JLG TH336 User manual

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February 16, 2011
ATTENTION: This notice is being issued to advise you of the requirement to update certain
Caterpillar (“CAT”) Telehandlers that were manufactured by JLG Industries,
Inc. (“JLG”). This program must be completed as soon as possible on all
affected machines.
PROBLEM:
When the fork tilt up function is continuously held and the tilt cylinder reaches end of stroke and
then the lift up function is activated while continuing to activate fork tilt up, a void in the barrel
end of the lift cylinder is created. As a result of this void, when lift up or down is initiated, the
boom will drop in an uncontrolled manner until the void is filled with hydraulic oil.
In has recently been determined that the load charts on certain CAT Model TH336, TH337,
TH406 and TH407 telehandlers do not have the correct load values. Lifting certain loads
specified on those load charts will cause the machine to tip-over.
This bulletin requires the installation of a compensating valve kit in order to eliminate the
possibility of a void being created in the lift cylinder or the replacement of the load charts or both
on all affected machines.
AFFECTED PRODUCTS:
This issue affects certain CAT Telescopic Material Handler Models TH336, TH337, TH406 and
TH407 having the following Serial Numbers.
Model Affected Serial Number(s)
GROUP A
Load Chart Book Replacement & Compensating Valve Kit Installation Procedure
TH336 TDE00102, 104-116, 118-134, 136, 138-139, 141, 143, 145-147, 149-
150, 152-154, 157.
TH337 TDF00101-103, 105-184, 186, 189-193, 195, 198.
SERVICE LETTER
Reference: #
C
1
1
1C
3
SAFETY PRODUCT IMPROVEMENT PROGRAM FOR THE INSTALL
A
TION
OF A HYDRAULIC COMPENSATING VALVE OR LOAD CHART
REPLACEMENT OR BOTH ON CERTAIN CAT MODEL TH336,
TH337, TH406 AND TH407 TELEHANDLERS.
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TH406
TBX00102-105, 107, 114, 119, 121, 123-126, 128-129, 131-136, 145-
149, 151, 154, 158, 161, 163-168, 171-175, 177-199, 201-205, 207-208,
210, 212, 215, 217, 219-221, 223-224, 228, 237, 240-241, 244-254, 257,
259, 263, 265, 271-272, 275, 277-278, 280-282, 285-286, 289-290, 295,
299-300, 302-307, 312-330.
TH407
TBY00101, 103, 105-109, 111-114, 116-174, 177-200, 202-224, 232-262,
265-268, 270-280, 283-287, 290-299, 301-305, 307-324, 326-328, 331,
333-336, 338-343, 345-346, 348-359, 361-362, 364-383, 385, 388, 390,
391-392, 394, 396-402, 404-408, 410-413, 415, 417-418, 421-423, 425-
431, 433-437, 439-442, 444-445, 447, 449-452, 454, 456-461, 463-467,
469-471, 473-480, 482-484, 486-488, 490-491, 493, 495-498, 500-504,
516-524, 526-527, 530-534, 537-538, 540-547, 550-551, 554-557, 560-
561, 566-573, 575-582, 584-587, 589-592, 594-600, 602-603, 605-606,
608-615, 617-632, 635, 637, 639, 641, 644, 653.
Model Affected Serial Number(s)
GROUP B
Compensating Valve Kit Installation Procedure
TH336 TDE00101, 103, 117, 137, 140, 142, 148, 155, 158, 160, 162-169, 171-
173, 175-187.
TH337 TDF00199, 201, 204-212.
TH406 TBX00118, 169, 331-332, 336-341, 343-349.
TH407 TBY00115, 525, 529, 558-559, 562-565, 574, 583, 616, 633-634, 636,
647, 649, 651-652, 654-664, 666, 668-738, 741, 746-747.
PARTS NEEDED:
Reference the above affected Serial Numbers Groups. Each Group will require the
accomplishment of a different procedure and the appropriate kits must be ordered for each
affected unit. The following parts must be ordered to accomplish this update:
For GROUP A UNITS Only:
Model Quantity Part Number Description
1 361-4174 Compensating Valve Kit
TH336 1 337-5091 Load Chart Kit
1 361-4175 Compensating Valve Kit
TH337 1 337-5092 Load Chart Kit
1 361-4174 Compensating Valve Kit
TH406 1 332-9697 Load Chart Kit
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1 361-4175 Compensating Valve Kit
TH407
1 326-1977 Load Chart Kit
For GROUP B UNITS Only:
Model Quantity Part Number Description
TH336 & TH406 1 361-4174 Compensating Valve Kit
TH337 & TH407 1 361-4175 Compensating Valve Kit
ACTION REQUIRED:
GROUP A UNITS
Remove the existing load chart book located in the cab and replace with the revised
load chart. Destroy and discard the original load chart booklet.
