QuestionQUESTION: I have a Craftsman 917.378772 (Briggs & Stratton 128600) mower which has started very well (cold) for 6 years and has recently become very difficult to start. when it finally runs, it's a bit rough and skips occasionally. I tried all the usual stuff (new spark plug, etc.) and even changed a cracked fuel line...but no luck with the hard starting. Then started to look at the air filter/carburetor because there seems to be a different sound when the primer bulb is pressed. Found a dime-sized piece of metal in the carburetor bowl. From the parts list, it seems to be a welch plug? Could this little disc be the cause of the trouble? Can I fix it without getting an entire carburetor kit? Thanks...Linda
ANSWER: Hello Linda:
Yes the Welch Plug Not Installed Will Cause the Problem you Described. 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 and Type Numbers (128602-0215). Then Double Click on the Model in the Results Area. Now you can Select the Section of the Engine you Wish to View. The Welch Plug should be # 127 (BriggsPart # 694468). Place the New Welch Plug Into it Recess with the HUMP UP. Use a Small Round Punch and Punch the Center of the Hump Down Until the Hump is Slightly Dimpled. This Locks the New Plug Into Place. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. 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 9pm EST (US). My New Day Starts then. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: Mr. Bridgers...I decided to order a 'kit' for the carburetor since it included the welch plug, and since there really wasn't enough clearance to work on the bottom of the carburetor without taking it off the lawnmower. the parts came on Monday at lunchtime and by 5 o'clock I was mowing the lawn again. My lawnmower is probably perkier now than when it was new! Thanks for your encouragement. I'm going to try this carburetor kit procedure on my dad's old snowblower too.
Another quick question: the booklet that comes with my mower says that the spark plug gap is .020", and I've always heard that lawnmower's are around .030". The recommended Champion plug (RC12YC) always is .030 when it comes new out of the box. Do you think the .020 is correct? Maybe it is a misprint? thanks heaps, Linda
AnswerHi Again Linda:
Use the .030in Gap for the Plug. I have Seen Recommended Gaps Up to .045in and have Found the .030in Gap Performs the Best. Thanks for the Update and Good Words. Till Next Time. May All Your Mechanical Problems be SMALL ONES and May the All Mighty Bless You and Yours. Thanks Again.
Best Wishes and Good Luck
Respectfully
John
