N9WOS
ArboristSite Lurker
AKA vapor lock causing customer returns of perfectly good saws.
I have seen people at this forum posting with the same problems from time to time so I am posting this here so that people are aware of the most likely cause of that problem. Because I have almost never heard it mentioned when someone complains about the same basic problem. Except on rare occasion, like the earlier post. Thanks ECHOMAN8 !!!
The problem of the saw starting and running fine when cold, and after it heats up, you can shut it off for a few minutes and then it won’t start.
I have seen numerous shopping review sites that list people complaining about different saws not wanting to start when hot. And how they take them back for a refund. And even in this website, I have seen people list that same problem, and someone tells them to take it back and get a different one. In all likelihood, the saw is most likely perfectly fine. The saw isn’t defective. It is just a result of the fact that saws use a non pressurized fuel system, (ie) carburetor
In some parts of the country it is worse than in others. Some saw models are a little bit more sensitive to it than others. It is aggravated by temperature. But the primary cause is the GAS that they are using.
Living in Indiana, and using chainsaws for over 16 years (over half my life) to keep my butt warm. I have noticed a drastic change in the gas formulation around 2002 to 2002 It has only gotten worse since then. The biggest thing that it affected was my vehicles. I have drove carbureted vehicles since for the entire time. Around the2000, I was left on the side of the road with vapor lock more times than I cared to count until I figured out what was going on and took corrective measures.
The basis of the problem. Back years ago, they had to formulate gas so that the vapor pressure was low enough that it wouldn’t violently boil away at normal engine temps. A little bubbling was fine, but not a total fizz out. That was because the pump and the carb was on/ and or/ attached to the engine in question. You fizz in the pump and it don’t pump no more. Car runs out of gas, with a full tank of gas. You get fizz in the carb, then you get surging and other freaky things.
But as time progressed, more cars went to fuel injection. With fuel injection, vapor pressure isn’t a problem. The tank is cold, where the pump is. The lines going from the tank to the engine and back is all pressurized. Even higher vapor pressure fuel at 50 to 100PSI will not boil at engine temps. So vapor lock isn’t a problem. And high VP aids in cold engine, and cold weather starting.
So, around 2000 or so, they evidently figured that there was so few carbureted vehicles on the road, that it no longer justified restraining the formulation to avoid affecting them. So they thinned out the gas to more closely match the ideal fuel for fuel injected cars. (ie) Higher vapor pressure lower boiling point fuel.
It caused my old 1 ton van to take fits during hot weather until I figured out that even with a brand new fuel pump, the pump won’t work when it got hot. Never had a vapor lock problem before 2000 So I changed to a electromechanical pump that I located along the frame. Even with it far away from the engine heat I can still hear it chattering once in a while sitting in traffic, when it road heat gets it hot enough that the fuel in it starts vaporizing.
So I was not surprised when I started noticing the same tell tail signs with the chainsaws I have.
The three chainsaws I have and the ones that belong to other people that I use once in a while have all showed problems. It is not brand specific. Some are worse than other but all have showed signs.
When it’s a hot day and I shut the saw down for a few minutes and go back to it. When I start it and it runs for a few seconds and then stalls and is hard, or impossible to restart. I don’t get mad at the saw. I know it isn’t the saws fault. On real hot days I try not to shut off the chainsaw. I just leave it idling until I get done moving brush and then pick it up and continue about my business. That avoids vapor locking.
The ones I own are a Homelite 330, 240, and a 23AV. The 23AV and 240 usualy show no problems when you leave them running. When it’s really hot the 330 will sometimes start acting up under really heavy load because the carb is sitting right on the engine. I never have had any problem with the 330 and 240 before 2000.
