Stihl ms 170 hard starting

[Boomer 87]

Ok im reaching out for a lifeline. I have a friends ms 170. It has a new fuel line and filter, air filter, and carburetor. All parts are oem stihl. If the saw sits for a time it will not start without priming the carb, once running runs perfect and 1 pull starts all day long. Once sitting a spell its back to the same thing, no starting unless primed. Any thoughts or ideas, i have an 017 that acts the same way. Thanks

 

[LonestarStihl]

Ok im reaching out for a lifeline. I have a friends ms 170. It has a new fuel line and filter, air filter, and carburetor. All parts are oem stihl. If the saw sits for a time it will not start without priming the carb, once running runs perfect and 1 pull starts all day long. Once sitting a spell its back to the same thing, no starting unless primed. Any thoughts or ideas, i have an 017 that acts the same way. Thanks

That seems to be all 170's. Mine takes about 7-10 pulls then it's great. I've heard many others say the same thing

 

[Rockjock]

My high mileage 017 is a text book starter and I sell a great many 170's with no issues. What I have found is a plastic intake ring is what is used to hold on the intake boot, it may not be tight and causing issues. Worth a try no?

 

[stevetheboatguy]

For some reason the choke plate doesn't close all the way on the ms170-180's that I have had through.
It's nothing major but you need to do a little playing and fiddling around to get it to close down properly.
Those little 170-180's usually start one or two pulls when the carbs are clean and the choke is closed 100%.

Steven

 

[LonestarStihl]

I will say mine ran better with some seafoam in it. Then went back to just gas and it didn't run as well.

 

[Boomer 87]

Ok ill check the choke linkage see if it can be adjusted. Also the oiler seems anemic, i know they typically are but this one about half throttle no bar or chain it spurts oil then nothing then oil spurt then nothing no constant oil flow.

 

[LonestarStihl]

Ok ill check the choke linkage see if it can be adjusted. Also the oiler seems anemic, i know they typically are but this one about half throttle no bar or chain it spurts oil then nothing then oil spurt then nothing no constant oil flow.

Mine is very stingy on oil but haven't had an issue. I don't use it hardcore either since I have an awesome JD now .

 

[DeckSetter]

For some reason the choke plate doesn't close all the way on the ms170-180's that I have had through.
It's nothing major but you need to do a little playing and fiddling around to get it to close down properly.
Those little 170-180's usually start one or two pulls when the carbs are clean and the choke is closed 100%.

Steven

I had that problem with my 180. You can bend the choke linkage a little so it will engage better. If you bend it too far, it won't stay in the choke position. A little trial and error and it wasn't a tough fix.

 

[Millerhill520]

A lot of people overlook the tank vent on saws. I have had tank vents so clogged that they create tons of pressure, and if not fixed, it can blow a small hole in the diaphragm and make a saw do crazy things until it's figured out. You can tell a clogged tank vent by running the saw a while, and shut it off, turn it on its side, and twist the fuel cap open and listen. If it "relieved" itself, it's got a clogged vent. Sometimes it will do that if sitting for a while closed up. Pressure is pressure.....

Also, if a vent is missing it's little plug in it and leaks, it can lose some pressure and cause a saw to start really hard. Long story short, I guess I am just saying like the member who said to check the plastic rings on the boot, which is great advice, is to give that tank vent a check too.

I discovered my 200t's had crappy vents from the factory, and they sold a vent repair kit which came with a punch to drive the old one out, and replace with a nipple, small line and filter type thing. Those worked 100 times better than any factory vent. I have 17 200t's and almost all of them got that tank vent upgrade when I do a top end.

Other than the tank vent, it could be a plugged screen in the carb. It doesn't take much to clog that little screen.

 

[Boomer 87]

I think it was mostly the choke not closing all the way, adjusted the linkage then it fired 2 pulls. I still think the oilers too anemic.

 

[Jason Stroemer]

I think it was mostly the choke not closing all the way, adjusted the linkage then it fired 2 pulls. I still think the oilers too anemic.

I had the same problem. Hold the choke down all the way and it fired on 3 pulls