21 hp briggs motor probs
#1
Member
Thread Starter
Join Date: Apr 2007
Posts: 6
Upvotes: 0
Received 0 Upvotes
on
0 Posts
21 hp briggs motor probs
I have a 21 hp briggs mower and i have cleaned the carb replaced the gas new plugs new filters new gas line everything i could think of i am pretty skilled with motors cars mowers ect ....... now i am stumped ok heres the problem when the mower is running without the blades engaged it pops like water in the gas or poor fire but thats been eliminated , when under a load mowing no popping just governs up and down i have also checked the shear key to make sure the timing is correct , also the valves are clean and gap is good , i am truly stumped on this one the mower is only about 4 years old with only about 75 hours on it any help would be great thanks,,
#2
You say it's "popping" at a fast idle with no load & the govenor is "hunting" when the blades are engaged & the engine is under load?? It sounds like it's running lean. You said you rebuilt the carb, have you tried to adjust it to fix this condition??
#3
Join Date: Apr 2004
Location: Upstate New York
Posts: 2,903
Upvotes: 0
Received 2 Upvotes
on
2 Posts
I agree with hopkinsr2 inthat it will be a carburetor issue. But this engine likely has no adjustments, other than idle speed. What you need to have a close look at is the main jet and i'll bet that there is a minor restriction in such. You may well be able to clean it out with torch tip cleaners but if you post back with the model, type and code numbers I can provide you with the part number for a new jet, which would be the best way out as they are relatively inexpensive to purchase.
#5
I agree, the carb needs a cleaning at the least. I've had the same problem on those engines and a good cleaning does the trick.