet forward toward the wear point. If the snouts are below this point and an obstacle is
encountered, they will be more likely to fold under the corn head instead of floating over top of the obstacle.
See Section 6.2 in the Operators Manual for specific adjustment procedures.
DECK PLATE GAP
Check the deck plate gap using tool ST-8 which is available from your
local Drago dealer. Place the tool where the curved portion of the deck
plate stops.
-Insert the tool until the tab marked “MIN_F” is between the deck
plates. The deck plates should not move, or,move very slightly
when the tool is inserted.
-Insert the tool to the tab marked “MAX_F” is between the deck
plates. The deck plates should spread to the maximum setting
and should not be able to be opened further.
If adjustment is required see Section 6.6 in the Operators Manual.
Correct
Incorrect

INITIAL SETTINGS
Corn Head Clinic Guide - GT
14
DECK PLATE TENSION
Deck plate tension can be checked by seeing if the two adjusting bolts are
approximately centered between the two lines on the cover plate.
If adjustment is required see Section 6.6 in the Operators Manual.
GATHERING CHAIN TENSION
Check the gathering chain tension by pulling on the side of the gathering
chain until the tensioning fork hits the internal stop. Mark the tensioning
fork shaft and release the chain. The tensioning fork should have 1/4" to
5/16“of travel.
If adjustment is required see Section 6.7in the Operators Manual.

PART REPLACEMENT
15 Corn Head Clinic Guide -GT
PART REPLACEMENT
The information below is intended to help evaluate when certain wear parts are nearing the end of their
intended lifespan. Dragotec recommends only original OLIMAC wear parts be used. Use of third-party parts may
void warranties and have been shown to have a shorter wear life.
Stalk Roller Knives
The stalk roller knives are due to be replaced when visible wear is seen on the front edge of the knife blade
approximately 5-6 inches back. The front edge of the roller knives should be inspected to see if wear has
progressed past the tungsten coated edge.
It is not recommended to flip the stalk roller knives. This may cause material to become wrapped around the
rear of the stalk roller damaging the stalk roller seal.
Visible
Wear Limit
Tungsten
Edge Wear

PART REPLACEMENT
Corn Head Clinic Guide -GT
16
Gathering Chains
The gathering chains should be replaced when they reach 3% stretch. Continuing to run past this point can cause
the chains to break and potentially enter the combine. Measure the amount of exposed tensioner tube
(highlighted area). This dimension should be 213/16” or less.
Deck Plates
The deck plates can become worn over time causing material to hairpin on sharp edges impeding feeding. The
wear is typically concentrated on the vertical edge that contacts the crop on the front curve (highlighted area).
When this vertical edge becomes thin the deck plates should be replaced.
Wear
Location
2 13/16”

PERFORMANCE PARTS
17
Corn Head Clinic Guide - GT
PERFORMANCE PARTS
Drago offers several different product performance parts and accessories for different conditions. The two
shown below are considered to provide the best performance increase across the widest range of conditions.
SNOUT WEAR POINTS
In 2018, Drago introduced a new standard poly wear point for GT corn heads with a new front profile.
-The standard wear point has a shorter, less aggressive profile, with a higher tip point to help reduce the
risk of folding the snouts under.
-The aggressive wear point has a pointed tip that sits low to the ground and is recommended for severe
down corn conditions where the wear point tries to ride up over the corn.
The picture below shows the difference in the wear points. The yellow is the aggressive wear point, and the
green is the standard wear point.
AGGRESSIVE GATHERING CHAINS
All Drago GT heads can be optioned from the factory with an optional aggressive gathering chain. Heads may be
optioned with aggressive chains on either the center 4 rows, or across the whole head. The aggressive gathering
chain uses a longer lug as compared to the standard chain. The longer lug allows for less open space near the
top of the row unit. This provides a more positive action to help push material into the cross-auger.
The aggressive gathering chain can be added to any existing GT head. On 2016 built corn heads an additional
modification is required. Refer to Product Bulletin PB-2016.2 for more information.

TROUBLESHOOTING
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18
TROUBLESHOOTING
EXCESSIVE
TRASH
Remove Ear Savers
Stalks Breaking at Front
of Row Unit
Stalks Breaking at
Middle of Row Unit
Stalks Breaking at Rear
of Row Unit
Deck Plate Gap Too
Tight
Check deck plate minimum
gap vs average stalk size.
Deck Plate Pressure
Too High
Reduce deck plate pressure.
Move the adjustment bolts
closer to the outer line.
Check Head Speed
Adjust tow shaft speed
between 630-700rpm to see
if the condition improves.
Ears Tumbling at Rear of
Row Unit
Install aggressive gathering
chains.
Head Speed Too Low
Increase tow shaft speed.
Tow shaft speed should be
between 630-700rpm.
Ground Speed Too High
Decrease ground speed. The
stalk should be completely
processed before it reaches
the rear of the row unit.
Check Stalk Roller Gap
Stalk roller knife gap should
be 3-4mm (1/8”) at the front
and 0-1mm at the back.
Check Head Angle
Increase head angle to 23°
to reduce trash. If
unsuccessful reduce head
angle to 17°(non-chopping)
or 21°(chopping) to allow
for better flow.
Install Aggressive
Gathering Chains
Install Corn Reel

TROUBLESHOOTING
19 Corn Head Clinic Guide -GT
FEEDING
Perform Fluff Test
Does material break apart
easily by hand?
Combine Back Feeding Clean Dry Ears
Check Feeder Speed
Increase speed to carry
away material if feeder
house shelling is not an
issue. Slow down speed if
shelling in the feeder house.
Check Corn Head Angle
Decrease head angle to
allow better material flow.
Minimum deck plate angle is
17°(non-chopping) or 21°
(chopping).
Install Aggressive
Gathering Chains
Check Feeder Drum
Ensure combine feeder
drum is in the corn position.
Install Drago feeder house
drum blocks Case IH
combines.
Check Combine Settings
-Concave Setting
-Concave Type
-Rotor Speed
-Rotor Cage Vane (some
combines)
Increase Feeder Speed
Increase combine feeder
speed while maintaining the
same ground speed. Do not
exceed maximum head
speed. Refer to the Head
Speed section to determine
the maximum combine
feeder speed.
Feeder Speed Too Slow
Increase tow shaft speed to
700 rpm or faster.
Install Fluff Fingers
Check Corn Head Angle
Increase deck plate angle to
reduce trash. If unsuccessful
reduce deck plate angle to
allow better flow. Deck
plate angle range is 17°to
23°(non-chopping) or 21°to
23°(chopping).
Install Corn Reel
Install Aggressive
Gathering Chains