Briggs Vangard 16hp #303777 HELP!!!

[tec2484 1]

I have a Vangard 16hp #303777 type 0122 that when your mowing and have the throttle over half way the governor kicks in and it starts blowing black smoke out the muffler and starts chugging down until you pull the throttle back and let it catch up. I have tried adjusting the governor 3 or 4 different ways and still the same thing. I can't find how it should be adjusted, (I tried like I did on my 728 witch worked great) but this engine didn't change. Any ideas??? George

[Doll 0]

this sounds more like gas or oil dumping into the engine than a governer problem to me. If something does happen to cause the engine to lose rpm, the gov will open up. Look at the oil level and make sure your not over full first of all. If you are, see if the oil smells of gasoline. If there is fuel in the oil, check the float in the carb and the fuel pump etc.. Being over full will cause the engine to push crankcase oil into the intake.

[tec2484 1]

The oil level is right on. It acts like when the governor kicks in, it makes a real rich mix. Just had an odd thought, I wonder if it is possible for the governor to cause the choke to close? (I said odd). I will look at that tomorrow. with out a load on the engine (sitting still or driving it around the yard) it runs great. Nice and smooth at all engine speeds, And will respond to the throttle great with no hesitation.

[UCD 14]

Air leak, bad carb/intake manifold gaskets, worn throttle shaft.

[ambler 0]

breather.

[Al 6]

Hi, Does it do it with the air cleaner removed?? Is the air cleaner soaked with oil?? Is there oil visible in the crankcase breathe tube? Is the base of the air cleaner oily? Al Edem

[KenK 0]

Is there a lot of hours on the motor?Kind a sounds like a head gasket problem.

[tec2484 1]

It does it with and with out air cleaner. The air cleaner shows no oil in filter or laying in bottom of housing. The breather tube looks clean. The engine has a lot of hours but doesn't burn oil or throw any blue smoke. Tonight I will try spraying carb cleaner around the gaskets and throttle shaft and listen for any changes. George

[tec2484 1]

I tried the carb cleaner and no change at any rpm, Low, mid or high.

[andrewk 0]

I do a compression and leak down test to see where things stand mechanically, then I would probably look at fuel delivery... If the air cleaner makes no difference, it could still be in the carb, but you should do some diagnostic tests to ensure you are heading in the right direction. JMHO Andrew