You cannot interchange the Vanguard with the opposed twin engines. They are totally different engines. If you currently have a Briggs Opposed twin engine in there our Briggs Conversion kit (Woods5182) will work in there. If you have a vanguard engine and purchase the 356447, you may have to change minor parts from your original engine to make this work the same as your current engine. You will need to use the drive adapter and muffler off of your original engine. You may have to use the oil filter bracket as well and the wiring may be slightly different. If you drive off the flywheel side of the engine and your engine uses a Booster Fan, you can use any of the engines listed but you will have to use your flywheel, shroud, and starter or starter gear from your old engine. You will need to match up your starter to the correct flywheel, eg: aluminum gear on your flywheel to nylon gear on starter or steel gear on starter to steel gear on flywheel. The 356447 series engine is about 1-3/8" wider than the 303447 or 350447 series. 16hp Vanguards have an all cast flywheel with the fan as a part of the flywheel. The 18hp and up Vanguards have a cast flywheel with a plastic fan that bolts to the flywheel.

Additional Info

If you have a Kohler Magnum, see our 718K Listing