How to Winterize a Generator – Fuel Logic

October 18, 2023

Portable generators are a backup for a sudden power outage or when no power supply is nearby. Hence, they are the most important electrical gadgets for businesses such as construction, farming, and grocery stores.

However, with a sudden drop in temperature during the winter, these generators need to be stored properly. Otherwise, the diesel fuel in them tends to thicken, causing the engine to get ruined if not managed properly. If your generator breaks down, it will increase your cost a lot and harm the profitability business in the long run.

This article will save you from wrecking your machine and give you all the information about winterizing a generator.

how to winterize a generator

What Happens If You Don't Winterize a Generator?

If your portable generator is not winterized beforehand, then the most common possibilities are:

Corrosion and Engine Breakdown

Its engine will break down due to any moisture that causes corrosion on the metal pipes of the generator.

Diesel Gelling

Due to the freezing temperature, the paraffin in the diesel will make it turn into a gel-like consistency, causing parts of the engine to rub against each other and get ruined. It is also known as diesel gelling.

Slow Start and Engine Issues

Non-winterized generators have a chance of taking a long time to warm up and start because the engine will not run smoothly due to diesel gelling.

How to Winterize a Generator?

Many steps can be taken to winterize a generator for the cold weather:

Cold Flow Improver

To improve the flow of your diesel in winter, you can use something called the cold flow improver. It prevents the diesel from gelling. However, avoid overuse as it can affect the performance of the fuel.

Preventing Corrosion

Drain your engine's filters and water separators so there is not even a drop of water inside the generator, as it can corrode the metal in its pipes and hinder flow.

Diesel Fuel Options for Cold Weather

There are now diesel fuel additives available for cold temperatures. They can handle cold weather without forming a gel, but be sure to perform regular checks on this diesel for any of the common signs of diesel spoiling.

Regular Maintenance Checks

Regularly check for issues like radiator leaks, cracked belts, or plugged hoses while storing the generator. Also, check if all nuts and screws are in place so that there is no compromise in the workability of the generator when you turn it back on.

Protecting the Electrical System

The electrical system, like the electrical outlets of the generator, can be destroyed due to water and snow, so avoid contact with any moisture by keeping the machine covered.

Battery Care in Cold Temperatures

Ensure disconnecting battery cables, as they can get drained if they remain connected. Also, when the outside temperature decreases, the battery starts to drain. Therefore, remove and store the battery in a warm environment.

Preventing Corrosion

Grease all the outer and inner metal parts of your generator while storing. Otherwise, they can corrode and catch rust, severely damaging the performance of generators. Therefore, even after greasing, keep them in a cool and dry place.

Battery Maintenance

It is important to regularly check the battery to see whether it needs to be charged, as it can drain due to being stored in low temperatures. Also, ensure no damage has been caused; otherwise, you must change it on time.

Fuel Stabiliser for Unattended Operation

A fuel stabilizer can be added to the generator's tank if it is possible to leave it unattended for a few days. It will keep the internal components of the generator lubricated.

Equipment That Helps in Preparing Your Portable/Standby Generator for Winter

To winterize a generator, you need the following equipment:

Engine Block Heaters 

It warms the oil before starting the engine. There are three types of heaters:

  • A hydronic cooler heater - keeps the whole engine warm.
  • A block heater - it helps the coolant in the engine warm enough so it travels through the machine easily.
  • Control panel box heaters - these stop the control panel equipment from being damaged because of preventing condensation and buildup.

Note: This is a very effective method; however, it is important to check the compatibility of the heater with your generator.

Battery Warmers 

These are used in winter to keep the battery warm. It helps in reducing pressure on the battery and prolongs its life. They are placed underneath the battery and automatically turn on when the battery drops below a certain number.

Snow Hood Kits 

These are used in winter to cover the generator in a way that keeps the snow away from the generator. It keeps it safe from snow falling on the pipes and prevents corrosion due to no moisture contact.


They help to control the internal and external airflow of the engine. They ensure that the machine works properly.

How to Run Your Portable Generator in Winter?

To make your engine run smoothly in winter, turn it on for 10-15 minutes before plugging it into a load. In this way, the fuel warms up and travels through all the pipes, easing up the diesel flow. It happens if you properly winterize a generator before the winter season.

It is necessary to give it some time. Otherwise, if you turn it on and right away connect it to a load, then the engine will be destroyed as diesel gel will not be able to move through pipes causing the machine to overwork and probably stop working right away.

If you run out of diesel, you can use our fuel delivery service to get it delivered right to your doorstep from our nationwide delivery service.

Storage of Generator in Winters

Portable or standby heaters are meant to come in use when there is no power supply or a power outage that can happen for several reasons.

It is highly required by businesses to use it when it is needed urgently. Hence, the proper winterization of standby generators is necessary for them to be available at times of need. The following steps should be followed to avoid such issues:

1. The generators should be stored at a safe distance from snow to avoid any moisture getting in contact with our machine

2. Cold weather causes the battery to drain. Therefore, keeping a battery warmer would ensure that it will be warmed up every time the temperature drops below an average of 40 degrees.

3. Use a block heater to heat your engine oil before turning it on so it gets to the proper temperature before going through pipes.

4. You need to add a cold flow improver to your generator as it prevents your diesel fuel from gelling up. It helps ensure a smooth flow of diesel through the pipes. 

Note: Always research what works best for the engine and what is recommended for it to get the most out of your machine.

Meanwhile, if you’re interested in refueling your generator, you can use our generator refueling service to refill your generators at your doorstep.

Protect Your Investment: Winter Maintenance for Your Generator

When we get equipment for our businesses, it is very important to remember that it needs proper attention and care. Generator winterization helps us take proper care of it so it can be used whenever needed. Similarly, a standby or portable generator is a machine that is instantly required if there is a power outage or any emergency. 

It would be best if you researched the compatibility of your generator with all the methods mentioned in this article. Read the instruction manual of your machine to get to know which techniques of winterization work best for your generator.

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