Stihl MS250: end of the road?

[HarleyT]

Stihl put many different carbs on that saw series. They will interchange, but the e-z start series had the extra nipple for the primer/purge system.
Here is the model of the carb I have.

C1Q

 

[bitsumishi]

After the needle is removed, hold the carb body up to a light and look through the hole to the screen on the other side, and see if the passage is choked up with gunk.

With the carb off, go back and closely inspect the fuel line again, look for cracks @ where it goes into the tank, and for excessive mooshiness on the part that sits in the gas, ans rips/tears there as well.

Thanks very much Harley. I followed your instructions and I could see light through the other end: shone a flashlight into it and it looked clean.
I took the fuel line to the tank off earlier to have a good like at it. It's a bit pinched at a couple of places but other than that there were no cracks or deterioriation of the rubber that I could see.
I will call the Stihl dealer tomorrow and get a price for a new carby and fuel line.

 

[HarleyT]

S76c

But the Stihl # is 1123-120-0603

 

[HarleyT]

Pinched fuel line is a bad thing.... It can pinch if it softens with age/fuel contamination.

 

[Khntr85]

I hate rebuilding the 250 with the primer bulb....to much tubing, I just take it out and make them a standard carb

 

[bitsumishi]

I hate rebuilding the 250 with the primer bulb....to much tubing, I just take it out and make them a standard carb

No primer bulb on mine.

 

[bitsumishi]

I think the part number reads S85B 644A. I have a feeling mine was an easy start version but the manual is long since gone.

 

[Khntr85]

Take a picture of the starter recoil we can tell real quick

 

[bitsumishi]

Ok I found the part numbers: Zama C1Q-S85B and Stihl 1123 120 0607. Genuine retails in Australia around $100 USD.

 

[Khntr85]

Oh my that's nuts...I would be trying to clean that one...it should work, if not buy AM...


Since parts are so crazy high there, it's to expensive to just throw parts at it....just replace what is needed...

 

[bitsumishi]

Oh my that's nuts...I would be trying to clean that one...it should work, if not buy AM...


Since parts are so crazy high there, it's to expensive to just throw parts at it....just replace what is needed...

Problem is that the part numbers only come up worldwide with repair kits or genuine units, not aftermarket replacement units. I guess that they only used this in the UK and Australia.

 

[HarleyT]

Get a price on the one I put up.


Here is a section out of our pricelist, it refers your number to the one I have.


1123 120 0602 CARBURETOR (MS250C) 64.49


1123 120 0603 CARBURETOR (MS250) 21.99

1123 120 0604 CARBURETOR (MS210) 21.99

1123 120 0605 CARBURETOR 21.99

1123 120 0607 USE: 1123 120 0603 83.49

1123 120 0609 USE: NLA 59.49

1123 120 0610 USE: NLA 69.49

1123 120 0611 CARBURETOR 71.49

1123 120 0613 USE: NLA 85.99

1123 120 0614 USE: NLA 55.49

1123 120 0616 USE: NLA 69.49

1123 120 0619 CARBURETOR C1Q-S90 62.49

1123 120 0620 CARBURETOR 21.99

1123 120 0629 Carburetor 36.99

 

[HarleyT]

I can sell you the one I have, looks like first class mail is $13.75

 

[dougand3]

Good info from HarleyT and Khntr85 . If cleaning doesn't work, go AM. ebay.au will have AM clones for $7 AUD. Some Zama, some Walbro clones. I like the Walbro - 4 screws for metering side and H-L are adjustable. The H-L screws may be a little different place and may not line up with black carb grommet, but no biggie. You just need to match 3 things: Choke linkage, throttle linkage, impulse hole.
Compare your carb and an AM carb -
eg: http://www.ebay.com.au/itm/Carb-Car...097721?hash=item465a623ab9:g:JDQAAOSw44BYDWB1

 

[Matto]

Did you check the setting of the metering lever? The end of the lever should be flush with the carburetor deck.

If fuel leaks out by putting the saw on her side, it means the needle doesn't close tight even if the lever is at full upper position on the metering diaphragm.

 

[SteveSr]

If you are going to change the carb you might consider a fully adjustable Walbro WT-215 which would go nicely with a muffler mod if you have an overly restrictive muffler (post pictures with the screen cover removed). The 215 came on 025's, the 250s predecessor.

 

[bitsumishi]

If you are going to change the carb you might consider a fully adjustable Walbro WT-215 which would go nicely with a muffler mod if you have an overly restrictive muffler (post pictures with the screen cover removed). The 215 came on 025's, the 250s predecessor.

 

[SteveSr]

View attachment 575089

That is the non-restrictive muffler. Much better than the EPA version we get over here. I don't know if you would get much more benefit from further modifications other than more noise.

As far as carb replacement goes be cautious of any U.S. market carbs as they were designed for the restricted mufflers and won't flow enough gas with yours. Even though adjustable the adjustment range can be severely limited. Look into a genuine Walbro WT-215. Even though these were used on Stihls they are NOT Stihl specific and can be found at any dealer that sells Walbro.

I recently converted a couple of MS210s to the old muffler and 215 carb. Carbs were about $25-30 U.S. Everything works fine when properly tuned. I believe that you will also have to get a new rubber grommet to go around the adjustment screws on the 215 but they are available.

 

[HarleyT]

Well, just get the 1123-120-0605 then, if you want the Walbro, it is the same price from Stihl. It is easily bought on the US market as well, so I doubt that there is any difference.

 

[andrethegiant70]

If you are going to change the carb you might consider a fully adjustable Walbro WT-215 which would go nicely with a muffler mod if you have an overly restrictive muffler (post pictures with the screen cover removed). The 215 came on 025's, the 250s predecessor.

Indeed, I think this is the ticket. I don't know about the "Easy Start" thing, but the 215 was the original carb... and the best match for this saw. There's a possibility, depending on your top cover, that you might need to drill a hole for access... easy peasy.


Here's a new one....

http://www.ebay.com/itm/WT-215-WALB...297190?hash=item3f78a93ea6:g:VCEAAOSwo4pYiM0E