91308-ZV5-821 Honda O-RING (Honda Code 4594842).

Do not operate or work on this engine unless you have read and understand the instructions and warnings in the Operation and Maintenance Manual. Failure to follow the instructions or heed the warnings could result in injury or death. Contact any Caterpillar dealer for replacement manuals. Proper care is your responsibility.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, PERJ1017, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat® products.Dispose of all fluids according to local regulations and mandates.
Specifications
Table 1
Check Fuel API
The acceptable range of the fuel API is 30 to 45 API @ 15° C (59° F) Introduction
This test checks for problems regarding fuel quality. Refer to Diesel Fuels and Your Engine, SEBD0717 for more details.References
Reference: Special Publication, PERJ1017, "Dealer Service Tool Catalog"Reference: Operation and Maintenance Manual, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations", "Fuel Recommendations"Reference: Tool Operating Manual, NEHS0607Required Tools
Illustration 1 g06495073
9U-7840 Fluid and Fuel Calibration Gp
Table 2
Required Tools
Item Quantity Part Number Description
T1 1 9U-7840 Fluid and Fuel Calibration Gp
T1a 1 9U-7839 STOPWATCH
T1b 1 1P-7438 Beaker
T1c 1 5P-2712 Thermometer/Hydrometer
T1d 1 1P-7408 Thermometer/Hydrometer
T1e 1 9U-7842 Beaker
T1f 1 4C-3975 Plastic Case
T1g 1 9U-7841 Cup
T2 1 9U-7917 Battery Test Preparation
Remove all covers to expose the fuel system.Test Procedures
Use the following procedure to test for problems regarding fuel quality:
Determine if water and/or contaminants are present in the fuel. Check the water separator (if equipped). If a water separator is not present, proceed to Step 2. Drain the water separator, if necessary. A full fuel tank minimizes the potential for overnight condensation.Note: A water separator can appear to be full of fuel when the water separator is full of water.
Determine if contaminants are present in the fuel. Remove a sample of fuel from the bottom of the fuel tank. Visually inspect the fuel sample for contaminants. The color of the fuel is not necessarily an indication of fuel quality. However, fuel that is black, brown, and/or similar to sludge can be an indication of the growth of bacteria or oil contamination. In cold temperatures, cloudy fuel indicates that the fuel may not be suitable for operating conditions. The following methods can be used to prevent wax from clogging the fuel filter:
Fuel heaters
Blending fuel with additives
Utilizing fuel with a low cloud point such as keroseneRefer to Operation and Maintenance Manual, SEBU6251, "Caterpillar Commercial Diesel Engine Fluids Recommendations", "Fuel Recommendations" for more information.
Check fuel API with a 9U-7840 Fluid and Fuel Calibration Gp for low-power complaints. The acceptable range of the fuel API is 30 to 45 when the API is measured at 15° C (59° F), but there is a significant difference in energy within this range. Refer to Tool Operating Manual, NEHS0607 for API correction factors when a low-power problem is present and API is high.Note: A correction factor that is greater than "1" may be the cause of low power and/or poor fuel consumption.
If fuel quality is still suspected as a possible cause to problems regarding engine performance, disconnect the fuel inlet line. Temporarily operate the engine from a separate source of fuel that is known to be good. This procedure will determine if the problem is caused by fuel quality. If fuel quality is determined to be the problem, drain the fuel system and replace the fuel filters. Engine performance can be affected by the following characteristics:
Cetane number of the fuel
Air in the fuel
Other fuel characteristics