- Wheel Tractor-Scraper:
- 621G (S/N: DBB1-267)
- 623G (S/N: DBC1-231)
- 627G (S/N: DBD1-332)
- 623G (S/N: DBC1-231)
Introduction
This technical information bulletin replaces a technical information bulletin that was written on 14April 2006. The title of the former technical information bulletin is "The Breather Hole in 7T-7706 Housing As is Not Drilled To the Correct Depth". Disregard the former technical information bulletin. Refer to the following technical information bulletin.
Problem
The breather hole in the 7T-7706 Housing As is not drilled to the correct depth. Improper ventilation causes pressurization of the retarder housing, and this forces transmission oil into the engine. This condition may be improperly diagnosed as seal failure for 2S-6498 Seal Ring in the retarder housing.
Solution
Repair 7T-7706 Housing As with the procedure below.
ReferenceRefer to the appropriate manual for the following procedures for 621G and 623G:
- Disassembly And Assembly, RENR7497, "Retarder And Bearing Cage (Drive Shaft) - Remove"
- Disassembly And Assembly, RENR7497, "Retarder And Bearing Cage (Drive Shaft) - Disassemble"
- Disassembly And Assembly, RENR7497, "Retarder And Bearing Cage (Drive Shaft) - Assemble"
- Disassembly And Assembly, RENR7497, "Retarder And Bearing Cage (Drive Shaft) - Install"
ReferenceRefer to the appropriate manual for the following procedures for 627G:
- Disassembly And Assembly, RENR7498, "Retarder And Bearing Cage (Drive Shaft) - Remove"
- Disassembly And Assembly, RENR74978, "Retarder And Bearing Cage (Drive Shaft) - Disassemble"
- Disassembly And Assembly, RENR7498, "Retarder And Bearing Cage (Drive Shaft) - Assemble"
- Disassembly And Assembly, RENR7498, "Retarder And Bearing Cage (Drive Shaft) - Install"
Repair Procedure For 7T-7706 Housing As
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| Illustration 1 | g01266774 |
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| Illustration 2 | g01266191 |
Section (AA) | |
Finish drilling a 11.125 mm (7/16) hole in passage (B) .
Note: Make sure that all dirt and debris are cleaned in the retarder housing before assembling.