Generator exercise for long term storage

1297 Views 43 Replies 21 Participants Last post by squeekk, 3 d ago

Corpus

Discussion Starter · 15 d ago (Edited)

A couple Genny LTS questions:

First, the in-laws are giving us a new-never started inverter/generator. It sat in their shed (boxed) for a couple of years until they decided to go with a larger standby genny. It is unmolested by mice or bugs. I have a larger genny that I use a few times a year for outages but I’d like to keep this one pristine as a backup.
My question is, if it’s never been started does it need periodic regular exercise?
I assume some generators sit on the shelf for awhile before being sold so I think it must be ok but I need to know for sure.
IOW: Am I better off storing it as is for possibly years or do I need to gas it up and exercise it every few months for years until it’s needed?
My preference would be to store it unused and keep some extra maintenance supplies on hand like filters, plugs, wires, battery etc.

Second, I confess I don’t completely understand the reasoning for periodic exercise of generators so hopefully someone can help me wrap my head around it.

Thanks.

ETA: It is a name brand either Honda or Yamaha Inverter/Generator in the 3000 watt range in case that makes a difference in storage strategy. I know it cost around $2500 to $3000 so I’d like to be sure I do it right.

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irv818

· #2 · 15 d ago

Apparently, the answer is yes, you should exercise it periodically.
How periodically? Everybody seems to be guessing.
I would run it maybe quarterly - with a load.
Then carefully drain the gas from the tank and carb.
And of course only use ethanol-free gas.

Reactions: 5

thess02

· #3 · 15 d ago

Generators are emergency backup power. You should exercise them to make sure, or at least have confidence they'll work in an emergency when needed. They aren't appliances. Read the owner's manual first. You may need to breakin the engine. Change oil annually or at the recommended hour intervals. Follow the owner's manual for the required maintenance. I exercise my diesel generator weekly. It's my primary. The 2 gasoline fueled generators are exercised monthly. Run them under a load too...50% load is good.

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Aberro

· #4 · 15 d ago

For what it’s worth, I have a 5k watt generator from 2004 I got after hurricane Ivan. It ran for many hours then. (Broken in)

I still have it plus other smaller ones now that I know a refrigerator and freezer can be ran (not together) with a 1k watt .

I always drain the tank, empty the carb and run till quits, and drain the oil before storage. It sat for 10 years in a dry garage.

I got it out and decided to sell it since I have several. Added gas and oil, it started on the first pull.

Now if it was my only generator, I might think differently, but this is a true story. YMMV.

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Bluwolf

· #5 · 15 d ago

I agree with everything above. You should run them periodically. As irv818 said, how often is up for discussion and you will get almost as many answers as people you will ask. I have a reminder on my computer to run mine every 6 weeks. But if I get busy with other stuff I don't lose sleep if it goes a little longer. The point is to do it somewhat regularly.

I've heard and read many stories of people thinking that leaving it new in the box was a good idea, only to find out when they needed it, it didn't work for one reason or another. It may look pristine on the outside but you don't know what's going on inside. It's good to get some oil thrown around in there, up on the cylinder wall, on all the moving parts, etc. As Thess02 said, change the oil once a year or at the regular maintenance intervals, whichever is less time.

I'm betting there is a break-in period. My two gens were 5 hours with regular oil. I changed the oil after 2 hours just in case there was metal floating around. Then another 3 hours on regular oil. Then switched to a good synthetic. Might sound like a lot, but they hold so little oil it's cheap insurance. It's not that expensive and it made me feel better about it.

Definitely drain the gas from the carb. Some people say it's better to drain the gas from the tank, some say it's better to keep the tank full but rotate the gas out of it. Most agree non ethanol with stabilizers. I side step all of that and only run propane in both dual fuel generators, one 2000W inverter and one 9375W.

And now I realize that was probably way more than you wanted to hear, sorry. But the wife wondered if they really needed to be run that often also. Then we went through hurricane Ian last year. My two gens never missed a beat while a few neighbors who pushed theirs into a corner of the garage after the last time they used them had quite a few problems getting them to run or stay running anywhere near decently.

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Arizona Tom

· #6 · 15 d ago

I run my generator 2x a year, I change the oil every other year and I use ethanol gas, I don't drain the tank but I do run the carb dry.

I have a feeling that if you add oil and pull the cord a few times it will be good indefinitely and it'll be fine when you need it but you don't know till you fire it up.

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KoolAde2

· #7 · 15 d ago

I had bought a Generator before Katrina and my wife use it while we had no electric. I was out of town and couldn't get back for a couple days with the flights into NYC area.
When we got electric back I ran it dry and put it in storage didn't think about it until a few months ago I wanted to get a couple of inverter Gens.
I had hired a couple guys to clean up some old logs stacked against the back fence. So I told one of them they could have it get rid of it. We drug it out storage and put some gas in it and second pull started and ran without a hiccup. I have often wonder why people say to run it a couple times a year. I guess to make sure in their mind it would still run before the emergency happened and they needed it. I can tell you the young man was besides himselves. They ended up doing a great job.
That was a Harbor Freight and it had run my 220v Well without a problem.

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McMacy

· #8 · 15 d ago

We have two 4000ish watt generators, I run each every other month under load for about 45 mins. I change oil on July 4 weekend. Our gasoline is treated with Stabil & carb cleaner. I enjoy the process. We rotate 10-15 gals of year-old gas each month, too.

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cowboy1964

· #9 · 15 d ago

Yes it's good to run anything with an engine periodically. Seals dry up, etc, etc, etc. Obviously letting gas sit for too long (especially ethanol gas) is the biggest problem.