The other people’s saws I use are a stihl 028 and a slightly bigger one that I can’t remember the model number of right now. The 028 is by for the crankiest one that I have put up with. It USUALLY doesn’t have a problem with starting while hot, but it has a problem when running on hot days. When you get a batch of real light gas it will start chugging surging, and stalling out under sustained cutting conditions in even moderately warm weather. With good gas it will usually do ok under most hot weather conditions. The larger stihl will run fine is you run it long enough to warm up the gas tank and everything. That builds up the pressure in the fuel tank, and the rest of the fuel system and helps stop it from boiling in carb. But heaven forbid if you try to take a cold saw, and start it up to cut two or three large cuts, then shut it back off for a few minutes. You might as well not even try to start it and go to the fridge to get a pepsi or something. Just sit back and relax while the engine cools down because there is no way on god’s green earth that you are going to get it started.
For the stihl fans out there, yes the 028 cooling fins are clean as a bell when it’s doing that. It’s not an abnormal heat buildup issue. I have had that saw apart more times than I care to count.
Various Poulan and mcculloch, same general list as above.
There isn’t a saw that I have used for a good hot day (95F +) of heavy work that I haven’t had problem with restarting if the saw if the saw was shut off fully hot.
I know the homelite 23AV is a light duty saw, but I have worked the heck out of it in the 7 years I have owned it. I would say it’s personally cut over 200 rick of wood went through several bars and more chains than I can count.. And I have pretty much learnt how to get it out of vapor lock reliably. Pull (run… sputter die) choke, pull (gurgle) unchoke (run sputter die) choke, pull (gurgle) unchoke (run sputter die) repeat until it runs long enough for you to milk the throttle. Try to get the revs up to pull cold air and fuel into the carb. Once the car cools down, then it will level out and you can proceed to cut.
That system pretty much works with the 330, 240, and the other brands of saws that I have to use once in a while. All except for the big stihl when it is in a bad mood.
If I leave gas sitting without a lid on the can/vent open, which allows the light components of the gas to evaporate over a month or so, then the gas usually doesn’t show any problem with vapor locking.
Gas that is gotten during the winter months usually causes the saws to be more cranky when it’s used in hot weather.
Some gas stations seem to have worse gas than others at random times. It’s a gamble. If I get a five gallon can that does good when I mix a gallon of it, then I usually sit back the other four gallons for future saw use.
The 23AV is in the same line of post buyout homelite saws that include the 33, 42, and 46 CC saws. Same general construction and shares parts with them. I know they are not the best in the world, and they share no real design similarities to the pre buyout saws, but in defense of my old 23AV that has served me faithfully, I have to say, they are not worthless junk.
It has held up well running along the 330, and 240. The only thing I have had to do to it is remove the worthless spark arrestor that started to clog after about three months of heavy use. And a vibrations isolator spring that has went from time to time.
So, when I see people returning what I know to be a perfectly good saw because of a problem that is caused not by the saw it’s self, but the gas that is sold in the area, A problem that I am all to familiar with, I decided to write this post to try and give everyone an idea what the actual problem may be.
The gas supply isn’t as consistent as it use to be, and it will cause problems from time to time. Don’t be so quick to denounce a piece of equipment. Tell them to try a better grade of gas before hauling a perfectly good piece of equipment back in for a refund.
Or, if they can’t get better gas, at least tell them why it’s doing it, so they can better understand the problem and try to change there usage habits to avoid the problem in the first place.
Just because you don’t have problems with vapor locking where you live doesn’t mean that someone else won’t where they live. There is hundreds of gas formulations around the country. They change depending on winter, summer or fall. Some formulations will cause problems, other’s won’t.
And if you have problems with a piece of equipment acting up, don’t be so quick to cuss it. Sit back and think it through.
Returning good stuff waste time, irritates retailers, causes companies to get a bad name when they don’t deserve it, and costs everyone money in general.
The same thing goes for gas gumming up. Different formulations will break down quicker. You may be able to leave the summer gas sitting for four years and it’s still usable, but winter gas may turn to sludge in under a year.
Just keep that in mind when you hear someone complaining about equipment problems. Even if it’s a brand of equipment that you are not that fond of. It may be the gas that is the problem.
