yes, they came with B&S, around 3hp. they also where equipped with honda engines.

Ok thanks. But mine came with 2 hp 3600rpms

found this

http://forums2.gardenweb.com/discussions/1503987/advice-on-old-trimmer-reel-mower

A little history...

Trimmer originally came with Briggs 3hp engine as the default since inception in the late 1930's. First engine was B&S model 8 cast iron until the late 1950's, then the B"&S 80000 series also 3hp. From the early 1950's the upgrade was the Kohler K91 at 4hp. and later many gardeners fitted 5hp B&S 130000. Honda's, Kawasaki's, and others were also aftermarket options. After the Honda GX160 was introduced in the 1980's it became OEM option, with B&S still the base engine.

The "Original" chain drive 25" was first to go the the larger engines, such as the Kohler, B&S 5hp, and Honda GX160 (5.5hp). The "Original" 20" generally stayed with the Briggs and then used the Honda GX120 (4hp) as the premium engine.

The "Home Owner" 20" (belt off the engine) originally came with B&S 60000 2hp but eventually was upgraded to 80000 series 3hp. Obviously, many people upgrade to Honda GX120 although that is arguably overkill. As with most mowers, the larger engines were more for marketing purposes and competitive response to McLane, Tru-Cut and others. You can witness horsepower inflation in all types of lawn and garden machinery. In fact, many manufacturers no longer mention horsepower (instead torque), as they have been sued for false advertising.

My old man had a Trimmer 25" with B&S cast iron 8 which I remember from the early 1960's. As a school boy it was my job on Saturdays to mow. The engine had more than enough power to handle things. Although I now live in Jersey, I brought an old 20" "Original" with me for nostalgia sake. It is fitted with a B&S "N" cast iron at 2hp. Has more than enough to cut St Augustine, unless you let it get too long and wet.