My intention here is try to give you a few pointers and suggestions on the care and feeding of your generator power plant. As with all these articles on this site, I'm assuming that you are doing your homework, reading your owner's manual, and looking for underlying principles and ideas.

You, as an independent thinker should read what I've written and apply what makes sense to you. We've been doing this for quite a while now and our experience, I hope, will be helpful. I've managed to get 2500 hours out of most of the little generators I've used over the years, which is much more than I've been told you can expect. I think the biggest reason for our success has been the use of synthetic oil.

When you buy a generator system, look for an hour meter. When you have a way to monitor generator run time, you can establish a sensible maintenance schedule. If your generator is for standby use, and only runs for a half hour every week or so, then check it monthly or quarterly. If you use it daily then take the time to look it over often and watch the use of oil and fuel. You'll get to where you can anticipate when things aren't right long before a failure.

Good maintenance is essential for long life. "Grease is cheaper than pieces" That's what my pappy taught me, and he was right!

OIL

.... for Gasoline Powered Generators

Gasoline is a light fuel that burns fast, hot and dry. High RPM generators (typically 3600 RPM, or 60 revolutions per second) are often air cooled and sometimes have hot spots along the cylinder due to uneven air flow. Using air for cooling can mean wide variations in temperature throughout the engine, and generally higher operating temperatures than a water cooled system. All of this puts greater stress on lubricating oils.

Here in the US, 30W non-synthetic oil is recommended by most generator manufacturers for summer use. I highly advise you to use synthetic oil whenever possible. Multi-viscosity oils are a must in winter, especially with below freezing temperatures. I use on my air cooled generators 0W-30W for January (Our coldest month), 5W-30W for Nov-Dec and Feb-Mar. 30W the rest of the year. Straight 30W oil becomes too thick to lubricate properly at very low temperatures. Multi-viscosity oils remain thin enough to flow properly in the cold, but still maintain the protection of a thicker oil at high temperatures.

I notice now that Briggs and Stratton is now recommending synthetic oil in their newer generators.

The smaller air cooled generators often have no oil filter at all! In this case, changing oil every 100 hours is important. With synthetic, so long as the oil is clean you can push it a little longer. Read your manual and don't forget to keep your oil clean and change it often. Most of these small engines hold only a quart or so of oil.

I've noticed that several of the generators I've used that are built in China dirty the oil right away. I'm not sure what the reason for this might be, except perhaps a ring seating wear-in process. Whatever the cause, change the oil often when you see it turn dark. The black coloring is caused by carbon and other abrasives that are suspension in the oil. Keep the oil clean and as clear as you can.

If you are going to have a few gallons of gasoline around for an emergency, use a fuel stabilizer so that it will last longer in storage. An emergency is NOT the time to find out that your fuel is unusable.

.... for Diesel Powered Generators

Diesel fuel burns slower, at a lower temperature. Diesel fuel is essentially an oil and offers great lubrication for the cylinders as it burns. The less violent, but very powerful properties of diesel as a fuel make it the preferred fuel for generators that need to last a long time, and run economically.

As with gasoline generators good clean oil is essential to long generator life. The characteristics of diesel as a fuel combined with larger bearing journals, larger oil capacities, and good oil filtering in most cases, allow you to follow manufacturers guidelines and in many cases you can get by without synthetic oils. I intend to keep using synthetic oils, but an oil change when the crankcase hold 18-22 quarts is a much bigger deal with a large diesel. The little air cooled generators sometimes only hold a quart of oil, so there's a big difference in the cost of an oil change when dealing with a larger diesel generator set.

In the case of these larger generators the oil change interval is 1,000 hours instead of 100 hours, so changing oil occurs much less frequently. Most small generators will not even last a thousand hours without tender care and some good luck!

I cannot recommend highly enough the use of a Frantz oil filter (http://www.wefilterit.com). I make no commission on this, I just believe that if your generator is a diesel with a long design life you need this filter system! It flat works!

Diesel fuel stores well, but additives are available to keep it flowing at low temperatures. Depending on your climate, this could be critical.

Replace Those Filters

I've been amazed over the years at the garbage that gradually accumulates in the bottom of my gas cans, and in my fuel filters. Water is also a big issue that is hard to get away from. Good filters, replaced periodically, are essential to long life.

Dirt and dust get into everything. Dust is like sandpaper and can quickly ruin any engine. Keep filters in place, and replace them before they get really awful..

Keep your Generator Clean

Oil drips and other issues are easy to spot and take care of when the engine is nice and clean. Less dust around the engine means the air could be a little cleaner for the engine. Visual inspection can guarantee that hoses and belts are in good condition. Frequent checks can keep wasps and other nuisances from nesting in your equipment.

In an emergency you want everything ready to go. Neglect sets the stage for problems. So get into a habit of making sure everything is ready to go.

Spares

You can overdo preparation in some areas so use good judgment here, but you should have a spare oil filter, air filter, fuel filter, belts, and brushes if your generator uses them. If you need spark plugs, have a couple spares around. The purpose of preparation is to buy yourself time and to reduce the odds of difficulty. So prepare!

Generator Brushes

When replacing a brush set on your generator you should have burnishing tool to clean and smooth the armature so the new brushes will last a while. Otherwise the uneven and pitted surface will eat the new brush away in only a few hours. If your generator uses brushes and is in constant daily use you will most likely wear out your brushes! You want to replace them before they completely wear out and arc over and damage your generator's armature. This will save you money and you'll get more life and more generated power for your dollar. Once those copper contacts those brushes are sliding on are damaged, it's very hard to get long life out of your replacement brushes.

Some brush sets can be flipped over (swapping wire contacts, of course) and life can be extended until you get a replacement if you spot excess wear in time. But monthly visual inspection is required to catch this problem on heavily used generators. Usually your OK for 3-4 months use, but then you should start your monthly brush checks. This is usually a pretty simple thing to do, your owner's manual should show you what you need to know. It's interesting that in a typical dual brush set, one brush wears a lot faster than the other. (Which is why, in a jam, flipping the brush holder over works as a temporary solution if you can see that you need to get a replacement brush set.)

It is better to have a spare set around then rely on the brush set flipping option. Your generator might not be one that would allow you that option! Avoiding an emergency is the smarter tactic, but it might be something you need to know someday, so now you know...

If you're totally dependent on a generator, an inexpensive spare generator can get you by until you get your primary generator set repaired.

If you're using a diesel generator as your primary source of power, a gas backup generator might be a good idea in case diesel fuel is temporarily hard to come by.

Finally

Good maintenance is mostly common sense. The more you use a piece of equipment and rely on it, the more you need to take care of it. A diesel gen set that is rarely used might not need a lot of care. In fact you can get lulled into a sense of false security. Take care of your generator so it's ready to put into action. Start it weekly or at least monthly just to be sure that it's running well and that the battery is charged and ready. Run the generator for an hour or so. You want it to come up to operating temperature and charge your starting battery. A trickle charger is also a good option.