Rotax 582 fuel problem

[dalords]

Anyone out there a Rotax genius.? I am at a loss. The engine runs rich. I have the right jetting I just replaced both choke plungers, set the choke adjustment all the way in to make sure the chokes are seating. Float level set so fuel is 1/2" from top if bowl. Vent holes are in the crossover tube that vents the bowl. Everything appears right but still runs rich. After running if you pull the carbs off fuel comes pouring out of the intake boots both of them. From full power when you pull back to idle it will idle at about 2500rpm and slowly bleed off to 2000 rpm which is where I have it set. I assume it does that because the intake boots are so full. Any help would be great

[SS7Flyer]

How old are your carbs? The float system is mechanical and parts in there do wear out which could cause the floats to stick. That will usually show itself by fuel coming out of the vents though. Are you using an electric fuel pump? Do you have a plunger primer set up in addition to your choke? Are you running ethanol fuel? Did this just start after it had been working good? Have you made any changes recently i.e. jetting? I think the first thing I would do is sit down with both your carbs on a towel on your work bench and tear them completely apart and look for any plugged jets/orifices and worn parts on the float system. Sometimes a teeny tiny piece of crud in a Bing carb can really mess with stuff. I had a partially plugged idler jet one time that I chased for a few weeks befor I finally found it. Hopefully it's something simple.

[Dave F]

When you say that you pull the carbs after running
where does the fuel come from?

Doess it leak just sitting there?

[dalords]

The primer lines have disconnected and capped. The carbs I would assume are fairly old, original to the plane which was built in 1993. This is a rebuilt project that I am working on so I have never seen this plane in action. No electeic pump, standard pluse pump. After running for say around 10 minutes on the ground and warmed up if I pull the carbs off fuel literally runs back out of both black intake boots. Even during the entire engine run the smoke never clears up. Pushes a fair amount of blue smoke even warm. Spark plugs always really wet looking.

[Dave F]

the 582 run smooth at 3000 rpm plus?

how is the idle? smooth or not?

blue smoth is the oil ......

is the injection set properly or are you using pre mix?

if the needle and seats are working properly then no fuel should leak out.

[dalords]

runs smooth, oil injection set correctly so at 3000 rpm line on the level aligns with line on the housing. Needle and seat appear to be working correctly. This one really has me baffled. like I said all things are set up correctly. its just a mystery to me

[JRLAMB]

i was running to lean.... pulled carbs... set c clip to number `4 slot (bottom)..... ran great....

so try c clip in no. 1, top slot of needle , might do it.... rick lamb

[Av8r_Sed]

What prop are you running? I have an IVO medium 2 blade which made for high vibration near idle due to it's high moment of inertia. The vibration caused serious carb problems with fuel spilling from the overflow. I had to put in a clutch to resolve that.

Also, you might want to replace the viton tipped float needles. If you have the originals, the viton may have hardened preventing them from sealing properly.

[dalords]

Thanks for all the help

[JRLAMB]

What prop are you running? Also, you might want to replace the viton tipped float needles. If you have the originals, the viton may have hardened preventing them from sealing properly.

good point.... my engine set up is something like the "03 edition... bought the project in florida 2 years ago... finishedand am not at 10 hours...

i am running a gsc 68" 3 blade...
just had the 3-1 changed to 2.62 at lockwood... we couldn't get the power to the prop...

taxi test yesterday... seemed to indicate we are on target...

if you are ever in perry county, pa..... near harrisburg, pa.... fly by... there is 1400 feet in front of the house...

rick

[Av8r_Sed]

The GSC moment of inertia probably isn't too high. If you suspect vibration is causing the float needles to unseat resulting in rich running near idle then check that you've got the blade pitch set properly.

Other threads here deal with GSC setup. Just be careful not to overtorque the hubs. Also, a general caution not to try high speed taxi testing in a Kitfox. You'll be on your way to your first ground loop in nothing flat.

[Av8r3400]

Also, a general caution not to try high speed taxi testing in a Kitfox. You'll be on your way to your first ground loop in nothing flat.

+1 on that advise, Paul.

[Dave F]

I have seen this before and it was from debris in the fuel line that got lodged in the needle and seat.
blew out the line and carb - problem gone.

[kmach]

I agree with previous posts, and think it could be .

If the prop pitch is set too coarse ( too low of a static rpm) it can make it run like crap.

If the seat and needle in the carb are not totally shutting off fuel you will have excess fuel at lower rpms. or possibly a drip/ leak when it is sitting not running .

[dalords]

I dont have the prop installed so I can rule out any vibe problem. Since putting thr motor on we have ran it about 2 hours total time. I have noticed a decrease in the rotary valve oil tank. Normal or not?

[Av8r_Sed]

OK, you can't tell much about a 2 stroke operation without the prop load on it.

If it were me, assuming a used engine of unkown history, I'd first pull the exhaust header and inspect the rings and piston skirts. I'd also pull the plugs and inspect the tops of the pistons for melting or excessive carbon. You probably will need to replace the exhaust gaskets when reinstalling the header.

If that's all good then install the prop and get it pitched about right before you test it further. Then restore the factory jet settings, set the idle and see how it's doing.

Normally it won't consume oil from the rotary valve resevoir.

[akflyer]

running without the prop is not a good idea.. put the prop on and warm it up with old plugsd, then do a quick plug swap, fire it up and run it at full power for a minute or two, shut it down (dont let it idle for more than a couple seconds), and then take a look at the plugs. are then a nice tan? Black? white?

If the RV oil level has gone down a little, it could be that the system was not fully bled. I would fill it to the line and see if it drops again or if it hold now.

running rough at idle could be the carbs are not set right (air bleed) or not synchronized, or the needle seat is not holding.

The factory jetting chart should get you very close.

There have been alot of folks who had a rough running engine with the GSC prop that smoothed right out with the installation of an IVO or other prop. 3 blades will run smoother than 2 blades.

I think the marks on the oil pump lever are spose to line up at idle...