won't start, won't fire

Narko

Member
Joined
Jul 28, 2019
Threads
2
Messages
11
Have a B and S 143 424152 on a Sears push mower. Won't start won't fire. Sometimes kicks back sometimes as tho it is firing prematurely (well before TDC) . Any ideas?
 

Rivets

Lawn Royalty
Joined
Mar 11, 2012
Threads
57
Messages
14,926
Sheared flywheel key would most likely be the cause.
 

Tinkerer200

Well-Known Member
Joined
Mar 14, 2015
Threads
4
Messages
913
Sheared flywheel key would most likely be the cause.

Yeah and it doesn't take much on push mower. BIL scoffed at me when I showed him a barley marked key telling him that was his problem. Jaw dropped when I installed new key and it started right up. (And I grinned with satisfaction)

Walt Conner
 

Romore

Well-Known Member
Joined
Jan 19, 2019
Threads
1
Messages
260
The model number indicates a Tecumseh, not a Briggs. Check the hub and blade as well, if not tight the same thing will occur.
 

Narko

Member
Joined
Jul 28, 2019
Threads
2
Messages
11
Yes, it WAS a sheared flywheel key. Thanks Folks. Went to my diecast bucket and found a used one which in put in with the help of a neighbor. Will start and run now just don't have the linkage hooked up right so isn't running as should. Can any one post a pic. In meantime i'll see what I can find on YouTube.

Was not able to find something that specific on YouTube.

Seem to have throttle and governor linkage hooked up properly now and all parts back on. Torqued flywheel nut to 40 ft lb. Does this sound right? It had loosened up after first successful start up. Tomorrow gas in tank and cut-grass test.
 
Last edited:
Top