Surging with new carb on the motor

Drewsnyder

Forum Newbie
Joined
Jul 1, 2020
Threads
1
Messages
1
I have a 20hp Briggs on my Ariens riding mower.started surging so I replaced the carb with an eBay 15$ carb and the problem got worse. Now you can only run the mower on full throttle. And to get rid of the surge it has to be almost fully chocked. There is a sweet spot and once you find it, it will run. Oh yeah, and when you get the mower on you can’t idle it down. It full throttle or nothin. Everything is hooked up correctly. Idk what to do than maybe just buy another carb? It had a Nikki carb on it oem but the one I bought was just some cheap Chinese junk. Model number on the engine is 331777-2372-g5 also I drained the tank and cleaned tank and lines thoroughly befor the install of the new carb.
 

slomo

Lawn Addict
Joined
Jul 14, 2019
Threads
76
Messages
4,677
Did you adjust the pilot jet? Most carbs have a pilot and a main circuit. Sounds like it runs good on the main only. Your Crinese carb should have a pilot screw.

Okay I got to throw this one out. "Did you try loosening the fuel cap" LOL Oh and the other one, did you replace the spark plug? Okay back to helping guys out mode. I've never seen a bad mower plug. Just typing out loud. Seen a ton of oily and carboned up suckers for sure. Once you clean them they fire on one pull.

slomo
 

slomo

Lawn Addict
Joined
Jul 14, 2019
Threads
76
Messages
4,677
You don't just bolt on a new car-bu-trator. Need to check intake gaskets, possibly tune the pilot screw and idle speeds. Guess you can get lucky with a replacement car-bu-trator that runs ok out of the box. Best to dial it in so you know it's perfect.

slomo
 

Rivets

Lawn Royalty
Joined
Mar 11, 2012
Threads
55
Messages
14,683
If you replaced an OEM carb costing approximately $125 with one off EvilBay, for $15, I’m willing to bet you don’t have the correct carb for your engine.
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
248
Messages
6,432
shows two carbs were used on this engine:
591736 (Superseded to 594601)
Note: (Nikki) Used Before Code Date 15122300

Part# 594601
Note: (Ruixing) Used After Code Date 15122200
also looking at the intake manifold used it appears to plastic so i would check it for any cracks or splits.
 

slomo

Lawn Addict
Joined
Jul 14, 2019
Threads
76
Messages
4,677
As usual the super team chimes in Scrubcadet10 and Rivets). OP possibly has the wrong car-bu-trator installed. (y)

slomo
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
248
Messages
6,432
I should add, you can find your Date Code where you found your model number
 

seattlepioneer

Active Member
Joined
Jun 20, 2020
Threads
10
Messages
93

Watch this video for additional ideas on things to check and methods of checking.
 
Top