B&S governor hunting on idle.

[dually]

I recently bought a MAX II I detailed the machine well and service the engine B&S 16HP Vanguard and transmission T2 ATF hyd. I took it to the water and performance was excellent but the engine hunts at idle. I have not service the carb and plan to do soon replaced the fuel pump. Is there anything eals that could cause this problem?

[TalSet]

just exactly do you mean when you say she "hunts"?

[LarryW]

If it hunts it must have an adjustment or gunk in the idle circuit. It starts to die, governer open throttle and it takes off again. Goes into idle where it cant run right and cycles. Assuming you have gunk in it, you could run it without the air cleaner and rev it up buy hand with max in neutral. Rev it high and cover the carb. which would choke it out. Hold it wide open and let it almost die and then uncover it but make sure you hold the carb wide open. It will cough and spitter and finally clean out. If you held it to long and it dies hold it wide open when cranking it over until it fires up. This creates a vacuum that can clear stuff out sometimes. It also could just be an adjustment. If you mess with adjustments turn them slightly and remember how much you turned them so you can return them if needed. If that dont work and you are sure you fuel line isn't clogged or fuel filter then you probably have something jammed in the jets and ports in carb. You can use a wire from a wire brush to clean the real tiny holes if there is something real stubborn in them. Good luck!

[Robinhood02]

hunting is when the engine revs up and down at idle, the only thing i have found to cure is leave the choke on just enouph to make it stop

[liflod]

You need to adjust the idle exaclty as the manual tells you to adjust it. I believe I posted the procedure on this site years ago.
If you adjust the idel speed with the screw, it will hunt. The manual says to adjust the idle by bending the tab with the idle spring attached.

[JAM]

dually
I just bought a 94 max II with a 16 hp b&s, I got mine and it surged and would never settle down, the choke trick works but I did not think the choke needed to be used to properly adjust the idle, so Idrained the fuel cleaned the tank,lines,fuel pump, and carb. not as much work as it sounds. You should have seen the gunk in the fuel mixture screw and bowl, now the engine runs smooth. I also put new plugs, oil (5w-30 synthetic) seemed to help. B&S website says that carb problems and bad fuel are the biggest culprit to running ruff, hard starting, not idling at all, and needing the choke to run. I am new to the 6x6 world and with help from the internet and the good folks here at 6x6 world have been able to get mine running strong.
Good luck,
jam

[plott hound]

yupper,hunting and surging is always caused by crap in the carb

[dually]

Talset, Thanks but, hunting governor is when the gov. with the engine running moves back and fort instead of stabilizing.

Thanks am waiting for my carb kit to start work on the carb.

Jam, thanks for the response. I did all of the above with exception of the carb. rebuilt. Watch out for the fuel line (rubber) make sure it is a fuel host I found mind to be a regular rubber host not for gasoline. If so change it because it deteriorate inside. Thanks again.

Will do liflod. and thanks for the info.

Thanks Larry, I am going to rebuilt the carb and set the idle as per manual (B&S). Damn good engine very fast.

Thanks Robinhoodooo2 but my chock cable is rusted together and will replace that too. However, I hoping by that time I will have the hunting stop with carb cleaned.

[JohnF]

This can happen if you are misjetted. Did the previous owner live or use the machine at a different elevation?

[jimsummit]

The 16hp has small stopper on the fuel adjustment screw on the side of the carb. Cut the plastic stopper so you can adjust the screw till it gets the right amount of fuel. It will idle much better. I don't know why briggs leans them out like that.

[racerone3]

They are set so lean from the factory so as to meet emissions regulations set by the EPA. This is also the reason for the plastic limiter cap on the adjusters. a lot of the newer carbs on mowers have at most an idle screw that can be adjusted.