Small Engines (Lawn Mowers, etc.): b/s 18.5 engine, jet nozzle, sectional index

Question
I bought a cub cadet at a auction at the cub cadet dealer. They put a new head, fuel pump, and carb. The problem is when you engage the pto the vales rattle and it shoot a puff of black smoke, then it run grate. Can you help me with this. 18.5 B/S engine ELS 500 OHV mod. 31q777 type 0305c1 code 040421zd. Cell  

Answer
Hello Dennis:

I Suggest you First Check the Valve Clearances. If these are Not Set Correctly you will have the Problem you Described. Usually if the Valve Clearances are Correct the Problem is then Caused by; 1- the Air Mixture Screws Not bring Set Correctly. 2- the Main Jet/Nozzle being too Large and Requires a Small Main Jet/Nozzle (Walbro Carburetors) or the Main Jet/Nozzle is Worn Out (Nikki Carburetors) and a New Carburetor is Required. You can View a Breakdown/IPL of this Engine at this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select the Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM and Enter the Model (5 or 6 Digits) and Type Numbers (first 4 digits Only). Example: 31Q777-0305. Then Double Click on the Model in the Results Area. Select Sectional Index. Now you can Select the Section of the Engine you Wish to View. 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. Have a Happy Holiday Season and May the All Mighty Bless You and Yours. Be Safe and Happy. 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. Comments and Ratings are Greatly Appreciated. Thanks.

Respectfully

John