Briggs & Stratton won't run under load

[ShafferNY]

Hi everyone,
I have a 5hp(maybe 3 1/2) B&S on a Homelite water pump. It's a horizontal shaft motor with a tank mounted carb.

I can get the motor to run, but it won't run under load. As soon as you put it under load, it will die off within a few seconds.

I lost the original governor spring, so I had to replace it. I got a new one at Napa. The governor moves freely, so I don't think that's a problem. I've tried cleaning out the carb several times, and it still does the same thing. I did a compression test and it barely reached 50psi, so I thought it was the rings. I replaced the rings and now it has good compression, but it still does the same thing.


I've tried everything I can think of. What's left?

[Restrorob]

Hi everyone,
I have a 5hp(maybe 3 1/2) B&S on a Homelite water pump. It's a horizontal shaft motor with a tank mounted carb.

I can get the motor to run, but it won't run under load. As soon as you put it under load, it will die off within a few seconds.

I lost the original governor spring, so I had to replace it. I got a new one at Napa. The governor moves freely, so I don't think that's a problem. I've tried cleaning out the carb several times, and it still does the same thing. I did a compression test and it barely reached 50psi, so I thought it was the rings. I replaced the rings and now it has good compression, but it still does the same thing.


I've tried everything I can think of. What's left?

Its possible you sucked a stick or rock through the pump and partly sheard the flywheel key and I would Recommend going to your Briggs dealer and getting the proper Gov. spring for your model,Type and code engine.
There are many different springs per application,without the proper spring the engine could not run as intended.

[ShafferNY]

I've had the pump section completely apart and everything is good. The only thing I can figures is that the gov. spring is the wrong one.

How many turns should the adjustment screw on the carb. be backed out to start with? I believe general rule of thumb is 1 1/4 to 1 1/2. Are these engines the same?

[Restrorob]

I've had the pump section completely apart and everything is good. The only thing I can figures is that the gov. spring is the wrong one.

How many turns should the adjustment screw on the carb. be backed out to start with? I believe general rule of thumb is 1 1/4 to 1 1/2. Are these engines the same?

On this engine 1 turn to start then adjust as required 1 1/2 is way too rich.
when you install the proper gov. spring put some water in the pump and set throttle wide open and adjust gov. to 3600 R.P.M.