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New MS 201 didn't work after refueling

Started by barak, March 09, 2013, 04:25:04 PM

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barak

I took my new Stihl MS 201 yesterday to a first real job. It worked very hard cutting a big eucalyptus to small slices. The fuel tank had finished. I refueled the saw (without waiting for it to cool down). It started OK, but when I pushed the gas it turned off (it looked like the engine was choking). The problem repeated itself few times. I let the saw rest the night, and this morning it started and worked OK again, due in the begining it seemed like the engine was almost choking until it got hot enough. Am I doing something wrong, or do I have a problem with my new saw?

Ianab

Might want to get the dealer to check the carb adjustments for you.
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

thecfarm

I hardly ever touch anything that is brand new. I don't need to hear,well if you would not of done that we would of covered all the repairs. I would take it right back to them and tell them what it is doing.
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

ladylake


It needs to adjusted a little richer which the dealer should have done.  Also keep the saw in the right RPM range, lugging it down too much causes extra heat.  No letting it scream either. Steve
Timberking B20  18000  hours +  Case75xt grapple + forks+8" snow bucket + dirt bucket   770 Oliver   Lots(too many) of chainsaws, Like the Echo saws and the Stihl and Husky     W5  Case loader   1  trailers  Wright sharpener     Suffolk  setter Volvo MCT125c skid loader

Al_Smith

The 441 and the 201 just don't seem to run up to par until they get heated up from being under load .I think it's just the nature of them  but they seem to do okay once they do reach temperature .

qbilder

Think of a straw in your soda cup. Your suction pulls the fluid up into your mouth, and it happens relatively easy. Now poke a tiny hole in the side of the straw somewhere between the fluid and your lips. It's now not so easy to drink. Same logic applies to your saw.

As a motor heats up, the metals expand. It happens at a molecular level and is inevitable. It is possible that your cylinder bore warps just enough to allow blow by. While the carb is primed there is no issue, but once you run out of fuel & the carb loses it's prime, it's easier for the cylinder to blow by than it is to pull fuel into the carb.....just like with your soda straw. After it cools down & assumes it's original shape, all is well again and there is enough compression to pull a prime. Being that the engine temp is the major factor in whether the saw will prime or not, tells me that your engine is the issue. Any other issue would be a constant, not intermittent.

Two things you can do. First is check compression cold, then hot. I'd bet my dollar that your compression is much lower hot. Another thing you can do is pour a little bar oil into the spark plug hole next time this happens. Pour just enough in to seal around the rings, thus creating compression that wouldn't otherwise exist. If your saw starts in a few pulls, then you have your answer. Putting the oil in the cylinder acts like plugging the hole on your straw, and will allow for a reprime. Bar oil has a thick, sticky viscosity that won't blow by easily, but will burn away immediately once the saw fires & runs.

These mixed metal motors aren't immune to quirky little issues like warpage. One area the cheap saws reign supreme is that they utilize carbs with primer buttons. This allows a low compression motor to run because it doesn't have to pull fuel from the tank into the carb. You do it manually with a few pumps on the button. It's a genius shortcut around having to use high grade metals with strict tolerance machining, meaning the product can be significantly lower cost. But even with the high grade stuff, problems can and do occur, though less often. Stihl certainly isn't above defective metal. No manufacturer is.
         
                   

       
God bless our troops

Al_Smith

In theory perhaps but remember this guy is refering to a brand new saw made by a premeer company .This is not one of those lower priced machines made in some Pacific rim country .

Most likely what the problem is is some adjustment a dealer could make .

barak

I talked with my dealer on the phone today, he told me that there seem to be no problem at all, and there is nothing to adjust in his opinion. He told me to try to avoid finishing the gas tank before refueling, and if the problem will happen again I need to let the engine run a little bit so it will get some gas and only than to continue working.

qbilder

Quote from: Al_Smith on March 10, 2013, 02:09:48 PM
In theory perhaps but remember this guy is refering to a brand new saw made by a premeer company .This is not one of those lower priced machines made in some Pacific rim country .

Most likely what the problem is is some adjustment a dealer could make .

No saw and no saw manufacturer is immune to metal issues. It's just one of those things that can only be fixed, no prevented. Like he posted, his dealer cannot find a problem. I'd bet my dollar that a new jug will remedy the problem. A simple compression test cold vs. hot would tell it all. I know it sounds absurd and one wouldn't expect it from such a company like Stihl, but it's not a rare issue. The hot saw simply doesn't have enough compression to prime the carb. When it cools and the metal contracts, it's fine again.   
God bless our troops

qbilder

Quote from: barak on March 10, 2013, 02:28:18 PM
I talked with my dealer on the phone today, he told me that there seem to be no problem at all, and there is nothing to adjust in his opinion. He told me to try to avoid finishing the gas tank before refueling, and if the problem will happen again I need to let the engine run a little bit so it will get some gas and only than to continue working.

