Carb rebuild problems

[kugss]

I bought a ms170 that needed some work (http://www.arboristsite.com/chainsaw/177640.htm) I have put new rings in it wouldnt start, so i thought the carb neede a good cleaning. Ibought new gaskets and diaphragm put it all back still no start. I thought i had damaged the crank seals trying to make them sit in their hole so i got new ones and still no start. Take the carb back apart and make sure i have everything in its rite place, plastic card against the carb body and the gasket on top, or side is gasket against the carb and the diaphragm on top make sure the lever is about flush with carb and the screen is clear all back to gether and still no fire. Will run if i pour a little gas in the carb. I also check the fuel filter and line filter is clean and the line has no holes and is not soft. i seems to me that fuel is not getting to the metering side. no real sure whats next other than a hole new carb.

 

[From009to090]

Yep, thats an EPA carb. No high or low adjustments. You have to take it allll apart. Blow it out with Gumout Carb Cleaner spray, then let it soak in carb cleaner or 'spirits' over night. Blow it out again, then reassemble. If it still doesn't run, you just may need to buy a new carb. I hate these carbs with no adjustments.

 

[Fish]

You need to remove the needle/spring/lever too, and hold it up to a light and look through the passage under the needle, blow it out, look again and visually verify that it is clear. Also remove the tiny jet with a screwdriver and clean it, if it won't budge, leave it alone and
clean it as best as you can.

reassemble

 

[ncfarmboy]

Hate them dang non adj. carbs. Changed both of my MS180's to 021-025 adj. carbs. Definately the way to go.
Shep

 

[crane]

have you pressure/vac tested the carb? That will tell you if there are any leaks of if the metering lever is set correctly. It may also help determine if the internal check valves in the carb are good or not. Stihl has really dropped the prices of new carbs(here in Canada, anyways). A complete one should run you $60 or so.