885526120 Mercury SCREW, (M8 x 120)

The information provided are the latest recommendations for the Caterpillar diesel engines that are covered by this Special Publication. This information supersedes all previous recommendations which have been published for the Caterpillar diesel engines that are covered by this Special Publication. Special fluids are required for some engines and continued use of these special products will be necessary. Refer to the applicable Operation and Maintenance Manual.This publication is a supplement to the Operation and Maintenance Manual. This publication does not replace the engine-specific Operation and Maintenance Manuals.
These recommendations are subject to change without notice. Consult your local Cat dealer for the most up to date recommendations.
In order to avoid potential damage to your Cat machine and/or Cat engine, only purchase Cat fluids and Cat filters through your Cat dealer or Cat authorized outlets. For a list of authorized Cat parts outlets in your area, consult your Cat dealer.If you purchase what appear to be Cat fluids and/or Cat filters through other outlets/sources, you are at a very high risk of purchasing counterfeit (“look-alike”) products.Counterfeit or “look-alike” products may visually appear the same as the original Cat product, but the product performance and internal quality will typically be very low.Counterfeit or “look-alike” products have a very high likelihood of causing and/or allowing engine and/or machine compartment damage.
Many of the guidelines, recommendations, and requirements that are provided in this Special Publication are interrelated. Before using the provided information, it is the responsibility of the user of this Special Publication to read and understand the information provided in its entirety.It is the responsibility of the user of this Special Publication to follow all safety guidelines found in this Special Publication and in engine and/or machine specific Operation and Maintenance Manual when performing all recommended and/or required engine, engine systems, and/or machine maintenance.For questions concerning the information presented in this Special Publication and/or in your product Operation and Maintenance Manual, and/or for additional guidelines and recommendations (including maintenance interval recommendations/requirements) consult your Cat dealer.
Follow all industry standard safety practices when operating engines and/or machines and when performing all recommended and/or required maintenance.
Commercial products that make generic claims of meeting “Cat” requirements without listing the specific Cat recommendations and requirements that are met may not provide acceptable performance. Commercial products may cause reduced engine and/or machine fluid compartment life. Refer to this Special Publication and refer to product specific Operation and Maintenance Manual for Cat fluids recommendations and requirements.
Note: Instructions for the installation of the filter are printed on the side of each Caterpillar spin-on filter. For nonCaterpillar filters, refer to the installation instructions that are provided by the supplier of the filter.
In order to meet expected fuel system component life, 4 micron(c) absolute or less secondary fuel filtration is required for all Cat diesel engines that are equipped with common-rail fuel systems. Also, 4 micron(c) absolute or less secondary fuel filtration is required for all Cat diesel engines that are equipped with unit injected fuel systems. For all other Cat diesel engines (mostly older engines with pump, line and nozzle type fuel systems), the use of 4 micron(c) absolute or less secondary fuel filtration is strongly recommended. Note that all current Cat diesel engines are factory equipped with Cat Advanced Efficiency 4 micron(c) absolute fuel filters.In order to obtain additional information on Cat designed and produced filtration products, refer to the “Reference Material” article, “Filters” and “Miscellaneous” topics in this Special Publication. Consult your Cat dealer for assistance with filtration recommendations for your Cat machine.
Caterpillar does not warrant the quality or performance of non-Caterpillar fluids and filters.
Diesel Fuel and Injector Health
Fuel injectors are highly engineered components built with very tight clearances and designed to spray precise amounts of fuel into the combustion chamber. The accurate operation of the fuel injectors supports the performance and noise of the engine and impacts the emissions.Fuels that are not per the characteristics described in this chapter and in the recommended specifications can lead to deposits in the injector, cold start issues, smoke, noise, low performance, increased emissions, and other issues.Deposits in the injector can be external or internal:
External deposits form on the tip of the injector. These deposits become carbonaceous (mainly composed of carbon) due to the high temperature of the combustion chamber. The deposits prevent the appropriate fine spray of the fuel and the proper atomization in the combustion chamber. These issues can significantly degrade the operation of the engine.
Internal deposits form on the internal moving components of the injector. These deposits close the tight clearances in the injector and prevent the components from moving as designed. Some internal deposits can be “soaps” that form due to reaction of sodium contaminants in the fuel with certain fuel additives. Sometimes, these soaps cause injector sticking in the open or closed positions. The result is a malfunction of the injector.Cleanliness of the injectors impact the performance, power, fuel consumption, and emissions throughout the life of modern diesel engines. To keep the injectors clean, avoid injector deposits and ensure appropriate operation and long life of the injectors:
Ensure that the fuel has the proper chemistry. Fuels that are per the specifications