Stihl MS 311 Won't Start

[DECJ]

New member here.

Here's the deal. Firewood cord costs have gone up so much over the last 12 years in my rural area that my wife and I decided to get a larger chain saw and go get our own firewood. We had hoped to do this last fall, so I bought a new Stihl MS 311 saw with an 18" bar in September 2010 from a dealer in Grand Junction, Colorado. The guy put new gas in our saw, started it up, and thoroughly demonstrated it for us. Unfortunately, a string of other commitments cropped up and we lost our window of opportunity for getting our firewood before winter set in. So, in December, I emptied most of the gas that was in it from September, ran it until it quit and put it away for the winter. Then in early June, I put new 50:1 gas in (with Stabil) and the saw started right up and ran fine.

We planned to head out today to finally get our firewood for this winter, so in preparation yesterday, I went to fire-up the 311 and got nothing. It just acted dead with no life in it and no indication that it was even trying to catch and run. I tried starting it with full-choke, half-choke, and just in "I". Nothing. I removed the spark plug twice and while there was a fuel smell associated with the open cylinder head, the plug was not fouled or overly wet with fuel. Nevertheless, I blew off the spark plug electrode area and the open cylinder head with compressed air. I then went back to trying to start the saw on all "Master Control" lever positions and there still was no indication that the saw was going to start.

I decided to take the saw in to our more local Stihl dealer in Moab, Utah this morning. However, before doing so, I decided to check for a spark. After removing the plug and securing the spark plug boot, I turned over the engine, but I saw no spark with the original spark plug (with grounding-out the threaded portion against the outside of the cylinder head). I then used a new spark plug and still didn't see any spark. So, I thought this must be the problem.

I then dropped off my saw at the local Stihl dealer and found out that their mechanic was on vacation and wouldn't be back until Monday. However, after we got back home, the young guy we left our saw with called and said he got the saw started and that it was running fine. He said that on general principle, he changed out the gas, and while doing so, he also found that the fuel pickup body had shifted upwards in the tank. So after straightening that out and putting the new gas in, he said it started right up. Go figure.

Anyway, we picked it up this afternoon (no charge), took it home, and continued to get ready to head out tomorrow for our firewood. I then decided to start up the saw, and guess what? Nothing. Same exact stuff I encountered yesterday. I went through the same drill and I must have pulled that starter rope at least 100 times and still nothing. I again checked for a spark and still saw nothing there.

Obviously, I am going to return my saw to our local Stihl dealer tomorrow or Friday for their mechanic to trouble-shoot, but in the meantime, does anyone have any words of wisdom as to what likely may be wrong, or if there is anything else I should be trying to do from my end? While I acknowledge that the saw is a year old (2 weeks beyond the warranty period), I am understandably pretty disappointed that a fairly expensive Stihl chain saw that has only been started half a dozen times and never used to cut any wood is currently in this condition.

Thanks in advance,
Don

 

[Fish]

Using old fuel is always a no-no. Just squirt some extra in the carb throat and get it going, but use fresh mix in the tank...

 

[DECJ]

Well, the fuel in the tank was a little over 3 months old, so I thought it was probably still OK. But in any regard, as I mentioned, the guy at the Stihl dealer dumped the old fuel, and put some new in earlier today. Then when I got home, I made up a brand new batch of fuel and topped the tank off, so it's got all new fuel in it.

Beyond that, shouldn't I be seeing a spark at the exposed spark plug electrode when I turn over the engine?

 

[Andyshine77]

Must be the time of year, you're flooding the saw. Pull it over on choke until you hear the saw stumble, if you miss the stumble or you don't hear it after 4 strong pulls, flip the switch to the run position and it should start in 2 or 3 pulls, if not start the process over. The plug is likely just not making good contact, so you're not getting spark. No reason to use Stabil, just keep the fuel fresh, no older than three months and you will be fine.

BTW pull the plug out and pull the saw over a bunch of times to clear out the fuel in the case before you try to start her again.

 

[Guido Salvage]

You have been given good advice on how to get the saw started. My bigger concern is that you are just beginning the process of gathering wood for this year's heating season. I do not know what type of wood you may be cutting or the climate you are in, but around here the wood would not have enough time to season before it needed to be burned. "Green" or wet wood smokes, produces less heat and creates creosote that will coat your chimney/flue liner and potentially lead to a fire.