Keep that chain spinning! :greenchainsaw:
I have seen people at this forum posting with the same problems from time to time so I am posting this here so that people are aware of the most likely cause of that problem. Because I have almost never heard it mentioned when someone complains about the same basic problem. Except on rare occasion, like the earlier post. Thanks ECHOMAN8 !!!
The problem of the saw starting and running fine when cold, and after it heats up, you can shut it off for a few minutes and then it won’t start.
I have seen numerous shopping review sites that list people complaining about different saws not wanting to start when hot. And how they take them back for a refund. And even in this website, I have seen people list that same problem, and someone tells them to take it back and get a different one. In all likelihood, the saw is most likely perfectly fine. The saw isn’t defective. It is just a result of the fact that saws use a non pressurized fuel system, (ie) carburetor
In some parts of the country it is worse than in others. Some saw models are a little bit more sensitive to it than others. It is aggravated by temperature. But the primary cause is the GAS that they are using.
Living in Indiana, and using chainsaws for over 16 years (over half my life) to keep my butt warm. I have noticed a drastic change in the gas formulation around 2002 to 2002 It has only gotten worse since then. The biggest thing that it affected was my vehicles. I have drove carbureted vehicles since for the entire time. Around the2000, I was left on the side of the road with vapor lock more times than I cared to count until I figured out what was going on and took corrective measures.
The basis of the problem. Back years ago, they had to formulate gas so that the vapor pressure was low enough that it wouldn’t violently boil away at normal engine temps. A little bubbling was fine, but not a total fizz out. That was because the pump and the carb was on/ and or/ attached to the engine in question. You fizz in the pump and it don’t pump no more. Car runs out of gas, with a full tank of gas. You get fizz in the carb, then you get surging and other freaky things.
But as time progressed, more cars went to fuel injection. With fuel injection, vapor pressure isn’t a problem. The tank is cold, where the pump is. The lines going from the tank to the engine and back is all pressurized. Even higher vapor pressure fuel at 50 to 100PSI will not boil at engine temps. So vapor lock isn’t a problem. And high VP aids in cold engine, and cold weather starting.
So, around 2000 or so, they evidently figured that there was so few carbureted vehicles on the road, that it no longer justified restraining the formulation to avoid affecting them. So they thinned out the gas to more closely match the ideal fuel for fuel injected cars. (ie) Higher vapor pressure lower boiling point fuel.
It caused my old 1 ton van to take fits during hot weather until I figured out that even with a brand new fuel pump, the pump won’t work when it got hot. Never had a vapor lock problem before 2000 So I changed to a electromechanical pump that I located along the frame. Even with it far away from the engine heat I can still hear it chattering once in a while sitting in traffic, when it road heat gets it hot enough that the fuel in it starts vaporizing.
So I was not surprised when I started noticing the same tell tail signs with the chainsaws I have.
The three chainsaws I have and the ones that belong to other people that I use once in a while have all showed problems. It is not brand specific. Some are worse than other but all have showed signs.
When it’s a hot day and I shut the saw down for a few minutes and go back to it. When I start it and it runs for a few seconds and then stalls and is hard, or impossible to restart. I don’t get mad at the saw. I know it isn’t the saws fault. On real hot days I try not to shut off the chainsaw. I just leave it idling until I get done moving brush and then pick it up and continue about my business. That avoids vapor locking.
The ones I own are a Homelite 330, 240, and a 23AV. The 23AV and 240 usualy show no problems when you leave them running. When it’s really hot the 330 will sometimes start acting up under really heavy load because the carb is sitting right on the engine. I never have had any problem with the 330 and 240 before 2000.
