So, you’ve been diligent about starting your generator on a regular basis, you’ve kept fuel stabilizer in the tank, and then one cold winter day you go out to fire up your generator and it just won’t start. You might be wondering what you did wrong so let me take a minute and explain what might be going on.
During the 8 plus years that our family lived off the grid our only source of electricity was a generator. Starting certain types of generators in the winter can be a real bear at times. Even our nice Honda EU2000i was often difficult to start during really cold temperatures.
We can’t predict when we’ll need to rely on our emergency generator which is why it’s so important that you read and understand the information in this article.
Why Your Generator Won’t Start When it’s Cold
When the temperature is low, the oil in your generator is going to be cold as well. When oil is cold, it is much thicker than when it is warm. This can cause three problems for you when you’re trying to start a generator on a cold winter morning.
The first is that because the oil is cold and thick, it’s going to be more difficult to pull the cord to start the engine. If it’s normally quite easy to pull the cord, when the temperatures are really low, it’s going to be more difficult because the oil is much thicker.
Cold oil also makes a generator with an electric starter more difficult to start. Cold batteries don’t have as much cranking power. Also keep in mind that just like it’s more difficult for you to pull the cord, the starter on your electric start generator is going to have to work that much harder to crank the engine over. In some cases, you might run the battery down to a level that is so low that it won’t turn the engine over at all.
The third problem that you might experience may seem quite strange to you but keep reading and it will become perfectly clear. Many generators have what are called, “low oil shutdown sensors” on them. These sensors are designed to automatically turn the engine on your generator off if it doesn’t detect that there is enough oil in your generator. This is a GOOD thing because it may help prevent costly engine damage if you don’t have enough oil in your generator’s engine.
Unfortunately, this feature can be very frustrating when the temperatures are cold. Here’s what we experienced with our little Honda generator in sub-freezing temperatures. The generator would start like normal but it might only run for about 10 seconds and then then the low oil shutdown indicator light would illuminate and the generator would automatically shut down.
We were certain that the engine had enough oil in it but the failsafe still triggered. After waiting a few seconds, we would try starting the engine again. If we were lucky, the engine might run for around 15 or so seconds this time before it shut down. Depending on exactly how cold it was, we might have to repeat this process several times. Each time the engine would stay running a little longer than the time before. Eventually, the engine would start and continue running.
Now, keep in mind that we’re not small engine mechanics but since this only happens to us when the temperatures are low, I think it’s fair to believe that since the engine oil is cold and thick, the oil in the generator’s engine isn’t flowing like it would when it is warm. We believe that this is what causes the the low oil shut down sensor to shut the engine off even though the engine isn’t actually low on oil.
Furthermore, this leads us to believe that each time the engine starts and runs for a few seconds the oil is slowly warming up. As it slowly becomes warmer and warmer, it is able to flow more easily. When it flows well enough, the low oil shutdown sensor no longer thinks that there isn’t oil in the engine and consequently, it doesn’t shut the engine down.
I should point out that we’ve owned three of these generators over about 13 years and the reason we kept buying them is because we really like them. We’re actually still using two of the three. My son and daughter-in-law are using one right now as their only source of electricity in our little off-the-grid cabin as a matter of fact.
I would like to point out that we experienced the same symptom on all three generators during cold weather conditions. The solution for us was to consult the owner’s manual to find out what viscosity of oil we should be running in the engine for the current temperatures. The manual said that when the temperatures fell and stayed below a certain temperature, we could use 5W-30 oil which is what we did.
If you choose to change to a lighter weight oil during the winter, be sure to change back to oil of the appropriate viscosity when the temperatures rise to prevent unnecessary engine wear.
Using the proper viscosity oil and following the manufacturer’s instructions for cold weather starts is a much better alternative than restarting the engine over and over until the oil warms up enough for the engine to stay running. If the oil isn’t flowing well enough to keep the sensor from shutting the generator down, it’s not flowing well enough to properly lubricate the engine.
With that in mind, if you find yourself in an emergency and you’re having a difficult time starting your generator because it’s really cold outside. Doing what we did may help you get it started and keep it running. But be forewarned, it very well could extra wear and tear on your generator’s engine.
When we switched to this lower viscosity oil, the problem would sometimes still rear its ugly head to some degree but the generators were much easier to start. So the moral of this story is to read your instruction manual. You just might find that they will recommend that you use oil with a lower viscosity during extremely cold temperatures.
Again, keeping in mind that I’m not a mechanic, it stands to reason that oil that will flow at lower temperatures will do a better job of properly lubricating your generator’s engine on cold days. So, you’ll get a two-fold benefit for making sure that you have the proper oil in your generator during the winter. First, it should be easier to start and second, it may reduce the wear that your engine experiences during cold morning starts.
Read the Manual BEFORE Using Your Generator
I know, I know, reading instruction manuals isn’t much fun but they do contain very important operating and safety information. You might find that the manual for the engine on your generator has special instructions for starting a cold engine and/or running your generator in cold temperatures. So, for your own sanity and in the interest of taking good care of your generator, please read the manual.
More Generator Help Articles
If you’re interested in learning more about generators or you need help with yours click here to see my full list of articles about generators.
Don’t Forget to Read the Comments Below for More Insight
Several people have offered their advice in the comment section below for what they do to help with the problem of starting a cold generator. You might want to read their comments and if you have any tips of your own, please feel free to leave a comment as well.