 

[DECJ]

Must be the time of year, you're flooding the saw. Pull it over on choke until you hear the saw stumble, if you miss the stumble or you don't hear it after 4 strong pulls, flip the switch to the run position and it should start in 2 or 3 pulls, if not start the process over.

What you have described is the typical technique I use on my Stihl FS-85 brush cutter and a number of other 2-stroke powered tools. However, with the MS 311, I never got the slightest indication of any stumble.

The plug is likely just not making good contact, so you're not getting spark.

You may be right. Is there a more fool-proof method I can use to ensure I am getting a spark?

BTW pull the plug out and pull the saw over a bunch of times to clear out the fuel in the case before you try to start her again.

I pulled the plug three times and thoroughly blew out the cylinder head with compressed air before trying again. Wouldn't this be just as effective as pulling the saw over to get rid of any excessive fuel build-up?

 

[DECJ]

You have been given good advice on how to get the saw started. My bigger concern is that you are just beginning the process of gathering wood for this year's heating season. I do not know what type of wood you may be cutting or the climate you are in, but around here the wood would not have enough time to season before it needed to be burned. "Green" or wet wood smokes, produces less heat and creates creosote that will coat your chimney/flue liner and potentially lead to a fire.

I live in the high desert of southeastern Utah at 7,000 feet in elevation. I have secured a BLM firewood permit for 2 cords. We are only allowed to cut Pinyon Pine or Utah Juniper (which is essentially a cedar wood). You can only cut down wood or dead trees ... nothing growing or green. With the desiccating nature of the low-humidity desert environment, the downed wood is usually very dry and burns clean & hot. And other than those folks who cut firewood to sell to others, most people who cut their own firewood do so in the August through November time frame around here.

 

[Andyshine77]

What you have described is the typical technique I use on my Stihl FS-85 brush cutter and a number of other 2-stroke powered tools. However, with the MS 311, I never got the slightest indication of any stumble.

You have a few things against you here. The saw is new, it's quiet, and the carb may need to be adjusted a little, with that said it should still start. If you miss the stumble, or it doesn't stumble, and you keep on pulling with the choke still on you will flood the saw.

You may be right. Is there a more fool-proof method I can use to ensure I am getting a spark?

Scuff a spot with sandpaper, and make sure the plug is very clean and dry.

I pulled the plug three times and thoroughly blew out the cylinder head before trying again. Wouldn't this be just as effective as pulling the saw over to get rid of any excessive fuel build-up?

No!! fuel is trapped in the bottom of the case. Try doing what I said in my last post, and happy cutting.

 

[DECJ]

I pulled the plug three times and thoroughly blew out the cylinder head with compressed air before trying again. Wouldn't this be just as effective as pulling the saw over to get rid of any excessive fuel build-up?

No!! fuel is trapped in the bottom of the case. Try doing what I said in my last post, and happy cutting.

You were right. Even after using more compressed air, I turned the saw over and pulled it over several times and a fair amount of liquid fuel came out. I then also used compressed air and got the cylinder all dried out.

You may be right. Is there a more fool-proof method I can use to ensure I am getting a spark?

Scuff a spot with sandpaper, and make sure the plug is very clean and dry.

I scuffed a spot on the outside of the cylinder head, touched the threaded portion and then the bent electrode portion of the clean & dry spark plug there while pulling the engine over and got no spark. I then removed the spark plug from the spark plug wire boot, inserted a jumper wire with an alligator clip, and then held the other end with an alligator clip very close (<.025") from the scuffed spot on the outside of the cylinder head, pulled the engine over several times and again got no spark.

What you have described is the typical technique I use on my Stihl FS-85 brush cutter and a number of other 2-stroke powered tools. However, with the MS 311, I never got the slightest indication of any stumble.

You have a few things against you here. The saw is new, it's quiet, and the carb may need to be adjusted a little, with that said it should still start. If you miss the stumble, or it doesn't stumble, and you keep on pulling with the choke still on you will flood the saw.

I actually never continued to pull the engine over with the full choke on beyond the initial attempts. Most subsequent pulls were on half-choke or just "I".