The other people’s saws I use are a stihl 028 and a slightly bigger one that I can’t remember the model number of right now. The 028 is by for the crankiest one that I have put up with. It USUALLY doesn’t have a problem with starting while hot, but it has a problem when running on hot days. When you get a batch of real light gas it will start chugging surging, and stalling out under sustained cutting conditions in even moderately warm weather. With good gas it will usually do ok under most hot weather conditions. The larger stihl will run fine is you run it long enough to warm up the gas tank and everything. That builds up the pressure in the fuel tank, and the rest of the fuel system and helps stop it from boiling in carb. But heaven forbid if you try to take a cold saw, and start it up to cut two or three large cuts, then shut it back off for a few minutes. You might as well not even try to start it and go to the fridge to get a pepsi or something. Just sit back and relax while the engine cools down because there is no way on god’s green earth that you are going to get it started.
For the stihl fans out there, yes the 028 cooling fins are clean as a bell when it’s doing that. It’s not an abnormal heat buildup issue. I have had that saw apart more times than I care to count.
Various Poulan and mcculloch, same general list as above.
There isn’t a saw that I have used for a good hot day (95F +) of heavy work that I haven’t had problem with restarting if the saw if the saw was shut off fully hot.
I know the homelite 23AV is a light duty saw, but I have worked the heck out of it in the 7 years I have owned it. I would say it’s personally cut over 200 rick of wood went through several bars and more chains than I can count.. And I have pretty much learnt how to get it out of vapor lock reliably. Pull (run… sputter die) choke, pull (gurgle) unchoke (run sputter die) choke, pull (gurgle) unchoke (run sputter die) repeat until it runs long enough for you to milk the throttle. Try to get the revs up to pull cold air and fuel into the carb. Once the car cools down, then it will level out and you can proceed to cut.
That system pretty much works with the 330, 240, and the other brands of saws that I have to use once in a while. All except for the big stihl when it is in a bad mood.
If I leave gas sitting without a lid on the can/vent open, which allows the light components of the gas to evaporate over a month or so, then the gas usually doesn’t show any problem with vapor locking.
Gas that is gotten during the winter months usually causes the saws to be more cranky when it’s used in hot weather.
Some gas stations seem to have worse gas than others at random times. It’s a gamble. If I get a five gallon can that does good when I mix a gallon of it, then I usually sit back the other four gallons for future saw use.
The 23AV is in the same line of post buyout homelite saws that include the 33, 42, and 46 CC saws. Same general construction and shares parts with them. I know they are not the best in the world, and they share no real design similarities to the pre buyout saws, but in defense of my old 23AV that has served me faithfully, I have to say, they are not worthless junk.
It has held up well running along the 330, and 240. The only thing I have had to do to it is remove the worthless spark arrestor that started to clog after about three months of heavy use. And a vibrations isolator spring that has went from time to time.
So, when I see people returning what I know to be a perfectly good saw because of a problem that is caused not by the saw it’s self, but the gas that is sold in the area, A problem that I am all to familiar with, I decided to write this post to try and give everyone an idea what the actual problem may be.
The gas supply isn’t as consistent as it use to be, and it will cause problems from time to time. Don’t be so quick to denounce a piece of equipment. Tell them to try a better grade of gas before hauling a perfectly good piece of equipment back in for a refund.
Or, if they can’t get better gas, at least tell them why it’s doing it, so they can better understand the problem and try to change there usage habits to avoid the problem in the first place.
Just because you don’t have problems with vapor locking where you live doesn’t mean that someone else won’t where they live. There is hundreds of gas formulations around the country. They change depending on winter, summer or fall. Some formulations will cause problems, other’s won’t.
And if you have problems with a piece of equipment acting up, don’t be so quick to cuss it. Sit back and think it through.
Returning good stuff waste time, irritates retailers, causes companies to get a bad name when they don’t deserve it, and costs everyone money in general.
The same thing goes for gas gumming up. Different formulations will break down quicker. You may be able to leave the summer gas sitting for four years and it’s still usable, but winter gas may turn to sludge in under a year.
Just keep that in mind when you hear someone complaining about equipment problems. Even if it’s a brand of equipment that you are not that fond of. It may be the gas that is the problem.
Keep that chain spinning! :greenchainsaw:
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