Browse Publications Technical Papers 2000-01-2015
2000-06-19

Valve Seat Recession - An Independent Review of Existing Data 2000-01-2015

The mechanism of valve seat recession is well understood and a review of the existing literature shows that it consists of two processes - the generation of hard particles that then grind or abrade the valve seats. Metallic fuel additives can prevent recession by stopping the generation of these hard particles. Both new and previously published data are presented to demonstrate that low concentrations of all the commonly available additives provide adequate protection for most service applications. However, the data also show that severe testing with low treat rates will produce valve seat recession. The author argues that, if sufficient concentration of additive is used, the initiation of recession is stopped under extremely severe conditions and alternatives to lead can offer complete protection.
The paper concludes that the use of lead replacement additives should be at the maximum possible level commensurate with all aspects of engine performance. There are no standard tests for valve seat recession and, as a consequence, the additive supplier must be responsible for recommending dose rates that do not lead to potentially harmful side effects.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
JOURNAL ARTICLE

Review: Fuel Volatility Standards and Spark-Ignition Vehicle Driveability

2016-01-9072

View Details

JOURNAL ARTICLE

Ignition of Combustible Materials by Motor Vehicle Exhaust Systems - A Critical Review

2010-01-0130

View Details

TECHNICAL PAPER

On the Time Delay in Continuous In-Cylinder Sampling From IC Engines

890579

View Details

X