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Hello everyone. I have a briggs 4hp Quattro (10A902 2271 E1) that I am trying to repair.

The governor setup had been tampered with and the carb needed a cleaning. I have replaced the governor springs. The carb is now clean and it runs but seems to be a little fast.

It has a lever style throttle control. When the lever is in the "slow" position it runs around 2500-2600rpm and at full throttle it runs around 3330rpm. I thought it should run around 3200rpm at full throttle. (Rpm readings were done with a tiny tach).





Any advice on what rpm readings should be at low and full throttle? How would I go about adjusting the max rpm?

I forgot to mention the throttle is at full throttle in the pic.

The actual running speed is set my the mower company, not Briggs.
3300 is fine for a high idle but 2200 is a tad fast for the low idle.
Usually around the 1500 to 1800 mark.
ME thinks you may have an air leak .
That long induction tube is prone to cracking, warping and the tiny bolt ge over tightened & the threads stripped so it leaks at the gaskets.

Ok, that makes sense. I did notice some gas leaking between the carb and gas tank when I ran it today. Could that cause the high rpm? I tried doubling the gasket in case the tank is warped but it didn't help. I wonder if the diaphram has a wrinkle in it from installation. Thanks for the reply by the way.