Max ii 14hp fouling plugs and stalling

[Mythane55]

Hi there. Just picked up a 95 max in great condition. Only problem I have is the motor stalling out after I hit a few good bumps. I pull the choke out quickly and it corrects itself and starts running again ( lack of fuel I'm guessing) but then the plugs are getting very sooty like its rich... It don't smoke at all and the carb has been cleaned a few times by me (looks like a new carb) fuel delivery is clear. Float is adjusted properly. Any ideas? Are the 14hp v twin brigs notorious for this ?

[Rusty-Gunn]

I have no idea about the.engine, but welcome to the best 6x6 site on the net. I'm sure you'll
find it to your liking. Plenty of good people with the answers you seek.

[Adondo]

I'm new here too. I've been a motor-head forever, with endless race Jeeps etc., including a couple of scratch-built turbo systems.

In off-roading, when fouling happens, it's usually because the float's set too high. It might be set to specs, but those specs are for a lawnmower traveling on flat grass. (Small engines are designed for such apps rather than a "dynamic" environment like in a 6x6) The float (and the reservoir it supplies) is only there for acceleration. If you're on/off the throttle constantly, it needs a supply for squirting into the manifold to prevent stumbling. (Feeds the accel pump) When running mostly steady state, like a Race Jeep through deep mud, the float can be set much lower. That helps prevent gas from sloshing over the overflow vent and into the engine. The same principles should apply here too. When running flat out, the float/reservoir has very little function.

The ultimate off-road carb is the SU side draft, which you used to see on race Jeeps, Baja 500 trucks, rally cars etc. They don't have the overflowing bowl full of gas problems. Now, of course, most rigs are fuel injection so it's moot.

Lack of fuel supply will cause lean-out and lack of power during high throttle positions. The plugs will be overheated and whitish looking instead of carbon covered. Fowling with bumps is because gas spills over, and that's what carbons up the plugs, (mixture goes super rich) which doesn't always burn away very fast. You might also clear it by going WOT for a few seconds instead of choking it. Also, if setting the float lower fixes it, replace the plugs. They're compromised now.

[Mythane55]

I thought the same thing so adjusted the float about 25% lower... I still need to pick up some new plugs for a decent test. Thank you.