Occasional hard starting

[Mick]

Yup, I am a homeowner. I do occasional volunteer chainsaw work for the hiking club on the trails, for the land trust in their woodlots and for friends. Over the decade or so that I have had it my Stihl MS 211 has rarely run out of fuel on the job - usually there has been a single tree and/or a few small spots requiring attention. But recently I have done a few all-day plus come-back-the-next kind of jobs so refueling part way through the day became usual practice.

Recently I have had some trouble restarting my chainsaw after refilling the oil and fuel part way through a job. I use a warm start procedure - no choke. The symptom has been similar to if it were flooded [pull throttle and it just sputters, several times] so I used my flooded procedure to restart it: remove the air filter cover and filter, let it air out then replace. Choke off, hold trigger and lever on while pulling the starter rope; it starts after a few pulls. I have not had to remove/dry spark plug, empty the combustion chamber yet

The last time this happened I had an insight - perhaps it is not flooded at all, but instead the carburetor is completely empty. I had this thought because I see no practical reason why it should be flooded. When it actually does run out of fuel I typically restart it a couple of times only to have it sputter out right away before I really get that it really does need refueling; so maybe the fuel bowl/combustion chamber is just super empty?

So, my question is - What is happening? Is it really flooded because I had it on its side while I topped up the oil and fuel? Or is it hard to restart because it is hard to get fuel back into the combustion chamber? Or perhaps I should just give it some choke, half maybe? On my most recent job I did not have this problem - I re-fueled and it just started normally.

 

[coffeebrk]

What have you done maintenance wise?
Air, fuel filters ?
Plug?
Carb kit ?
Hoses ?
Carb adjustments?

 

[Mick]

What have you done maintenance wise?
Air, fuel filters ?
Plug?
Carb kit ?
Hoses ?
Carb adjustments?

Good questions. Good list of stuff for me to review, check out and think about.
Thank you
Mick

 

[irhunter]

If you ever think the saw is flooded, pull the spark plug. Is the plug wet with gas?

You are right...thinking about hard starting should start by knowing if the saw is flooded or short on gas.

Roy

 

[Farmer_Nate]

How old is the saw?
If it is a few years old, and if has ever sat much, it could need a carb cleaning. Gunk piles up inside saws that sit sometimes, especially if fuel stabilizer isn't used.
I'd try spark plug first.

 

[TheJollyLogger]

Yup, I am a homeowner. I do occasional volunteer chainsaw work for the hiking club on the trails, for the land trust in their woodlots and for friends. Over the decade or so that I have had it my Stihl MS 211 has rarely run out of fuel on the job - usually there has been a single tree and/or a few small spots requiring attention. But recently I have done a few all-day plus come-back-the-next kind of jobs so refueling part way through the day became usual practice.







Recently I have had some trouble restarting my chainsaw after refilling the oil and fuel part way through a job. I use a warm start procedure - no choke. The symptom has been similar to if it were flooded [pull throttle and it just sputters, several times] so I used my flooded procedure to restart it: remove the air filter cover and filter, let it air out then replace. Choke off, hold trigger and lever on while pulling the starter rope; it starts after a few pulls. I have not had to remove/dry spark plug, empty the combustion chamber yet 







The last time this happened I had an insight - perhaps it is not flooded at all, but instead the carburetor is completely empty. I had this thought because I see no practical reason why it should be flooded. When it actually does run out of fuel I typically restart it a couple of times only to have it sputter out right away before I really get that it really does need refueling; so maybe the fuel bowl/combustion chamber is just super empty?







So, my question is - What is happening? Is it really flooded because I had it on its side while I topped up the oil and fuel? Or is it hard to restart because it is hard to get fuel back into the combustion chamber? Or perhaps I should just give it some choke, half maybe? On my most recent job I did not have this problem - I re-fueled and it just start normally.

Stihls are notorious for being finicky about a warm start.... to choke or not to choke, that is the question, lol. The old standby, not OSHA approved, but it always seems to work for me, is to rest the tip on a log, full throttle no choke and pull until it starts, then clear it out.

 

[irhunter]

"Stihls are notorious for being finicky about a warm start"

Really? I have never found that to be the case. Warm start issues, which I have seen, have always been caused by something wrong with the particular saw...or, operator error. Not brand- or model-specific.

Roy

 

[TheJollyLogger]

"Stihls are notorious for being finicky about a warm start"







Really? I have never found that to be the case. Warm start issues, which I have seen, have always been caused by something wrong with the particular saw...or, operator error. Not brand- or model-specific.



Well, You're in Maine, it is definitely more of a problem in the summer.



Roy

 

[irhunter]

True about Maine. But, I have run saws in a pretty wide range of temperatures in quite a few states.

Not in Texas, however.

The OP is from Canada....where I have also run saw. But, not in Ontario.

Roy

 

[ericm979]

So, my question is - What is happening? Is it really flooded because I had it on its side while I topped up the oil and fuel?

It's not flooded. It's low on fuel. The carburetor's float bowl is empty and the fuel lines have air in them. It's not because it was on its side. Saw carbs are "any position" carbs that work the same in any orientation.

Saw carbs have a pump which is activated by pressure changes in the engine crankcase. The pump sucks in fuel from the tank and there is often also a return line to return excess fuel to the tank.

A primer bulb could be used to pump fuel from the tank through the carb and out the return line to refill the carb and purge air. But Stihl saws usually do not have the primer bulb though other Stihl equipment like backpack blowers sometimes do. So you have to either pull the starter a few times to activate the pump to get more fuel into the carb, or if there is enough fuel, start the engine and let the pump purge the air from the lines.

Most saws start running funny when the tank is low on fuel. They'll idle high (because the mix is lean), or not rev out, or rev too high, or hesitate. If you can recognize the signs that your saw makes when it's low on fuel and stop to refuel then rather than waiting until the engine dies, there will be less air in the fuel system and it will restart easier and run better after filling up.

 

[sean donato]

Like the guys have suggested, go over the saw and make sure everything is in good shape, but really you need to learn when to stop and refuel installed of letting it run out. It gives several signs, but just using it you learn how much cutting you can do with a tank. I have a few old saws that are bears to get started if you let them run dry. My trusty ported 359 Is one of them. It takes a hot minuet to fire it back up once it sucked itself dry.

 

[TheJollyLogger]

As usual, technique....

 

[Colonel428]

Also a good technique when restarting a warm saw is to put your knee and weight on the saw to secure it to the ground and then squeeze the throttle wide open with one hand a pull the starter cord with the other. Someone else on here (can't remember who) recommend trying that and it's worked for me many times where I thought the saw wasn't going to refire at all for me...