Anyway, after getting the excess fuel out of the cylinder head, cleaning/drying the spark plug, and only pulling the engine over 4 times on full-choke and then switching to half-choke (and subsequently to "I"), I never got any stumble, or any other indication that the saw was going to start.

I guess the only thing I can do at this point is to take it back to the local Stihl dealer to see if their mechanic can make sense of this.

Thanks for your help though.

Don

(BTW, I don't see what difference it would make for starting purposes, but I am at 7000 feet in elevation here while the Stihl dealer is at 4000 feet)

 

[Andyshine77]

You were right. Even after using more compressed air, I turned the saw over and pulled it over several times and a fair amount of liquid fuel came out. I then also used compressed air and got the cylinder all dried out.




I scuffed a spot on the outside of the cylinder head, touched the threaded portion and then the bent electrode portion of the clean & dry spark plug there while pulling the engine over and got no spark. I then removed the spark plug from the spark plug wire boot, inserted a jumper wire with an alligator clip, and then held the other end with an alligator clip very close (<.025") from the scuffed spot on the outside of the cylinder head, pulled the engine over several times and again got no spark.




I actually never continued to pull the engine over with the full choke on beyond the initial attempts. Most subsequent pulls were on half-choke or just "I".


Anyway, after getting the excess fuel out of the cylinder head, cleaning/drying the spark plug, and only pulling the engine over 4 times on full-choke and then switching to half-choke (and subsequently to "I"), I never got any stumble, or any other indication that the saw was going to start.

I guess the only thing I can do at this point is to take it back to the local Stihl dealer to see if their mechanic can make sense of this.

Thanks for your help though.

Don

(BTW, I don't see what difference it would make for starting purposes, but I am at 7000 feet in elevation here while the Stihl dealer is at 4000 feet)

Elevation makes a big difference. The air is thinner at 6,000 feet so the saw will run rich if it was tuned at 4,000 feet. I have to ask, did you have the switch on when testing the plug? Remember to really pull the saw over fast.

I'd try a new plug, if that doesn't work, take it to the dealer.

Best of luck.

 

[DECJ]

Elevation makes a big difference. The air is thinner at 6,000 feet so the saw will run rich if it was tuned at 4,000 feet.

Yeah, I am very aware that elevation makes a difference on the fuel-to-air mixture, but I thought the rich running condition was more of an issue for constant running rather than just starting. In the case of my Honda snowblower and generator, they have been rejetted for my altitude.

I have to ask, did you have the switch on when testing the plug?

Well, the "switch" on my MS 311 is kind of weird, in that Stihl calls it the "Master Control" lever. It is both the ignition switch as well as the choke, run, and off switch. But yes, when I tested the plug, I double checked to make sure it was in one of the three "on" positions.

Remember to really pull the saw over fast.

Yep, I was consistently pulling crazy fast.

I'd try a new plug, if that doesn't work, take it to the dealer.

I have tried a new plug twice with no difference. So, it's back to the dealer.

Best of luck.

Thanks again

 

[Andyshine77]

Yeah, I am very aware that elevation makes a difference on the fuel-to-air mixture, but I thought the rich running condition was more of an issue for constant running rather than just starting. In the case of my Honda snowblower and generator, they have been rejetted for my altitude.


Well, the "switch" on my MS 311 is kind of weird, in that Stihl calls it the "Master Control" lever. It is both the ignition switch as well as the choke, run, and off switch. But yes, when I tested the plug, I double checked to make sure it was in one of the three "on" positions.


Yep, I was consistently pulling crazy fast.


I have tried a new plug twice with no difference. So, it's back to the dealer.


Thanks again

Sounds like a bad coil or wiring issue. I'm sure it will be running soon.

 

[tilenick]

I had a similar sounding problem when I bought my MS250 (I know this saw is a lot smaller) and when I took it in, the stihl dealer said that it was speced for a bosch plug although they sold it to me new with a champion (cheaper right) plug. I bought the spec bosch plug and no more problems. Hope this helps.
Nick.

 

[Andyshine77]

I had a similar sounding problem when I bought my MS250 (I know this saw is a lot smaller) and when I took it in, the stihl dealer said that it was speced for a bosch plug although they sold it to me new with a champion (cheaper right) plug. I bought the spec bosch plug and no more problems. Hope this helps.
Nick.

