Bike is running on choke only. Engine dies at normal throttle without choke. Service has been done, oil changed. Even after reducing the throttle, engine rpm does not go down. Engine dies at slow rpm, at idle run etc. What could be the problem........??????? @

if it runs only in choke it sounds like its lean (choke reduces airflow and gets back to a mixture it will run on.....just). It could just be a small bit of crud in the carby jet. You cleaned the fuel system.....did you install or replace a fuel filter? sometimes cleaning the tank and lines stirs up stuff that needs to be filtered.....even though you may had cleaned and rinsed out a lot.

I think you are mixed up. The choke is usually closed to start a cold engine and opened once the motor warms up. The choke is closed to restrict the air flow and make the mixture richer in fuel. You can't open a choke that's already open. It's stalling because it's starved of fuel. Either a blockage or the fuel pump is not supplying enough gas.

Do yourself a favor... take it to a QUALIFIED Professional and get the carb cleaned and set..,

,,. this should fix your scooter...!!

This is probably a blocked idle jet in the carb, caused by standing and fuel gumming the jets up. The jet that the choke uses will allow it to run, but go to normal running and the idle jet is failing. You MIGHT get away with emptying the tank and getting some (expensive) fuel antifreeze (This is ethol alchohol they use in race cars) run through the bike. It might just melt the gumk and clean things out. If it doesn't, then its probably carb off and strip time :-(

Sounds like the idle circuit in the carb is restricted. The engine is running on the choke only. When the engine reaches a certain temp the fuelthat does get is more readily burned allowing you to back off the choke. The choke probsbly can't be completely opened? right? Fuel quality is also something to consider Oil content in fuel affects combustion temps and volatility. _good luck_Ned_

If still under warranty have it serviced (authorized dealer not Joe's lawn mower). There should not be a fee (paid by Husqvarna). There have been carburetor problems. If you adjust it your warranty will likely be void; Joe's small engine service just as likely to void any warranty. Are you using a fresh 40:1 fuel oil mix. The will not start with choke set is normal. Start procedure in your OM says listen for sputter and disengage choke. Almost all new saws have similar start procedure.
Start Procedure
Cold:

1. Ignition on/off to on.
2. Set compression release – optional step even if saw is equipped with a compression release.
3. Pull (close) choke, set fast idle (done when choke closed on some saws); pull starter and listen for an attempt to start. once heard (usually two pulls; no more than 4).
4. Set compression release – optional step even if saw is equipped with a compression release.
5. Push (open) choke pull starter until it starts. (usually first pull).

Warm:

1. Ignition on/off to on.
2. Set compression release – optional step even if saw is equipped with a compression release.
3. Pull (close) choke, set fast idle (done when choke closed on some saws) – Do not pull with choke closed.
4. Push (open) choke, pull starter until it starts. (usually first pull).

If you have more questions or need additional help please reply below and I will get back to you. HTH & Good Luck.
Lou
Thank You for using FixYa.

There are two possible solutions:

1. If you are sure the engine is OK then you can increase the throttle screw to increase idle race. The throttle screw can be found where the throttle wire connects with the carburetor.


2. If the bike is old or if you have not changed the engine oil on time then the bike needs piston ring replacement. This should be done as soon as possible to avoid more engine damage and effect savings on cash.

Try a fuel additive to clean the system, also if the airfilter is dirty or damp, this can cause problems.
You may even have a rust problem in the barrels.
Or even the engine oil may have thickened causing a resistance in the crank bearings, so flush the engines oil ways if other solutions don't work.

hmmm, a few posibilities, might well be split cab diaphragms but overhaul should have spotted that. sounds like either too much gas or not enough, either flooding/gassing up or fuel starvation. could try running it without the aire filter too see what happens. it should run weak so if bike is better then you have too much gas, if bike worse then runnig weak to start with. I have seen this before with one particular cause.... petrol tap was leaking, gas runs past pistons when bike not running, soaks past and into crankcases. as breather recycles vapour back in to air box, when bike warm it's as rich sas hell. take of oil filler cap on engine and have a good sniff. you should smell only oil, if it's a strong smell of petrol, change oil and filter, dump petrol tap or see if new seals available.

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