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HQ 004127

February 11, 1998

RR:IA 004127 ch


TARIFF NO.: 8412.21.0075

David Dixon
Cummins Engine Company
Box 3005
Columbus, Indiana 47202-3005

RE: Tariff classification of an engine brake; Jake brake.

Dear Mr. Dixon:

This is in response to your correspondence identifying a difference in tariff classification between the United States, Canada and Mexico. Pursuant to Article 513(6)(a)(ii) of the North American Free Trade Agreement (NAFTA), the NAFTA Customs Subgroup discussed the classification of an article identified as an engine brake at a meeting convened on October 7, 1997. In view of the discussion, and upon further consideration of the matter in order to make clear the view of the Customs Service, we conclude that the engine brake is classified as set forth in this ruling.


An engine brake is also referred to as a jake brake or an engine retarder. The purpose of this device is to provide additional braking power in order to control vehicle speed. It is designed to be used in vehicles driven by internal-combustion engines. Internal-combustion engines incorporate pistons which move up and down inside cylinders. Usually, the piston is attached to a turning shaft (crankshaft) by means of an articulated (jointed) connecting rod. This assembly converts the linear motion of the piston into a circular motion revolving around the crankshaft.

An internal-combustion engine also incorporates a chain driven shaft fitted with multiple eccentric wheels, which is referred to as a camshaft. The variable motion of the eccentric wheels or "lobes" on the camshaft causes push rods and rockers to open and close valves leading in and out of each cylinder.

An internal-combustion diesel engine employs either a four-stroke cycle or a two-stroke cycle. A stroke is the movement of a piston from one end of the limit of its motion to the other. In the four-stroke cycle, the downward motion of the piston creates a partial vacuum in the cylinder. On this stroke, an intake valve is opened while an exhaust valve is closed. A mixture of gas and air is injected into the chamber. On the second stroke, both valves are closed. As the piston moves upward the mixture is compressed, which elevates the pressure in the chamber. During the third stroke the compressed mixture ignites. The heat produced by this combustion causes the gases to expand, which in turn forces the piston down. The motion generated by the combustion is transmitted from the linear motion of the piston to rotary motion as it is transmitted to the crankshaft. On the fourth stroke, the exhaust valve is opened so that the burned gases escape.

The engine brake consists of cast iron housings (one for each cylinder head). Each housing contains the components for operating two cylinders of the engine. The brake assembly contains two master pistons (one for each engine cylinder) which are designed to trigger two slave pistons. The housings also possess two control valves, a solenoid valve and a lash compensator. The engine brake is installed over the engine cylinders.

The engine brake is electrically controlled by means of dash and clutch switches and connections to the engine. When the brake is "off," the engine cylinders operate normally and the brake is separated from the engine cylinders. The master pistons are above the rocker levers which open the intake cylinder valves. The slave pistons are located above the exhaust valves.

When the engine brake is engaged, the compression of gas and air during the engine's compression stroke proceeds normally until the piston is near top dead center. The compression of the mixture results in a compression braking effect. Just before the compressed mixture ignites the engine brake causes the engine's exhaust valves to open, which allows the pressurized air to escape. As a result, there is no power stroke.

The brake is activated by means of an electric current which causes the solenoid valve in the housing to open. This action causes engine oil to flow into the assembly, which forces the master and slave pistons down. The master pistons are now positioned just above the rocker levers. The slave pistons come to rest just above the exhaust valves.

The rocker arms are pushed upward as the intake valves for the engine cylinders are opened. When the engine brake is engaged, the rocker arms are forced against the master pistons. The master pistons are forced upward, which causes the control valve in the brake assembly to close. As a result, oil is trapped in the brake assembly. The oil pressure rises as the master pistons continue upward. The pressurized oil is forced toward the slave pistons. Under further pressure the oil causes the slave pistons to be pushed down until the exhaust valves open. The open exhaust valves allow compressed air to escape from the cylinders before the fuel mixture ignites. The braking cycle is now complete. Thereafter, the rocker arms travel downward, which allows the oil pressure to return to normal and the exhaust valves to close.


What is the proper tariff classification for the engine brake?


The provisions under consideration are heading 84.12, which provides for other engines and motors, and heading 84.09, which provides for parts suitable for use solely or principally with the engines of heading No. 84.07 or 84.08.

Within heading 84.12, subheading 8412.21 provides specifically for hydraulic power engines and motors: linear acting (cylinders). The Explanatory Note to that heading, Part (B), Item (3), at page 1254, indicates that the subheading includes:

Hydraulic cylinders consisting, for example, of a brass or steel barrel and a piston operated by oil (or other liquid) under pressure applied on one side (single-acting) or on both sides (double-acting) of the piston, the energy of the liquid under pressure being converted into a linear motion. These cylinders are used on machine-tools, construction machinery, steering mechanisms, etc.

The brake assembly incorporates master pistons and slave pistons which are operated by oil under pressure. Engine oil entering the assembly is trapped in the engine brake. The master pistons act as pumps as they force the oil through a passageway to the slave pistons. The slave pistons convert the energy of the oil under pressure into linear motion for the purpose of forcing open the exhaust valves of the engine cylinders. In our view, the brake assembly is composed of components which together comprise a linear acting hydraulic cylinder. Accordingly, it is classifiable in subheading 8412.21.

Section XVI, Note 2, states in pertinent part that:

Subject to Note 1 to this Section, Note 1 to Chapter 84 and Note 1 to Chapter 85, parts of machines (not being parts of the articles of heading No. 84.84, 85.44, 85.45, 85.46 or 85.47) are to be classified according to the following rules:

(a) Parts which are goods included in any of the headings of Chapters 84 and 85 (other than headings Nos. 84.09, 84.31, 84.48, 84.66, 84.73, 84.85, 85.03, 85.22, 85.29, 85.38 and 85.48) are in all cases to be classified in their respective headings.

Engines and motors of heading 84.12 are parts of machines. Applying the terms of the legal note, classification is heading 84.09 is in this case precluded because the engine brake is classifiable in heading 84.12.


In view of the foregoing, the engine brake is classified as a linear acting hydraulic cylinder of subheading 8412.21.0075, Harmonized Tariff of the United States (HTSUS), which provides for other engines and motors, and parts thereof: hydraulic power engines and motors: other: other. If the product is the subject of a claim for NAFTA preferential treatment and is an originating good as set forth in General Note 12 of the HTSUS, the applicable rate of duty is Free.


John Durant, Director
Commercial Rulings Division

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