I have had multiple plugs fail at the same time, all Champion, I no longer use any Champion plugs.

 

[HILLBILLYREDNEC]

Here is another thought. Take the fire screen off the muffler and then try starting the saw. Sometimes the screen can clog up and block the saw from exhaling the spent fuel and exhaust gases l,you may have plugged it from the failed starting procedure. Treying starting in the normal on position with the fire screen removed from the saw.

 

[DECJ]

I had a similar sounding problem when I bought my MS250 (I know this saw is a lot smaller) and when I took it in, the stihl dealer said that it was speced for a bosch plug although they sold it to me new with a champion (cheaper right) plug. I bought the spec bosch plug and no more problems. Hope this helps.
Nick.

Thanks Nick, however, my MS 311 came equipped with a Bosch WSR6F (R10) suppressed plug.

 

[DECJ]

It finally started !!!!!!!

Here is another thought. Take the fire screen off the muffler and then try starting the saw. Sometimes the screen can clog up and block the saw from exhaling the spent fuel and exhaust gases l,you may have plugged it from the failed starting procedure. Treying starting in the normal on position with the fire screen removed from the saw.

Based on your suggestion, I just went out and removed the fire screen. Other than being a bit discolored, it appeared to be as clean as a whistle. Nevertheless, I went ahead and gently wire brushed it with a small wire brush with stainless steel bristles and then blew it off with compressed air. As best as I could tell, the openings in the fire screen mesh were the same after doing this, so I would say it wasn't clogged up. I then blew some compressed air into the slot the fire screen slips into, but no soot or any other stuff came out of there. Then on a whim, I attempted to start up the saw without putting the screen back in, and lo and behold, it started right up and ran like a champ. I ran it for a couple of minutes, but had to stop as it's pretty late here and I am sure my neighbors wondered what the hell I was up to.

Anyway, I honestly can't say that removing the fire screen was the single item that allowed my saw to finally start up, but who knows? Anyway, I am obviously going to attempt to start my saw up several times tomorrow morning to see if I am over the hump on whatever the problem was. I will also probably add a touch of Sea Foam to the new fuel in the tank on general principle. If all goes well, I am then going to head out to finally get my winter's supply of firewood.

I'll report back, and thanks again to everyone for their help .... I really appreciate it.

Don

 

[Andyshine77]

Based on your suggestion, I just went out and removed the fire screen. Other than being a bit discolored, it appeared to be as clean as a whistle. Nevertheless, I went ahead and gently wire brushed it with a small wire brush with stainless steel bristles and then blew it off with compressed air. As best as I could tell, the openings in the fire screen mesh were the same after doing this, so I would say it wasn't clogged up. I then blew some compressed air into the slot the fire screen slips into, but no soot or any other stuff came out of there. Then on a whim, I attempted to start up the saw without putting the screen back in, and lo and behold, it started right up and ran like a champ. I ran it for a couple of minutes, but had to stop as it's pretty late here and I am sure my neighbors wondered what the hell I was up to.

Anyway, I honestly can't say that removing the fire screen was the single item that allowed my saw to finally start up, but who knows? Anyway, I am obviously going to attempt to start my saw up several times tomorrow morning to see if I am over the hump on whatever the problem was. I will also probably add a touch of Sea Foam to the new fuel in the tank on general principle. If all goes well, I am then going to head out to finally get my winter's supply of firewood.

I'll report back, and thanks again to everyone for their help .... I really appreciate it.

Don

It was flooded nothing more, it's the single most common reason inexperienced people can't start their OPE. Now quit adding stuff to your fuel, it doesn't do anything, and will likely complicate the starting issues. Just use Stihl's ultra two cycle oil, it has a stabilizer already in it plus detergents.

 

[HILLBILLYREDNEC]

Seafoam is for emergency saw use only. Clean fuel and a good 2 stroke is good enough. Yes the saw could be flooded. The saw at higher altitude definitely needs a 20% increase in exhaust outlet opening and re-tune the carb to main altitude range the saw will be used use.

 

[DALE PEPKE]

I bought one of those 311's also... Dealer tried fuel, tearing it apart numerous times, said it was fuel filter etc. it is still hard starting and out of warranty...Never again .STIHL. What a piece of junk...another boat anchor.