Small Engines (Lawn Mowers, etc.): Snapper mower rear engine replacement question., crankshaft diameter, john snapper

Question
Hello John,  Snapper 30128E with a B&S Model 281707 Type 023201 Code 90082211 needs new engine.  Could you break down the numbering system B&S uses (what each digit in the Model and Type denotes)?  Can't find it on the website and there are many similar models on eBay with different numbers but near identical specs.  For instance,  B&S tech support recommended Model 21B907 Type: 0029 but there's a great price on a Model 21B807 Type 0239-SD.  Detailed engine specs I'm finding hard to come by.  Assuming I buy the right mounting bolt pattern, shaft dia. and length, physical dimensions, and alternator type (I think 3-14 amp will do), is this a pretty easy bolt together job or should I leave it to a pro?  With 3 kids, anything more than 2-3 hrs. really is tough to squeeze in.  Thanks,  Dan

Answer
Hello Dan:

Go to this Site Addy; http://faqs.custhelp.com/cgi-bin/faqs.cfg/php/enduser/std_adp.php?p_faqid=1487 and Select the Replacement Engine Catalog (in Blue Letters). This Catalog has all the Engine Specifications you should Require to Compare the 2 Engines Crankshaft Diameter, Length and ect. The Bolt Pattern is the Same and from Looking at the Breakdowns for Both Engines, I See No Reason for the Engine Not to Drop In and Bolt Up with No Problems. I Did Notice the 21B807-0239 has a Different Crankshaft Part Number, so be Sure to Check the Crankshafts External Specifications Closely when you Compare the 2 Engines in the Catalog. If you Wish, I can Use the Catalog and Check the Engines Specifications More Closely for you. It May Take me 24 to 48 hrs to Respond if I Assist in this Endeavor, but I am Happy to Do so if you Wish. Just Let me know. The Only Problem with Changing the Engines you May have is Removing the Drive Disc or Pulley (depends on the Mower Model) from the Crankshaft. You can View a Breakdown/IPL of the Unit at this Site Addy; http://www.briggsandstratton.com/maint_repair/manual_and_more/doclist.aspx?categ... and Enter the Model Numbers (XXXXXX) and Type Numbers (XXXX) in the Appropriate Boxes and Click GO. Then Select Download PDF. I Used the Breakdowns at this Addy to Compare the Engines. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.

Respectfully

John