If it can run off propane, use that for the regular maintenance runs instead of gasoline. Gasoline can't gum things up if there is no gasoline.

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Sneeky

· #10 · 15 d ago

People saying they run after years in storage….yea, but do they produce electricity?

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Armtx77

· #11 · 15 d ago

KoolAde2 said:
I had bought a Generator before Katrina and my wife use it while we had no electric. I was out of town and couldn't get back for a couple days with the flights into NYC area.
When we got electric back I ran it dry and put it in storage didn't think about it until a few months ago I wanted to get a couple of inverter Gens.
I had hired a couple guys to clean up some old logs stacked against the back fence. So I told one of them they could have it get rid of it. We drug it out storage and put some gas in it and second pull started and ran without a hiccup. I have often wonder why people say to run it a couple times a year. I guess to make sure in their mind it would still run before the emergency happened and they needed it. I can tell you the young man was besides himselves. They ended up doing a great job.
That was a Harbor Freight and it had run my 220v Well without a problem.

Keeps the bearings from brineling from sitting in the same spot.

Reactions: 3

thess02

· #12 · 15 d ago

Arizona Tom said:
I run my generator 2x a year, I change the oil every other year and I use ethanol gas, I don't drain the tank but I do run the carb dry.

I have a feeling that if you add oil and pull the cord a few times it will be good indefinitely and it'll be fine when you need it but you don't know till you fire it up.

No machine lasts indefinitely. Good to hear your luck with ethanol fuel. I never trust a generator will work if it's sat unused for a long period of time. I've dealt with too many generators to trust in luck. And I never use ethanol fuel. I've seen too many issues with it.

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fordtrucksforever

· #13 · 15 d ago

Sorry, I say leave the generator new in box and dont touch it. Fuel is what kills gens from lack of use. The rubber components dont like modern gas. This same rubber can last longer without repeated saturation with gasoline.

There is also no danger of having a dry engine from sitting without oil circulating. Just flip the generator on its side and you are ready to fill with gas and start up.

I have older generators dating back over 60 years. Some have been drained then flushed of fuel and stored in not the best conditions. Even older points ignitions just need cleaned and checked for proper gap and so far they all fire right up.

It takes very little fuel residue to dry a few times and then the jetting is off on modern generators. Dried fuel leaves a film that wont wash clean without something stronger like acetone or lacquer thinner.

Every time you run the generator for its annual test flight, then run dry, there is some fuel left in bowl. It dries out and that is where the problem starts. Hondas and clones usually have a drain screw on the carburetor bowl. But over time the slight residue that still remains is detrimental to the rubber parts.

Just my 2 bucks worth(inflation you know). Your mileage may vary. Not applicable is all states or countries. Void where prohibited. No animals were harmed in posting this information. May cause cancer in California. Any similarities to real persons, living or dead is completely coincidental.

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cook

· #14 · 15 d ago

Just my opinon,doesn't mean its wrong or right.
I would start it now,just to make sure its works out of the box.Once you have done that,might as well run it evry 4 months with a load,just for peace of mind.I spent many hours in the sun replacing a starter on my car,then another day trying to figure out why it wouldn't start.
Turned out the starter I bought was "bad" from the factory.
Rare,but it happens.

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Arizona Tom

· #15 · 14 d ago

thess02 said:
No machine lasts indefinitely. Good to hear your luck with ethanol fuel. I never trust a generator will work if it's sat unused for a long period of time. I've dealt with too many generators to trust in luck. And I never use ethanol fuel. I've seen too many issues with it.

You may be right I may be lucky and I may have been lucky with this generator for the last 8 years, I "hope" my luck continues.

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MyPrepperLife

· #16 · 14 d ago

As a prepper, one of the most important lessons I've learned is that life with small engines is a lot easier if you use ethanol-free gas. I use it exclusively in my generators, my ATVs, my lawn tractor, and my tiller.

I store the ethanol-free gas in 5-gallon cans. I put fuel stabilizer in it when I buy it. I've used several different kinds of fuel stabilizer; currently I'm using PRI-G.

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Aceoky

· #17 · 14 d ago

MyPrepperLife said:
As a prepper, one of the most important lessons I've learned is that life with small engines is a lot easier if you use ethanol-free gas. I use it exclusively in my generators, my ATVs, my lawn tractor, and my tiller.

I store the ethanol-free gas in 5-gallon cans. I put fuel stabilizer in it when I buy it. I've used several different kinds of fuel stabilizer; currently I'm using PRI-G.

Same here .

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Bluwolf

· #18 · 14 d ago

I've used Stabil because it's available locally. But I've heard nothing but good things about PRI-G.

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thess02

· #19 · 14 d ago

Bluwolf said:
I've used Stabil because it's available locally. But I've heard nothing but good things about PRI-G.

I've tried Pri-G without any benefit over Stabil. Pri-G needs to be ordered, Stabil as you stated is available locally. I think it works better too. And I use ethanol-free 87 octane gasoline for all my equipment except of course my diesel generator. I feed it off-road diesel...$3.00 per gallon here.

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irv818

· #20 · 14 d ago (Edited)

Sneeky said:
People saying they run after years in storage….yea, but do they produce electricity?

And there is the real question.
Even the generator manufacturers say that the generator can lose magnetism if it isn't used for a period of time. In which case the engine can run but no electricity comes out.
No one wants to say exactly how long that "period of time" is.
There are hundreds of websites with info on how to restore the residual magnetism - but it's better not to have to mess with that.

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