Skip to main content

Valve Timing

Society: ASME Main Category: Mechanical, Road Sub Category: Road Transportation Era: 1950-1959 DateCreated: 1957 Jacobs Manufacturing Company Bloomfield State: CT Zip: 06002 Country: USA Website: http://www.asme.org/about-asme/history/landmarks/topics-m-z/road-and-off-road-transportation/-108-jacobs-engine-brake-retarder-%281957%29 Creator: Cummins, Clessie Lyle
The Jake Brake permits large trucks to descend long, steep grades at a controlled speed. It was the first practical mechanism for altering on demand the valve timing on a truck diesel engine, thereby converting the engine to a power absorbing machine. The modified engine can continue to power the truck in normal operation, allowing service brakes to remain cool for emergency situations. Invented by Clessie Lyle Cummins (1886-1968), this device (produced by the Jacobs manufacturing company since 1961) has contributed significantly to highway safety.
YearAdded:
1985
Image Credit: Courtesy Wikipedia/Sierra Fournier (CC BY-SA 3.0) Image Caption: Jacobs Engine Brake Retarder ("Jake Brake") Era_date_from: 1957
Subscribe to Valve Timing
The Jake Brake permits large trucks to descend long, steep grades at a controlled speed. It was the first practical mechanism for altering on demand the valve timing on a truck diesel engine, thereby converting the engine to a power absorbing machine. The modified engine can continue to power the… Read More

We hope you enjoyed this essay.

Please support this 70-year tradition of trusted historical writing and the volunteers that sustain it with a donation to American Heritage.

Donate

Stay informed - subscribe to our newsletter.
The subscriber's email address.