QuestionBriggs & Stratton Model 407777 Type 0128E1 Code 000607YG.
Let me start out by saying thanks in advance for any information you can give. I certainly appreciate it.
This motor is on a Troybilt riding mower. I was mowing along and all of a sudden, the motor rpm's became excessive and would not idle down. I had to cut the key off because it was revving so fast I thought it was going to take off like the space shuttle.
I took the front end off the mower to get easy access to the carburetor and linkage. I quickly noticed that the carburetor throttle lever that is supposed to be against the idle speed screw is no where near touching it. As I am sure you know, the other end of this linkage goes down and hooks to a what I would call a arm that is connected to a rod that goes into the motor.
I let the engine cool completely off and restarted the engine. It again just ran at excessive rpm's. I pushed up on the linkage which pushed the carburetor throttle lever against the idle speed screw. Whenever I did this, the engine idled down. As soon as I let go, it sped back up. I have to assume that this part going into the motor has something to do with this. Can you please advise on what you think the problem is and what I need to do to fix it. Thanks again. James
Answer Hello James:
This Problem is Rare But it Does Happen. The Internal Governor has Broken. Go to this Addy http://shop.briggsandstratton.com/BShopProductListingPage.asp?rsvp=0&PARENTID=0&... and Enter the Model Numbers 407777 and the Type Numbers 0128 and Click Search. Then Scroll Down to the 2nd Listing and Click on View PDF. This will Download the Breakdown/IPL for this Engine. On Page 8 of 20, Diagram #219 is the Governor. It Sets on the Cam which is on Page 3 of 20, Diagram #46. This will have to be Replaced. The Engine will have to be Removed from the Mower and the Oil Pan Removed. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks. Be Safe.
Good Luck
Respectfully
John
PS: Happy Thanksgiving and Merry Christmas (:-))