The Compensating Valve Kit must be installed on all affected units in accordance
with the enclosed Compensating Valve Kit Installation Procedure.
GROUP B UNITS
The Compensating Valve Kit must be installed on all affected units in accordance
with the enclosed Compensating Valve Kit Installation Procedure.
SERVICE CLAIM ALLOWANCES:
To receive reimbursement, file a service claim through the normal CAT service claims process.
When filing this claim through the CAT system, please use the following codes in the
appropriate input fields: Input Field Before Failure
Part Causing Failure C111C3
Group Number 5086
Warranty Claim Description 56
SIMS Description Code T
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The reimbursement terms of this program are as follows:
Caterpillar Dealer Suggested Customer Suggested
Parts % Labor Hrs % Parts % Labor Hrs % Parts % Labor Hrs %
100% 100% 0% 0% 0% 0%
Labor Time:
Compensating Valve installation is a 1.5 hour job.
Load Chart installation is a 0.5 hour job.
Up to 2 hours and 100 km for travel.
PARTS DISPOSITION:
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
CONTACTS:
A copy of this Service Letter will be available on the CAT Alliance Group website. If you have
any questions or need further information, please contact CAT Alliance Product Support.
Enclosures:
Compensating Valve Kit Installation Procedure
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PROCEDURE: Hydraulic Compensating Valve Installation
MODEL: CAT TH336, TH337, TH406 and TH407 Telehandlers
Kits Parts Breakdown:
• Telehandler Model TH336 & TH406, Kit # 361-4174
P/N in Kit Qty in Kit Description
353-3455 1 Hydraulic Valve
298-0462 1 Hydraulic Straight Adapter
303-4754 3
Hydraulic 90 degree Adapter
353-3454 1 Bracket
297-7091 2 HexHead Bolt
8T-4224 4 Washer
5C-7261 2 Nut
343-7049 2 Hose Clamp
353-3448 1 Hose Assembly
353-3451 1 Hose Assembly
353-3450 1 Hose Assembly
353-3449 1 Hose Assembly
342-3862 3 Cable Tie
• Telehandler Model, TH337 & TH407, Kit # 361-4175
P/N in Kit Qty in Kit Description
353-3455 1 Hydraulic Valve
298-0462 1
Hydraulic Straight Adapter
303-4754 3
Hydraulic 90 degree Adapter
353-3454 1 Bracket
297-7091 2 HexHead Bolt
8T-4224 4 Washer
5C-7261 2 Nut
343-7049 2 Hose Clamp
353-3448 1 Hose Assembly
353-3451 1 Hose Assembly
353-3452 1 Hose Assembly
335-3453 1 Hose Assembly
353-3862 1 Cable Tie
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CAUTION: USE ALL APPLICABLE SAFETY PRECAUTIONS WHILE
WORKING ON, UNDER OR AROUND ANY MACHINERY.
IMPORTANT! THIS PROCEDURE MUST BE ACCOMPLISHED IN A
CONTAMINANT-FREE ENVIRONMENT. ENSURE THE AREA IS
FREE FROM DIRT AND DEBRIS BEFORE REMOVING ANY
HYDRAULIC COMPONENTS.
IN THE EVENT OF CONTAMINATION CLEAN THE HYDRAULIC
SYSTEM OIL UNTIL THE HYDRAULIC OIL CLEANLINESS FACTOR
MEETS ISO 18/15, NO ADDITIONAL TIME IS INCLUDED IN THIS
PROCEDURE FOR SYSTEM FLUSHING.
Procedure – Hydraulic Compensating Valve Installation:
1. Remove any attachment from the machine.
2. Prepare the machine for servicing by:
a. Park the machine on a firm, level surface with the machine level
b. Retract the boom and elevate the boom to approximately a 33 degree
boom angle.
c. Place the travel select lever in the (N) NEUTRAL position and engage the
parking brake.
d. Position the rod end of the tilt cylinder to the fully extended position.
e. Shut the engine OFF.
f. Properly support the boom.
g. Chock the front and rear wheels of the machine.
