Runs better when choke is half on

[SARG]

This time it's an Husqvarna trimmer that runs better with the choke half on ...... but I've noted over the years several other small engines acting the same.

What is that a symptom of ? Carb needs adjustment or what ?

 

[buck12]

I have a cheap Weed Eater string trimmer that does the same thing. I have been using it this way for about five years. I am waiting on it to die so I can buy a nice Stihl trimmer but the cheap green machine refuses to give up the ghost. It is at least 13 years old. Every spring I think this is the year I get a new trimmer but it has made it another year.

 

[blueriver]

Check your fuel lines ... mine where old and worn ... sucking air. Replaced them and she runs out like a theif on Saturday Night.

 

[rekees4300]

What is that a symptom of ? Carb needs adjustment or what ?

Not getting enough gas for whatever reason or the gas it is getting isn't fresh. Try some fresh gas with STA-BIL in it and see if that helps.

 

[Skyco]

99% of the time needing partial choke to run means a jet is clogged or restrcited due to crud.

 

[john4153]

Or the carb diaphram/pump has been ruined by our junk fuel with too much ethanol in it. New rebuild kits are supposed to be less affected by the alcohol. I would still check for air leaks first, as that is easy to do. John

 

[studor]

+1 on the crud in a jet -- I have had that happen on B&S, Yamaha, Subaru, Kohler, and Chinese knock-off engines. One batch of bad gas with crud in it will do it or leaving gas in the carb for a year or so

 

[Egon]

99% of the time needing partial choke to run means a jet is clogged or restrcited due to crud.

+ two on this.

Adjusting the jets may help? May open up the orrfice to let more fuel through or the crud thru.:thumbsup:

 

[ToadHill]

If you need to run with the choke closed part way it means the mixture is too lean and you have to restrict the amount of air in the mixture to get the combustion mix right. In my experience with small engines it generally means the carb is sucking air from some area other than where it should.

You can check this by using a oil can and while the engine is running squirt a bit of oil around the gaskets on the carb. It it is sucking air from those areas the exhaust will turn blue and the engine will pick up speed for a few seconds.

 

[Travelover]

Could also be leaking oil seals on the crankshaft. If you suck in air there, mixture will be too lean.

 

[westbrooklawn]

Run a little seafoam through it... if that doesn't help, I would almost bet the fuel lines have cracks in them. Lousy gas is hard on rubber lines.

 

[SARG]

Took the Husqvarna trimmer apart an hour ago. I found nothing that needed tightening. The machine looks almost new. I added some straight gas to the mixed to thin it down a bit......... along with some seafoam as suggested.

It does indeed run better with the choke half on as described by the wife. And I noted that while at idle ......... and I pull the choke lever ....... it acts almost as a throttle control. The machine revs up ........ I guess I'll need to tear it down again.

 

[mostly_gas]

+3 on junk in carb. take it apart and blow it out and reassemble. check diaphragm for pin holes and fuel lines/primer bulb are ok. Lastly check routing of fuel lines. Improper routing can also cause symptoms described. Don't ask me how I know:ashamed: