MS180 Adjustable Carb

[WTO]

I know this an old thread but I just discovered the non-adjustable POS carb my 2 year old saw would not run. It will crank but dies when you hit the gas. I figured it would be a simple adjustment....
Is there not an option to install a larger jet in the factory carb to correct the lean condition? I haven't pulled it apart yet, seems like that would be a simple fix?

 

[rupedoggy]

I figured it would be a simple adjustment....

Well since this is your first post I am going to be nice and say, when you figure out the simple adjustment share it with the other 20 that have 017/018 troubles on here. BTW the screws for some of these are left hand and increase fuel with a clockwise turn. Good luck

 

[WTO]

Well since this is your first post I am going to be nice and say, when you figure out the simple adjustment share it with the other 20 that have 017/018 troubles on here. BTW the screws for some of these are left hand and increase fuel with a clockwise turn. Good luck

I took it apart, cleaned all the sawdust particles out of it, and it runs ok. I did bend the float arm a small amount to try and get more fuel into the bowl. It still has a lean stumble when you first hit the gas. I've spent a few hours looking and cant find a larger jet. Looks like the one in it is a .42. I found a Stihl parts list that shows the jet as P/N 4137 121 5601. Anyone know where I can get a .44 or .46 from? Searching some of the numbers off the carb, it I think it is model RB-27? The factory filter on these are junk, it lets too many fine particles by. Some of the fine dust was inside the carb, behind the diaphragm. I bought this saw new, really haven't run it that much. I know is a low end model but expected a little more from Stihl. If I had it to do over I would have found another old one and rebuilt it. I disassembled the carb, all the way down to the needle & main jet, didn't run across any LH threads?
I've got an old McCullough 10-10 that is 40+ years old, and a 610. Both are more dependable than this 3 year old saw.

 

[94BULLITT]

I have a 170 that is 7 or 8 years old and it has been problem free. You shouldn't bend a metering lever unless you have the proper tool to adjust it. What do the diaphragm look like? Are they wrinkled? How long has the saw been sitting?

Sent from my SM-G950U using Tapatalk

 

[WTO]

I have a 170 that is 7 or 8 years old and it has been problem free. You shouldn't bend a metering lever unless you have the proper tool to adjust it. What do the diaphragm look like? Are they wrinkled? How long has the saw been sitting?

Sent from my SM-G950U using Tapatalk

It may have sit 6 months since its last use. I know there is a spec on the float arm, I was just trying some options to see if it would run & it did. The diaphragm was like new, no wrinkles, soft & pliable. Hard to believe there is nowhere to get a larger jet....
My big saws sit for a year or more and I rarely have an issue with them. My 610 is flooding now, its been 15 years since the carb was build on it, so I can't complain. I knocked down a big pine last week, and both the saws I had with me quit. My whole reason for buying a new saw a few years back was for reliability.....Guess I should have taken my Husky too but I didn't think I needed 3 saws for one tree

 

[94BULLITT]

If it has sat for 6 months the carb probably needs rebuilt, and you can get a new one so cheap they are not worth rebuilding. Now is a good time to put a WT215 on it. I would also put a new fuel filter on it. A muffler mod will make it a completely different saw.

https://www.ebay.com/itm/303298170419
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[Lee192233]

I have a MS180C. I was cutting with it earlier this year. I noticed it stopped 4 stroking and was revving really high. Checked with the tach and I saw 15500 and shut her down. I cleaned carb and replaced the fuel filter and line. Same thing. After finding this thread I decided to buy the WT215 carb and install it. Best damn thing I ever did! I installed the carb (instructions are in this thread), opened up the muffler, new air filter and spark plug. It's a whole new saw. After tuning it she call pull a 14" 3/8 lp buried in ash. Used to be I had to keep pretty light pressure on it. Now I can put a little pressure on it and it keeps cutting.

Good luck,
Lee

 

[WTO]

I have a MS180C. I was cutting with it earlier this year. I noticed it stopped 4 stroking and was revving really high. Checked with the tach and I saw 15500 and shut her down. I cleaned carb and replaced the fuel filter and line. Same thing. After finding this thread I decided to buy the WT215 carb and install it. Best damn thing I ever did! I installed the carb (instructions are in this thread), opened up the muffler, new air filter and spark plug. It's a whole new saw. After tuning it she call pull a 14" 3/8 lp buried in ash. Used to be I had to keep pretty light pressure on it. Now I can put a little pressure on it and it keeps cutting.

Good luck,
Lee

You talked me into it, I have one on the way. Do I really need to tach the saw or just tune by sound like I always have? I dont have a way to tach the saw that I'm aware of, is it time for another tool?

 

[rupedoggy]

Don't buy cheap saws

 

[Jasonrkba]

Tachs are subjective. Some swear by them some don't. I adjust in the cut.

 

[Lee192233]

Don't buy cheap saws

My price of entry into my MS180 was $0. I also have a 026 and MS460. I've used the 180 for 8 years without a problem. I figured it would be fun to tinker with it a little. For $30 and a little time I gave it adjustability and a bit more power. If anything serious happens to it I will part it out.

Tachs are subjective. Some swear by them some don't. I adjust in the cut.

I got a tach because I wasn't confident in what I was hearing. I quickly figured out I had my saws way too rich. Just gave me some confidence in leaning them out. Now I adjust mostly by ear. I just use a tach to confirm what I'm hearing now.
Lee

 

[WTO]

Finally got around to putting the WT-215 on last night. Even with a screw behind the throttle trigger you can't achieve WOT (probably 85-90%), because the throttle shaft bell crank hits the black piece shown. I assume its there as an insulator? Taking it off resolves the problem and does not appear to uncover anything that needs to be covered. Has anyone removed this to gain the necessary clearance.

 

[Lee192233]

Finally got around to putting the WT-215 on last night. Even with a screw behind the throttle trigger you can't achieve WOT (probably 85-90%), because the throttle shaft bell crank hits the black piece shown. I assume its there as an insulator? Taking it off resolves the problem and does not appear to uncover anything that needs to be covered. Has anyone removed this to gain the necessary clearance.

I'll take a look at mine tonight. I don't recall that piece being in mine. My saw is probably 10-12 years old, maybe they didn't have it then.
Lee

 

[Lee192233]

Checked my 180 and there is no sign of that piece. I wonder what it's purpose is?
Lee

 

[WTO]

Checked my 180 and there is no sign of that piece. I wonder what it's purpose is?
Lee

I just left it out. I was going to cut out the area, where it hits, but was tired of messing with it. Getting the brass plug out of the impulse passage, on the new carb, was the most difficult part by far. I don't see how you guys are accessing the H/L screws once the saw is reassembled. I had to bolt the carb up with spacers, no air box, and run/adjust it. Once I put it all back together its too rich with the filter restricting it. I'll have to take the air box back off and lean it out some and it should be good to go. For anyone else researching this, a 3/8 plug is perfect to plug the sense hole in the air box. Also opened the muffler up some.

 

[Lee192233]

I just left it out. I was going to cut out the area, where it hits, but was tired of messing with it. Getting the brass plug out of the impulse passage, on the new carb, was the most difficult part by far. I don't see how you guys are accessing the H/L screws once the saw is reassembled. I had to bolt the carb up with spacers, no air box, and run/adjust it. Once I put it all back together its too rich with the filter restricting it. I'll have to take the air box back off and lean it out some and it should be good to go. For anyone else researching this, a 3/8 plug is perfect to plug the sense hole in the air box. Also opened the muffler up some.
View attachment 838326

I carefully estimated where the screws lined up with the cover and drilled holes.

 

[Jawby]

Thank you to blsnelling and everyone for this info! I now have an adjustable wt215 on my ms180c having read, and reread this thread and watching the "sammish sawworks" youtube "how to ms170 ms180 w/walbro 215" video over and over. I ordered my carb via amazon and paid just short of $50 delivered... fast and genuine in 2022... is what it is. I registered with arbosite because of this thread... thank you all!

 

[a. palmer jr.]

I don't have any other carbs here to compare so I started looking at eBay pics. 021, 023, 025 carbs look like they might be a direct swap.

290, 310, 390 carbs looks similiar as well. Looks like all they might require is reversing the choke rod.

Yep, they're a direct swap and adjustable as well. You might have to modify the side of the saw next to the air box in order to adjust the screws without removing the cover. I've done this several times and the 025 carb works great on an 018.

 

[Mparko93]

They are closed until Feb 7 for the new year but here's the link.

http://www.ebay.com/itm/STIHL-Chain...778?pt=LH_DefaultDomain_0&hash=item5af487d722

I know it's been a while since this was posted, but any chance you have the name of the store you got this part from? The link is inactive and I really want to get a carb that will pop straight in! Cheers

 

[GenXer]

I know it's been a while since this was posted, but any chance you have the name of the store you got this part from? The link is inactive and I really want to get a carb that will pop straight in! Cheers

Farmertec.com has them.