200t help

[bill22]

Hey all,my 200t isn't running so great,it gets just under top speed,then "burps" and dies,idles okay.It ran great until a friend tried to make it run better by tuning it.Any help is much appreciated.

 

[SkwerI]

Sounds like he got the carb out of adjustment. Heck, if you feel like bringing it over to Casselberry (436 and 17-92) this weekend sometime I'll help you get it set up right. They can be a pain with the limiter screws but I have everything here to fix you up. I'll even put the tach on it to set the top speed correctly.

 

[bill22]

Wish i could,but probably not this weekend,but soon definatly.

 

[woodworkingboy]

Maybe you could at least try and turn the adjustment screws back to the factory spec. and see where that gets you...isn't it one turn open for both screws? Clean filter before adjustment.

Oops, limiter caps.....ah so!

 

[Al Smith]

It isn't that big of a deal to pull the limiters off unless they've changed the design .At any rate you most likely could have one of two problems .Either the high speed is just set too lean or you have the same problem with the Zama carb most of us have already experianced . I'll find the link in a sec .

 

[Bermy]

...in a sec...:what:

 

[Al Smith]

Forgot,sorry .Another sec -----

 

[Al Smith]

I can't find that thread but it might be on another forum .

At any rate there's the possiblity that the welch plug in the fuel chamber of the carb might be leaking a tad bit which will cause a slightly lean running condition after the saw warms up .

There's two basic styles of that Zama carb .One uses a triangle shaped welch plug in the fuel chamber and the other does not .I only assumed the ones I had were leaking so I daubed a little Red Loctite around them and it seemed to fix the problem .

I had also assumed I had another one with a crack in it but after Eddie had it tested at Stihls facility in Virginia Beach evidently that was not the problem .At least not on that one .

There is some type of accelerator pump built into that carb but I have no idea where it's at nor what to do to fix it .However from the discription the saw sounds like it's running out slightly lean .

If it were mine I'd attempt to fix it before I bought another because that itty little thing costs about a hundred bucks .

I've got the pictures if it would help,speak up now .

 

[bill22]

pics would be great.

 

[Al Smith]

I couldn't find the pictures I was looking for but this shows the two designs of the fuel chamber I mentioned .If you get the idea of using sealant as I did be very carefull when applying it as to not block off one of the orfices .Use a Q-tip or something very gently .Let it dry over night before using it .Might work,might not.You may have to use a magifying to detect a crack if one in fact is present .

 

[bill22]

Thanks Al,my is a zama carb,said stihl zama 2 on it.I pull the limiter cap to see if i could tune her out,but couldn't,i also discovered the tank vent is missing,so i put a screw in it[temporarily to get some kind of tune].

 

[Al Smith]

Say what,tank vent missing and you blocked it off with a screw .No wonder it doesn't run worth a hoot .

Are you sure it's the tank vent .That saw uses a little breather type thing that sits in the air box compartment .It's out of the way .How in the world could it get torn off ?

 

[bill22]

beats me,it looks like it just plugs into a short hose,ordered one today,plus a new air filter,fuel filter and picked up a plug,if i gotta tune it out,might as well have everything else right.

 

[Cobleskill]

Actually, a sheet metal screw that fits loose in a vent hose, was suggested as a cheap alternative for the sintered bronze vent. Not loose enough to fall out, but not so tight to make a seal.

 

[Al Smith]

Well yes on a regular tank vent ,old style .However on the 200T and most more modern Stihls they use that breather thing that vents into the filter chamber I suppose in order they don't plug with chips and stuff . I think that's a great idea that Stihl came up with .

The old vents could get torn off for one reason or another but you'd have to work at it to tear loose a 200T vent because of the way it's made .

 

[Al Smith]

Another thing though .That little saw uses that "intellacarb " gizmo .The atmospheric vent for the metering diaphragm vents into the air filter .If the filter becomes plugged the saw doesn't reach full power because the deflection of the diaphragm is limited .Therefore if that vent or the filter becomes plugged the saw obviously would not run at it's full potential .The problem could just as simple as that .

I would think that if what I descibed is correct then the saw would act about the same as one with a dried out diaphragm and therefore not be able to attain full RPM which it sounds like what's happening .Does run at a lesser than full though .

 

[MCW]

I can tell you what was done to my inconsistantly running 200T and it worked a treat. The dealer had no end of trouble with mine as the saw would hold tune one minute then simply go off the reservation 2 seconds later. He epoxied up the accelerator pump as they cause known issues and aren't really necessary. It was still playing up after that and in the end he replaced the entire compensating carby and backing plate to a new non compensating carby and backing plate. This saw has not skipped a beat since and went from the most troublesome, frustrating saw I owned to one of my favourite, most impressive saws. Stihl did a lot of things to the 200T carby that really wasn't necessary and instantly gave an awesome little saw a quite awesome faulty carby reputation.

 

[SkwerI]

Replacing the carb is always my 'repair of last resort', but it's definitely worth it if nothing else works. Sometimes it's better to plunk down $100 and get back to work.

 

[MCW]

Replacing the carb is always my 'repair of last resort', but it's definitely worth it if nothing else works. Sometimes it's better to plunk down $100 and get back to work.

Exactly right. In terms of a work saw $100 isn't much for a bit of reassurance and all up the repair cost around $200. At least I now have a reliable saw again.

 

[Al Smith]

Well yes I can relate but again it boils down to your tolerance level .Fact is at the moment Mrs Smiths' printer isn't working properly .

I'm sure 90 percent of the posters on this forum could figure that frustrating contraption out in about 5 minutes flat .That would be about 3 minutes over my patience on a puter though ,off to the store to get up another--about 100 bucks I suppose .

I can keep my cool on a saw and some can keep their cool on a puter,simple as that .

Aha,Mrs. Smith is a detective and found a spring loose just after I posted so all is not lost .I think I'll keep her .

 

[Al Smith]

Aha Ha .I did repair Mrs Smiths' printer and kept my cool . Another mile stone .

Now since a grumpy old dog like me can learn a new trick maybe some of you younger more patient types can get with the carb thing, maybe not .

 

[MCW]

Or with something like the 200T carby you can just leave it to the dealer because some of us don't have all day to work it out
I have rebuilt saws, can swap a P&C in about 1/2 an hour, but when the carby on my 200T played up, and even the dealer couldn't work out what was wrong with it, I didn't have a hope

 

[bill22]

I can and have fixed carbs before,but i see posts about intellicarb and just feel like its outta my skill set,so off to a dealer,if he can't fix then I'm gonna buy a new husky climb saw.

 

[Al Smith]

If you remove that little rubber nipple that goes from the air box to the carb atmospheric vent it un intelegises the "smart " carb .At that point it works just like any other .Plug the hole in the air box if you do that though . I doubt that's the problem though .

 

[woodworkingboy]

Is there any big advantage to the smart carbs, I mean for the consumer?