Fans

Procedures for utilization of Auxiliary Engine Cooling

California Exhaust Emission Standards and Test Procedures for 2005 and Later small off-road engines discuss the conditions for the usage ofauxiliary engine cooling during the certification and production line testing. Based on the test procedures, the use of auxiliary engine cooling must be indicated in the certification application, andthe manufacturer must justify the need for such cooling strategies to the satisfaction of the Executive Officer.

This document is intended to provide further guidance to the manufacturers withregards to the use of auxiliary engine cooling systems/fans.

Manufacturers must provide answers to the following questions for each engine family:

a) During certification testing, was anycooling strategy/fan employed? Yes No

b) If Yes to (a), was the intent to simulate real world, in-use operation/effects? Yes No

c) During certification testing, were any test procedures,strategies or equipment employed that may have the unintended effect of cooling the engine, including, but not limited to circulating fans to maintain test cell temperature, or air-conditioning ventsdirected towards the engine? Yes No

If yes to any of the above questions, please provide information demonstrating that such cooling is representative of in-use operation. Such informationmust include, but not be limited to, specifications of fans/blowers/air conditioning used in the test cell (size, flow, etc.), diagrams indicating the layout of the test cell and the layout offan/blower/air conditioning, air flow direction relative to the engine, and inlet air temperature impacts with and without the cooling strategy.

Generally, the Air Resources Board (ARB) considers theuse of auxiliary engine cooling during certification (including service accumulation) and production line testing to be inappropriate. Manufacturers are only allowed to use auxiliary engine cooling...