There's no problem cold, as he looks at it. But he's not using it to cut firewood. If it were his own saw, what would he do? It's a PIA to check fuel level while sawing so to not run out. A saw should run out of fuel, be refueled and fire right back up. You paid good money for it to do that, but it's not doing it. Keep pressuring your shop, IMO. At minimum they should swap you out under warranty for a new saw & let Stihl figure it out if the shop mechanic cannot. A carb adjustment isn't heat related. If it's out of adjustment then it's out whether cold or hot.   
God bless our troops

ladylake

 I'll still go with adjusted to lean and lugging it too much. Barak, you need to find a dealer the will ajust the carb.  One that tell you it's running fine when it isn't doesn't need your business.  Steve
Timberking B20  18000  hours +  Case75xt grapple + forks+8" snow bucket + dirt bucket   770 Oliver   Lots(too many) of chainsaws, Like the Echo saws and the Stihl and Husky     W5  Case loader   1  trailers  Wright sharpener     Suffolk  setter Volvo MCT125c skid loader

joe_indi

Barak,
Your location (Israel) explains it all!
You are located in an area which is below sea level.
This causes the saw to run leaner.
So, like everybody here is telling you, get it adjusted so that it runs richer.
And, it is not wise to run it till the tank does completely dry.Refuel well within time.
Joe

Nick Walkley

Hi Mate,

I wonder, when you ran it out of fuel did it start to rev really fast for a bit and then conked out? I this is the case I suspect you used up every last bit of fuel out of the tank and also the fuel line and carb.
If so, it often takes a couple goes to get a saw to run again. Best practice is to turn a saw off before it stops running from a lack of fuel. You will usually get a indication that the fuel is low by the saw bogging under throttle then runing fine then it will start to run really fast and peppy. This happens because the fuel is in limited supply causing the engine to run lean.
The carb requires engine pulses to lift the fuel from the tank. When restarted after running completly out of fuel it can be hard to keep going until the fuel bowl and fuel line are fully charged with fuel.

If it happens again, start the saw as you did and don't touch the throttle for 20 seconds or so. This should be enough time for the fuel system to purge all the air.
If it runs then dies without touching the throttle. Start it as though it were cold (apply choke etc...)
If it won't start at all you may have gone too far and flooded the engine.
Apply full throttle (ensure the chainbrake is on) and pull the saw over until it starts, this may take 10 or so pulls.

I hope this helps with your problem.


Nick

barak

Quote from: Nick Walkley on March 11, 2013, 05:17:42 AM
Hi Mate,

I wonder, when you ran it out of fuel did it start to rev really fast for a bit and then conked out? I this is the case I suspect you used up every last bit of fuel out of the tank and also the fuel line and carb.
Hi Nick. I did run it totaly out of fuel. Perhaps that was the problem. I did see the indication that the fuel is going to end but I didn't know that there might be a problem.
I plan to go for another work soon and I will try to work and refuel in time. I think that if the problem wont repeat itself after two or there refuels, then there realy is no problem.
Quote from: joe_indi on March 11, 2013, 04:03:37 AM
Barak,
Your location (Israel) explains it all!
You are located in an area which is below sea level.
Hi Joe.
I live in a place that is above sea level, due we are very close to Tiberias which is indeed below sea level ;)

thecfarm

barak,have you ran a chainsaw before you got this Stihl?
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

barak

Quote from: thecfarm on March 11, 2013, 03:36:23 PM
barak,have you ran a chainsaw before you got this Stihl?
Yes, I had a 2'nd hand Stihl MS 180 that made me many problems and past away after 6 months, and a Falcon CS 4580 for a short time.
I'm not a profesional user, but I bought a pro saw cause I wanted a saw that will last for a long time.
I must admit that my knowledge is very limited :-\

joe_indi

QuoteI live in a place that is above sea level, due we are very close to Tiberias which is indeed below sea level
So it is not a low altitude problem.
Until the tank ran dry the saw was running fine. And the current problem started after the dry run.Correct?
So logically, this is not a carb adjustment issue but something related to the tank running dry.
You say that it starts fine, runs fine but starts having problems(leaning out) when the engine is hot, ie after it runs for a while.
What could possibly have happened is that sediments too big to go inside the pickup body are temporarily blocking the outer mesh of the pickup body.When the saw is running the suction of fuel presses the sediments onto the mesh creating a restriction.
When the saw is idle the sediments loosen up so that the next time you start the saw, fuel flow is back to normal, until it runs for some time and the whole thing is repeated.
Remedy? Clean or replace the pickup body, and clean the fuel tank as well.
Joe

barak

well the problem didn't repeat itself.
I think the answer was in the manual guide all the time  :P:
"When the fuel tank has run completely empty... Pull the starter rope several times..."
I didn't do it  :-\

thecfarm

One thing I have always done,when I start to "hear' the saw run out of fuel,I shut it off. I don't think it is good to get all I can out of a saw that is almost out of fuel. I feel the saw REALLY starts to rev real high. I can't believe that is good for the saw either.
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

clww

My only suggestion is don't run a saw out of gas, completely. The operator's manual may describe use of the new saw in regards to a break-in period, too.
Best wishes to you! ;)
Many Stihl Saws-16"-60"
"Go Ask The Other Master Chief"
18-Wheeler Driver

Ianab

QuoteI feel the saw REALLY starts to rev real high. I can't believe that is good for the saw either.

It's not, because the saw is running very lean at that stage as it starves of fuel, and that's never a good thing. If you stop as soon as you hear that sound there should still be enough gas in the carb and fuel lines to restart the saw again (easily)

If you are felling trees, especially larger ones, check the gas before you start. You don't want to run out 90% of the way though  :-\ If you are limbing or bucking and have to stop 1/2 way though a cut for gas, no big deal.

Ian
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

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