2 cycle carb cleaning and best winter storage practice

[Paddy]

I have a Stihl FS 55 R weed trimmer. Great machine for the last 10 years or so. But every 5 years or so, the beast slows down, or gets difficult to start.

The first time it did this, I bought the rebuild kit and cleaned it. No improvement at all. Tore it down again thinking I must have missed some little hole. Still no change. I'll add, I did not take out the Welch plugs. But my experience generally the passages are quite large. Welch plugs just allow drilled passages to turn 90 degrees.

So I just bought the Stihl replacement carb and all was back to normal. A few years latter it was acting up again, but it was a clogged spark arrester. Cleaned and back good as new.

So this year I was determined to "clean these carbs" but again, no luck. I bought the new carb and all is good.

I hate to keep spending time cleaning these carbs if it just never works, maybe best to just buy a carb every 5 years. But There has to be something I'm missing, like there is one spot that is clogged 95% of the time. I have a push mower like that, drop the bowl and clean the jet and all is good foe another year.

So is there anyone out there that knows where the one darn place that 2 cyc carbs clog?

Last thought, my winter storage plan is to just run them dry at the end of the season. Is that better than full with gas treatment?

Imput welcome

 

[jbadkins7o]

I youre not running ethanol free run em dry and store them. I run the VP SEF Fuel premixed with no issues letting them sit, however I keep them full. I have over 5 pieces of Stihl equipment that have had zero issues since switching fuels. And that small orifice that's keeping her from running costs more to find and clean than buying a carb.

 

[scdeerslayer]

Never cleaned a Stihl carb but I've had plenty of success cleaning and rebuilding Husqvarna carbs. Use carb cleaner and also blow out with an air compressor. Are you taking the adjustment screws out and putting them back to the same depth? When I do one I count how many turns to bottom out. Have you tried adjusting the screws either before or after cleaning?

 

[Billrog]

Remove the spark arester.

 

[JRobyn]

I find I get about the same results with running dry or leaving with treated/stabilized fuel. Non ethanol if at all possible. I believe that even "running dry" leaves just enough fuel in critically small places to result in varnish. A strong dose of SeaFoam at the beginning of the new season is terrific to help dissolve and flush out any varnish that does occur. If you can't leave it indoors where temperature and humidity are stable, be sure to leave the tank FULL lest moist air flow in and out and condense in there.

I have had the same peculiar problem with Stihl carbs. In one I worked on, I found the tiniest shred of a red shop rag. The only way it could be seen was under magnification. It evidently moved around with fuel flow. So now I do all my carb work using one of these - 5X LED Magnifier Lamp, Adjustable Swivel & Swing Arm LED Magnifier Table Lamp Light With Glass Lens and Bench Clamp - - Amazon.com

 

[Slowpoke Slim]

I have good luck with just running them dry at the end of the season. I try to never use fuel with ethanol in it as well.

 

[4570Man]

I never use ethanol gas and leave my equipment fueled up year round. I've never had any trouble with this approach.

 

[CalG]

I use pump gas (10% ethanol) and EXPECT those tiny two stokes to be baulky after winter's lay over.

A good 30:1 oil mix late season , to prevent corrosion, and a little mixture screw fiddling on first run of the season has everything right.

A - minus screwdriver and my eyeglasses is all it takes!

You are asking too much to expect nothing to change over a winter. But it doesn't take much to put things right again.