3. Remove the hydraulic valve from the kit (P/N 353-3455) and insert adapter (P/N
298-0462,) into the port marked “C2”. Torque the fitting to 55 Nm (41 lb ft).
4. Install the three 90º elbow adapters (P/N 303-4754) into the three remaining
ports of the valve. Torque the fittings to 55 Nm (41lb ft), ensuring the orientation
is as shown in Figure #1.
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5. Apply loctite #243 to the threads of both hex head bolts (P/N 297-7091).
6. Attach hydraulic valve (P/N 353-3455) to the mounting bracket (P/N 353-3454)
as shown in Figure #2, using the two hexhead bolts (P/N 297-7091). A washer
(P/N 8T-4224) must be placed on both the head and nut end of the bolt. Secure
with nut (P/N 5C-7261).
FIGURE #2
7. Measure 570 mm (22-1/2 inches) from the compensation cylinder barrel rod end
and mark the location (refer to Figure #3).
FIGURE #1
Note: Left hand image shows ports marked “V1” and “V2”.
Right hand image shows ports marked “C1” and “C2”.
Secondary ports are uppermost in both images.
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FIGURE #3
8. Using clamps (P/N 343-7049) securely attach the valve and bracket assembly to
the compensation cylinder (Note: the bolts inserted in Step #7 should be on the
left hand side of the valve block when mounted).
9. The left hand side of the valve should be placed to correspond with the mark
made in Step #8. Tighten both clamps with a torque of 4.5 Nm (3.3 lb ft).
10. Remove and discard any cable ties fitted to the compensation cylinder hoses.
11. Prepare to loosen the compensation cylinder hydraulic hoses by placing a drain
pan of suitable size close to the work area. Oil discharge will be less than 1 litre
(1/4 gallon).
12. Carefully loosen the compensation cylinder hoses, attached to the hydraulic pipe
mounted on the underside of the boom, allowing any trapped pressure to relieve.
Allow oil to drain into a suitable receptacle then remove both hoses completely
from the cylinder, destroy or responsibly discard.
13. Install hose (P/N 353-3448) from the rod end of the compensation cylinder to
valve port marked “V1”. Correctly torque the hose fitting to 55 Nm (41lb ft).
14. Re-orientate the fitting located at the non-rod end of the compensation cylinder
(refer to Figure #4). Install hose (P/N 353-3451) from valve port marked “V2” to
this fitting. Correctly torque the hose fitting to 55 Nm (41 lb ft).
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FIGURE #4
15. Install hoses as follows:
a. (TH336 and TH406 only)
Using hose (P/N 353-3450) connect valve port marked “C1” to the inner
boom hydraulic pipe and hose (P/N 353-3449) from the outer boom
hydraulic pipe to valve port marked “C2”. Correctly torque the hose fittings
to 55 Nm (41 lb ft).
b. (TH337 and TH407 only)
Using hose (P/N 353-3453) connect valve port marked “C1” to the inner
boom hydraulic pipe and hose (P/N 353-3452) from the outer boom
hydraulic pipe to valve port marked “C2”. Correctly torque the hose fittings
to 55 Nm (41 lb ft).
16. Ensure the outer face corners of the hydraulic valve block are spaced the same
distance from the boom. If necessary adjust positioning of the valve until correct
position is achieved. Ensure the clamps installed in Step #8 are secure.
17. Using four cable ties (three on TH337 and TH407) fix both boom hoses to the
boom hydraulic pipe as shown in Figure #5.
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FIGURE #5
18. Confirm installation is correct as shown in Figure #6.
FIGURE #6
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19. Remove supports and any tools from the work area. Verify the oil level is correct.
Perform a complete function check in accordance with the Operation and
Maintenance Manual, and confirm safe and proper operation of all functions.
Pay particular attention to check for leaks from the new installation.
20. Perform the Hydraulic Compensating Valve function verification procedure:
a. In an area free from obstructions and personnel, Position the rod end of
the tilt cylinder to the fully extended position.
b. While continuing to operate the tilt function, raise the boom approximately
1.5m (59 inches).
c. Release the tilt function and operate boom lower, the boom should lower
in a controlled manner.
21. The unit may be returned to service once proper operation is confirmed.
Should any further discrepancies be discovered during the accomplishment of this
procedure, please contact your CAT Alliance Product Support Manager immediately for
further evaluation.
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