How to Install a briggs and stratton 15 hp motor on a white outdoor riding lawnmower

Basically you need to find a model with the same bolt pattern and output shaft length and diameter. Go to a small engine shop to see if they can help you

Hi,
I would recommend a site such as Small Engine Suppliers
Small Engine Suppliers - Your online source for Replacement Small Engines, Tools & Parts (http://www.smallenginesuppliers.com/)
Since they have the crankshaft and engine specs published on their site. Most cranks will be a standard size and sumps generally have two holes at each of the four corners. The trick is actally in the charging system, muffler and fuel system. If not replacing the engine exactly, you may want one with a muffler. If your fuel tank is at the rear of the machine, you will require a fuel pump model. The charging system is a bit trickier so I will add the alternator id doc.
Peace,
Clarke