1993/12/01 Caterpillar

Caterpillar uses Castrol Tarp, Tarp-B and 4164 as the rust preventative on many of the new and remanufactured parts in the parts system. This article is intended to help answer many of the questions we have received about these products.

Castrol Tarp And Tarp-B

Castrol Tarp is a general rust preventative and preservative. It is used on parts such as crankshafts and engine blocks. Castrol Tarp-B is similar, except it has a blue color. The color helps obtain a uniform film thickness during a manual spray operation. On preserved parts, the blue color can disappear over time. Tarp and Tarp-B are all-purpose, self-healing, rust preventives. Tarp and Tarp-B have the following characteristics:

* Can be applied by brush, dip, or spray.

* Are thixotropic, which means that if agitated, they will change from a gel to a liquid, and then if let stand, they will gel.

* Normal applications have 4 to 11 mil (.004 to .011 in) film thickness.

Tarp and Tarp-B offer the following protection:

* Withstands 5 percent salt spray for 1000 hours.

* Withstands unsheltered ocean trips of 45 days.

* Protects in all types of weather for 2 years.

* Protects indoors for 3 to 5 years.

Tarp and Tarp-B should be removed prior to part use to ensure that:

* No dust or dirt remains.

* Small passages will not be temporarily restricted.

* Mating surfaces will seat properly.

Tarp and Tarp-B can be removed from unpainted surfaces, with 60°C (140.0°F) water and mild soap or alkaline cleaner. A 4100 kPa (600 psi) spray is effective at lower water temperatures. Do NOT use steam, because it will cause the Tarp or Tarp-B to harden. Be sure to use proper safety equipment when cleaning. If the part will not be immediately used, it should be blown dry and covered with light oil to prevent rust.

To remove Tarp and Tarp-B from a painted surface, use a cleaner with enough strength to insure adequate removal, yet mild enough to prevent damage to the underlying paint. Cleaning solutions with a PH of less than 9 are usually workable. The following process is recommended:

1. Spray with Castrol LT-10® (or equivalent), through a non-atomizing nozzle.

2. Allow Tarp film to soften for 15 minutes.

3. Remove the film with a 2 to 4 percent Castrol Lift-Off® solution (or equivalent) at 82°C (180°F). Use a high pressure spray gun equipped with a spade nozzle, held 6 to 12 inches from the part.

4. Completely rinse with clear water.

Castrol 4164

Castrol 4164 is a derivative of Tarp. Its characteristics differ from Tarp and Tarp-B in that Castrol 4164 has lower viscosity and is usually applied in film thickness of only 2 mil (.002 in). Castrol 4164 offers the following protection:

* Protects in all types of weather for 8 months.

* Protects indoors for a minimum of 3 years.

Castrol 4164 is the preferred preservative for engine cylinder heads, enging cylinder liners and engine cylinder kits. It can be distinguished from Tarp or Tarp-B by its lower viscosity and thinner film thickness. If the engine cylinder liners and engine cylinder liner kits, protected with 4164, are free of debris, they do not need to be cleaned prior to installation in an engine. However, if there are puddles of 4164, the puddles should be removed with a clean shop towel. Tests have indicated that 4164 has adequate lubricity and is compatible with engine oil, coolant, and rubber seals. The test also indicate 4164 does not leave any trace in the combustion chamber after the engine is run.

If the part has collected debris, it can be cleaned with 60°C (140.0°F) water and mild soap or alkaline cleaner. A 4100 kPa (600 psi) spray is effective at lower water temperatures. Do NOT use steam, because it will cause the 4164 to harden. Be sure to use proper safety equipment when cleaning.

Product Availability

Castrol Tarp, Tarp-B, 4164, LT-10, and Lift-Off are manufactured by: