Stihl MS 290 Chainsaw Won't Start

[nobbyv]

Hope this is OK here...

Have a 8-9 year old MS 290 I bought new. Low hours overall. Put about 3 hours on it two weeks ago where it worked fine, went to start it the other day and...nothing. I thought I had no spark (because I was trying to ground out the plug on the carb instead of the cylinder), so I replaced the ignition module and spark plug. Needless to say, spark is now fine. New air filter, new 2-cyc mix. What is weird is after sitting for a few days, it will usually start the first time ONLY. For example, after bolting it back together after replacing the ignition module, it fired on the first pull. Ran it for 10-15 seconds, then noticed the chain was loose so shut it down. Tightened the chain, went to restart, and ...nothing again. It's never been straight gassed. Cleaned the carb thoroughly while I had it apart for the ignition module. Any thoughts?

 

[bigredcornhead]

Cracked fuel line some where? Pick up filter clogged?

 

[nobbyv]

Cracked fuel line some where? Pick up filter clogged?

The plug is wet after trying to start it, so it seems to be getting fuel...

 

[redmondjp]

If the plug is wet, it may be getting flooded. Spray the plug with some kind of solvent (carb cleaner, brakleen, etc.) and blow it off with compressed air. Leave the ignition switch off and the spark plug out, choke off, and throttle fully open, and rapidly pull the starter cord 8-10 times to clear out the crankcase and combustion chamber. Then reinsert the plug and see if it starts then.

 

[nobbyv]

If the plug is wet, it may be getting flooded. Spray the plug with some kind of solvent (carb cleaner, brakleen, etc.) and blow it off with compressed air. Leave the ignition switch off and the spark plug out, choke off, and throttle fully open, and rapidly pull the starter cord 8-10 times to clear out the crankcase and combustion chamber. Then reinsert the plug and see if it starts then.

You're onto something with the flooding. The way the guy that sold me the saw (who's been a Stihl dealer for 25+ years) taught me was to put it in full choke and pull until it "caught", then choke it down and pull again until it was running. This always worked in the past: generally, 3-4 full choke pulls would get it, then it would start. After some research, it looks like 3-4 pulls may actually be too much for this saw, and I was potentially ALWAYS flooding it (just not enough to keep it from starting).

A few minutes ago, I tried two full choke pulls only, then choked down and on the second pull it fired right up. Shut it down, repeated, same. Shut down, repeat, same.

So I don't know what changed (possibly an ignition coil is slightly out of adjustment?), but it now seems the saw wants only a pull or two at full choke before starting.

 

[larry_g]

I have a 290 and never choke it after the first start of the session. A warm saw should start without a choke.

lg
no neat sig line

 

[Farmall450]

If you pull one too many times after it burps (on full choke) you're not going to get it started.

 

[metlmunchr]

I've got a Stihl saw and blower, and, if you don't follow the magic starting procedure, both of them will flood every time. Never have seen another engine of any brand that's as finicky to start as a Stihl.

 

[mcbane]

Does NH follow CA fuel formulation requirements? If so your fuel line is rotten and you need to replace it every year.


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