New Carburetor?

[user 122190]

How do you know when you are ready to replace the stock Carb?

I had some bogging issues last year and the year before. A rebuild solved that. Now there is a big hesitation going from idle to WOT. Not a biggy, just annoying. I suppose I am ready to R&R the carb from the ms290. After 10 years, I guess it is time. Right?

 

[Woodslasher]

How do you know when you are ready to replace the stock Carb?

I had some bogging issues last year and the year before. A rebuild solved that. Now there is a big hesitation going from idle to WOT. Not a biggy, just annoying. I suppose I am ready to R&R the carb from the ms290. After 10 years, I guess it is time. Right?

I only replace a carb if a cleaning/rebuild won't make it work right, the rods are loose, it won't hold pressure, or it's a cheap Zama. I never have any success with rebuilds in the tiny Zama ones, plus they're pretty dang cheap.

 

[user 122190]

I have a cheap replacement carb that I will pop in tomorrow. First I will attempt to tune it, but in the past that wasn't the problem, nor was the air filter, spark plug, fuel, muffler, etc.

I fuss with the low adjustment needle, but pop in the Chinese replacement soon after.

 

[Mad Professor]

Fatten up/richen the low screw (turn CCW) a bit if bogs when opening the throttle

 

[cscltd]

Ms290s are notorious for cracked fuel lines as it exits the tank, sometimes cracks are hard to notice

 

[user 122190]

Ms290s are notorious for cracked fuel lines as it exits the tank, sometimes cracks are hard to notice

Wouldn't the fuel be seen and smelled?

 

[user 122190]

Fatten up/richen the low screw (turn CCW) a bit if bogs when opening the throttle

I'm pretty sure I am at the limiter cap limits. I have been reluctant to remove them. Perhaps now is the time.

 

[J D]

Wouldn't the fuel be seen and smelled?

Not necessarily, sometimes it will just allow air in

 

[Harmon]

I just replaced an impulse line on a buddy's 290 and while it did run finally it got a lot better after also replaced his 12 year old fuel filter...

 

[user 122190]

I just replaced an impulse line on a buddy's 290 and while it did run finally it got a lot better after also replaced his 12 year old fuel filter...

Yeah, I might as well change out all the lines too.

 

[user 122190]

There was an 1/8 to a 1/4 turn on the low speed screw. Seemed to act better. I'll know for sure tomorrow when a neighbor and I go out and cut up some wind downed trees.

 

[lone wolf]

I'm pretty sure I am at the limiter cap limits. I have been reluctant to remove them. Perhaps now is the time.

If you didnt remove the caps when you last rebuilt it you cant blow out that passageway. Remove ,blow out with carb cleaner not compressed air and try again.

 

[user 122190]

I did order some Carburetor Cleaner Tools. I'll get into the tiny orifices and give them a good reaming, before giving up on the OEM carb. The fact that the H/L adjustments do make a difference tells me that they are still mostly fine. Some light scraping and polishing ought to bring them back to 100%

https://www.amazon.com/gp/product/B07TM4WYG4/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

[bayard]

could hi psi air, hurt a carb. i had a ms 260 carb i could not get it right .it has a china carb now. better but not like new.

 

[lone wolf]

could hi psi air, hurt a carb. i had a ms 260 carb i could not get it right .it has a china carb now. better but not like new.

Yes air at high pressure can wreck check valves.

 

[user 122190]

I spent 2 hours this morning cutting up wind blown down fall. The ms290 ran better, but not good enough. I'll go at it with the Carb Cleaning Tools expected to arrive this Saturday. If that doesn't bring it back to 100% then new Carb R&R plus all the hoses.

Saw was cutting up the wood in a most greedy manner. Freshly sharpened chain, nothing special, just regular upkeep of a few strokes per cutter, but it was hungry for wood. This saw, barring some tragedy, is going to last a long long time.

 

[Joel D'Angelo]

029/290's are an underated saw. Mine, which I am parting with, will not even slow down much with the 20" bar buried in oak.

 

[user 122190]

029/290's are an underated saw. Mine, which I am parting with, will not even slow down much with the 20" bar buried in oak.

My 290 has been a work horse. I have never found a reason to find fault with it. Bought in 2012, extra chain, Stihl 6-pack of ultra 2 stroke oil, a gallon of Stihl B&C oil for under $400.

So $40 a year, or $4 a cord, yeah I gots my moneys worth, and still saving me fat stacks of cash.

 

[user 122190]

My carb cleaning tool came in today. Not sure if it was a waste of money or not. I did remove the limiter and the screw for the low speed adjuster, probed it and blew that out, so maybe that is a positive thing. One thing I did learn is once the limiter is removed don't bother putting it back. I did and could not get it to idle right. Removed the limiter cap again, and got it tuned in an instant. I don't know if the cap was slipping on the screw or what, but the cap is for novices. When you get to the point were the caps need to come off, you know enough to adjust and tune the carbs and don't need the safety of the limiters. IMO.