Sunnen Products Company

Table of Contents

Introduction

The Sunnen Products Company was founded in St. Louis in the early 1920s as a maker of valve spring lifters and later became well known for its cylinder honing tools.

Company History

The Sunnen Products Company was founded around 1921 by Joseph Sunnen as the maker of a screw-adjusted valve spring lifter. The company initially operated in St. Louis, Missouri.

Fig. 1. 1921 Ad for Sunnen Screw-Adjusted Valve Lifter. [External Link]

By early in 1921 Sunnen Products was offering its first product, a screw-adjusted valve lifter.

Fig. 1 shows an ad for the Sunnen valve lifter, as published on page 116 of the March 3, 1921 issue of Motor Age.

The text notes that the product was distributed by the Banner Accessory Manufacturing Company.

Fig. 2. 1921 Notice for Sunnen Screw-Adjusted Valve Lifter.

The composite scan in Fig. 2 shows an early notice for the Sunnen valve lifter, as published on page 45 [External Link] of the March 17, 1921 issue of Motor Age. (The text has been re-flowed into a compact block.)

The text notes the company address as 2717 Lafayette Avenue in St. Louis.

The illustration shows the valve lifter with an adjusting screw. This lifter is described by patent 1,452,714, filed by J. Sunnen in August of 1921 and issued in 1923.

The Universal Valve Lifter

Fig. 3. 1925 Notice for Sunnen Valve Lifter. [External Link]

Within a few years Sunnen had developed a new design for an adjustable valve lifter, which was described by patent 1,588,504, filed by Joseph Sunnen in 1924 and issued in 1926.

Fig. 3 shows a notice for the Sunnen adjustable valve lifter, as published on page 30 of the January 8, 1925 issue of Motor Age.

The text notes the company address as 620 Tower Grove Avenue in St. Louis.

Cylinder Honing Tools

Fig. 4. 1928 Notice for Sunnen Cylinder Hone. [External Link]

By 1928 Sunnen was offering a cylinder honing device.

Fig. 4 shows a notice for the Sunnen cylinder honing tool, as published on page 60 of the October, 1928 edition of Motor Record.

Cylinder honing tools went on to become a major product line for the company.

Patents

Trademarks

References and Resources

Photographs and observations of particular tools are based on items in the Alloy Artifacts Collection.

Catalog Resources

Selected Tools

We have an example of a Sunnen valve lifter and are preparing it for display.

Sunnen [EL-100] Valve Lifter

Fig. 2. Sunnen [EL-100] Valve Lifter, with Insets for Top View and Marking Detail, ca. Mid to Late 1930s.

Fig. 2 shows a Sunnen [EL-100] valve lifter, stamped with "SUNNEN" in large letters on the front, with "Sunnen Products Co." and "St. Louis, MO." plus "Made in U.S.A." on the back.

The back is also marked with a "Pat. Pend." notation, but the corresponding patent has not been located yet.

Our example is not marked with a model number, but the catalog lists this as model EL-100.

The 1957 catalog notes that this model had been a leading product "For Over 20 Years", suggesting that it was introduced in the mid to late 1930s. The patent pending status on our example suggests early production.

Sunnen [PN-50] Torque Wrench

Fig. 3. Sunnen [PN-50] Torque Wrench, with Insets for Side View and and Marking Detail, ca. Late 1930s to 1940.

Fig. 3 shows a Sunnen [PN-50] torque wrench of unusual design, stamped with "Sunnen Products Co." and "St. Louis, MO." on the side flange, with "Pat. Pend" and "Made in U.S.A." below.

The handle body is marked with graduations in inch-pounds from 200 to 1200, as seen in the right middle inset.

The overall length is 19.5 inches as photographed, but will vary somewhat with the torque setting.

The pending notation refers to patent 2,205,501, issued to J. Sunnen in 1940.

Our example is not marked with a model number, but the 1957 catalog lists this as a PN-50 "Automatic Torque Wrench".