My stihl chainsaw won't start.

[davescatt]

Hi All, One of my stihls ms170 14inch, I have put a new coil in it ( very good spark ) also a new plug. but it won't start:thumbdown:, I've taken filter holder off,looked at carb ( but not messed about with the carb ) does not seem to be getting any petrol, as when I take plug out it's dry. there is no fuel jet what I can see what I can clean. any ideas:thumbup: Thanks all.

[R Mac]

Did you check/clean the fuel filter? if not start there, open the fuel cap, fish out the fuel filter by hooking the fuel line with a piece of stiff wire and pulling it out through the filler neck. Wash it with clean petrol (not premix) or with carb cleaner, check that the fuel line isn't split/kinked and when you put it back in the tank make sure the filter can drop freely down to the bottom of the fuel tank.

 

If that doesn't work I'd pull the fuel hose off the carb and spray carb cleaner into the carb fuel inlet. If none of that works you'll need to strip the carb.

Edited December 9, 2015 by R Mac

[Sawchip]

Hi All, One of my stihls ms170 14inch, I have put a new coil in it ( very good spark ) also a new plug. but it won't start:thumbdown:, I've taken filter holder off,looked at carb ( but not messed about with the carb ) does not seem to be getting any petrol, as when I take plug out it's dry. there is no fuel jet what I can see what I can clean. any ideas:thumbup: Thanks all.

 

Bit more background would be useful..Did the saw stop and you changed the coil in the assumption it was at fault? Basically what were the saws issues that led to this.

[davescatt]

Thanks for that r mac,It's got no kinks in pipe and I made sure it was at the bottom of tank, I will try that. cheers.

Edited December 9, 2015 by davescatt

[davescatt]

Bit more background would be useful..Did the saw stop and you changed the coil in the assumption it was at fault? Basically what were the saws issues that led to this.

 

Thanks sawchip, It was starting a bit sluggish,not like it always started,( straight away ) so I decided to put a new coil and plug on it, I get a very good spark at plug,but it does not want to know about starting. Cheers.

[harrythecat178]

Check flywheel key, its part of flywheel and if snapped it will never run although still gives a spark

[peatff]

Put some fuel down the plug hole and if the timing is out you might get some interesting backfires

[R Mac]

If the spark plug is dry it isn't getting fuel, try the simple things before digging deeper and making things worse.

 

As Peatff says, take the spark plug out, inject a little petrol into the cylinder, re-fit the plug and give it a try. If the ignition system is working it should start but obviously won't run for long.

 

In short you need spark and fuel, before you start looking deeper.

[spudulike]

If you pull the saw over saw 20 times with the choke on and the plug is dry then it must be a fuel issue.

 

I would make sure that the choke flap is fully closed when the choke is put on.

 

Other than that, the favourites are the internal gauze strainer in the pumping section of the carb and also check the metering arm height under the diaphragm. Both will cause this fault!