Conquest flooding out at idle.

[thorn]

My conquest runs/starts great for me with one exception. When I drive it for a while (say a few miles) and then stop and let it idle, it will idle fine for about a minute and then it will flood out and die. I can then smell gas fumes (not a dangerous amount). It will start back up but only if I give it full throttle. It will blow some black smoke out a bit because it is flooded, but runs great under power. It seems to only do it at higher altitudes and after it has been worked some.
If I start it in my driveway at lower elevation and cold, it will idle fine.
I am wondering if my float needs to be adjusted a bit lower? I did remember adjusting it a bit higher when I was troubleshooting it for a stuck solenoid when I first got it.

Am I barking up the right tree here? I am not really worried about it not starting, but it is some times again in the a$$ if I need it to idle for me w/o giving it some throttle to burn off the excess. Any thoughts?

[msafi65]

Sounds like float valve is leaking by a little. Pull the needle and if it has a viton tip just turn the tip and clean with your fingernail. Sometimes you feel a small piece of trash Imbeded in the surface usually not. Just make it dull finished again and set to recommend level. If you have the carb off and have any way to test it it should hold pressure upside down to over 5 psi. I have an old squeeze bulb from blood pressure cuff with a 15 psi guage on it. I flip carbs over and pressure test the needle. You would be surprised how many with screw in seats that leak by the gasket. Does your Argo have the stock pump or a low pressure replacement? Good luck.

[JohnF]

Could be that the float valve is leaking and dumping fuel like msafi65 said. This shouldn't be elevation dependent.
It could also be that you need to adjust your low idle mixture. These engines run rich at low idle anyway. Something along this line will be density altitude dependent. Kinda like needing to go down in main jet size.

[thorn]

Sounds like float valve is leaking by a little. Pull the needle and if it has a viton tip just turn the tip and clean with your fingernail. Sometimes you feel a small piece of trash Imbeded in the surface usually not. Just make it dull finished again and set to recommend level. If you have the carb off and have any way to test it it should hold pressure upside down to over 5 psi. I have an old squeeze bulb from blood pressure cuff with a 15 psi guage on it. I flip carbs over and pressure test the needle. You would be surprised how many with screw in seats that leak by the gasket. Does your Argo have the stock pump or a low pressure replacement? Good luck.

I put a new OME pump in it about 90 hrs ago. Thanks for the input.

[thorn]

Could be that the float valve is leaking and dumping fuel like msafi65 said. This shouldn't be elevation dependent.
It could also be that you need to adjust your low idle mixture. These engines run rich at low idle anyway. Something along this line will be density altitude dependent. Kinda like needing to go down in main jet size.

I have messed with the low idle mixture adjustment a bit by trying to set it in between the raising/lowering on rpms. Maybe It needs to be on the lower end. I did re build the carb as well when I bought it with a fresh needle, but I know it could just take a piece of "crud" causing a problem for it.

[plott hound]

hey thorn,when I rebuilt my conquest I had major carb troubles.had that sucker apart 3-4 times and each time I found more crud,could not get get it all out.finally I bought a new and was done with it.

[thorn]

I rebuilt the carb when I got it as well (new float needle, gasket, etc..) never had any issues other than this. It seems like if I had a leak in the float needle it would act up all the time at any altitude because a leak is a leak. I have had it idling in my driveway (5300 feet) for 20+ minutes and it purrs like a kitten. It only happens at altitude (8,000-10,000 feet) so I think I need to play with the low speed idle adjustment and maybe starve it a little. Besides that it runs excellent.

[msafi65]

I'm thinking all is well with float valve now. Try adjusting idle mix when at altitude and try to find a happy medium. Always had to rejet the snowmobiles to run in the mountains without foweling plugs. Where in Utah are you? We spend some winter months in St. George area.

[plott hound]

I rebuilt the carb when I got it as well (new float needle, gasket, etc..) never had any issues other than this. It seems like if I had a leak in the float needle it would act up all the time at any altitude because a leak is a leak. I have had it idling in my driveway (5300 feet) for 20+ minutes and it purrs like a kitten. It only happens at altitude (8,000-10,000 feet) so I think I need to play with the low speed idle adjustment and maybe starve it a little. Besides that it runs excellent.

ahhhhh crap,forgot about that altitude thing.

[thorn]

I'm thinking all is well with float valve now. Try adjusting idle mix when at altitude and try to find a happy medium. Always had to rejet the snowmobiles to run in the mountains without foweling plugs. Where in Utah are you? We spend some winter months in St. George area.

I am about a 5 hour drive north in Bountiful.

[tshea]

I had the same issues - rebuilt the carb at least 3 times - never could solve the new issue - New carb was the best investment I ever made - especially 40 miles from nowhere.