G'day folks,
As you're probably aware, the Model Number breaks down into info on the basics of the engine: capacity, design series, crankshaft orientation, carby type, PTO bearing type/auxiliary PTO's or reduction drive fitted/lube system, and starter type.

The Type Number - from one of the Briggs Service Manuals:
Quote
The type number identifies the engine's mechanical parts, color of paint, decals, Governed Speed, and Original Equipment Manufacturer.

As far as I can find out, Briggs have never released a key to interpreting Type Numbers on their own. It's very much an 'internal code', known only to them.

It's also possible that the exact meaning of a Type Number is model-number dependent too; i.e. a given Type Number may denote different things on differing models.

But as SuperDooper says, it is essential for determining part design changeovers, in many cases.

Cheers,
Gadge

"ODK Mods can explain it to you, but they can't understand it for you..."

"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."