Extended gasoline fuel tank for generator?

[Farmer17]

We just built a new house and I had the electrician install an outlet outside and a back-feed cut off switch on the panel so we can plug in a generator if power is out. There's only been one time I've lost power for a significant amount of time in the last 40 years in Oklahoma and that was about 6 years ago when a terrible ice storm knocked it out for about 4 days. We have a small Power Horse generator that will take care of the main things to get us by but I was wondering about attaching an external fuel tank so I don't have worry about refilling it all the time. Anyone have any experience with these?

 

[IAM Rand]

I have a Westinghouse generator. We just plug and play. Cut the outside power and go go go. It is a duel fuel, propane and gas. We got several larger tanks for extended use but the gas does much better. We had a neighbor's tree drop a branch on our newly installed outside power box. Had to use it for about a week. No problems at all. Ran all appliances that we would normally have done. Turned it off at night as we have neighbors that we didn't want to upset with the noise. Next step is to have some box or shelter to minimize the noise.

 

[Jon651]

While you certainly can easily add additional fuel capacity to a portable generator with a simple T (and maybe a quick-connect) added to the fuel line, you have to be careful to keep both tanks at the same height in order to prevent fuel from siphoning from one tank to the other if they are on different levels.

If you want to prevent siphoning, you can use a 3-way valve that lets you select which tank is feeding the gen with a simple rotation of the lever. Anything is possible. Smaller gens are usually gravity-fed and use 1/4" fuel lines and fittings, which are cheap and easy to find.

I'm not fond of the idea, however, if only because I want to keep a closer eye on my 5.5kw gen as it's running and I get around 6+ hours per tank. That gives me an opportunity to shut off the gen and let it cool a bit for refueling and an oil check before I crank it back up. I won't ever fill it when it's running. I also don't really run it continuously - usually on a 4-on/8-off schedule if it's cool out after a storm or 4-on/4-off if we need fans and a window AC unit if it's too hot (think hurricanes, not ice storms here...). Either schedule gives us plenty of time for the fridge and freezer to run plus our well pump while conserving fuel, which might be difficult to replace! This is how I ran it right after H. Milton.

Good luck!

 

[LVSteve]

In multiple threads I've seen comments about generators and checking the oil all the time. Are they really such oil guzzlers?

 

[Tom S.]

In multiple threads I've seen comments about generators and checking the oil all the time. Are they really such oil guzzlers?

It isn't that they are guzzlers, it's that their oil capacity is quite small, so any loss is magnified. IIRC, a 24k whole house Generac holds about a quart and a half.

 

[SSGRock]

We just built a new house and I had the electrician install an outlet outside and a back-feed cut off switch on the panel so we can plug in a generator if power is out. There's only been one time I've lost power for a significant amount of time in the last 40 years in Oklahoma and that was about 6 years ago when a terrible ice storm knocked it out for about 4 days. We have a small Power Horse generator that will take care of the main things to get us by but I was wondering about attaching an external fuel tank so I don't have worry about refilling it all the time. Anyone have any experience with these?

Very important! You still have to periodically cut if off and check engine oil.

 

[IAM Rand]

In multiple threads I've seen comments about generators and checking the oil all the time. Are they really such oil guzzlers?

You also have to worry about the oil breaking down if water gets into it. Better safe than sorry.

 

[GypsmJim]

I had the tin foil hat on and broke down and bought a generator for Y2K. Didn't need it for 10 years. I wired the house myself with second dedicated lines going to the sump pump, furnace, fridges and freezers.

Then, we had a massive power outage and it came in handy. Well, sort of.

My tank was always kept full, but it ran out after 8 hours. No problem, right....wrong. My lawn mower tanks were a backup, but eventually I had to go to a gas station to fillerup. They also had no power so no gas to pump. I ended up siphoning both cars in the garage.

My solution was a whole house NG generator a year later. Only needed it once in the last 15 years, but the ability to keep the food cold and the sump pumped when we are on vacation was worth it.

 

[SMSgt]

In multiple threads I've seen comments about generators and checking the oil all the time. Are they really such oil guzzlers?

Mine is not. I've never had to top off the oil on the rare occasions I've used it, the longest being about three days. My concern about storing a large amount of gas for the just-in-case scenario is the gas degrades rather quickly. I can store about 30 gallons of non-ethanol gas for hurricane prep, add a little Stabil to it, and it's fine for the six months of hurricane season. Then it gets dumped into the vehicles.

 

[NYlakesider]

You also have to worry about the oil breaking down if water gets into it. Better safe than sorry.

I use Mobil 1 in just about any thing that concerns oil!

 

[ggibson511960]

Generac Oil Capacity

It isn't that they are guzzlers, it's that their oil capacity is quite small, so any loss is magnified. IIRC, a 24k whole house Generac holds about a quart and a half.

All the Generac Guardian series units, 20-24 kW, use the same 900 cc air cooled V-twin engine with a 2 quart wet sump oil system. If run under significant load they burn oil, as does any loose tolerance air cooled engine. My 22 kW burns about 1/2 quart a day if holding up the house of A/C load. IMHO the tiny oil capacity is a major weakness. The low oil pressure switch will shut down the engine, if it works. I saw one Generac machine that failed on the second day of Houston’s hurricane Beryl outage. Threw a rod and split the crankcase. Ugly. Thy have another ugly little secret. The valve pushrods are not guided and captured well enough to ride out excessive valve lash. Pushrods and tappet followers can come adrift in the crankcase. They are cheap engines built to a price point. A telltale sign is the dirt dump simple magneto spark system without a distributor running on a 1/2 speed camshaft. Built just like a Briggs & Stratton law mower engine,

 

[BoydS]

Having lived near the Texas coast for over 50 years, we've experienced a few hurricanes over that time. After that 1st hurricane, it didn't take long to buy a generator. Over the years I've owned several and still own 3 today; 3kw Honda inverter, 5.5 kw B&S Craftsman (an antique) and a 13kw Duromax.

I never did hook up an auxiliary fuel tank, I guess because I never thought of it. To me it's not an issue to refuel, which at that time the oil is checked. I don't know how long you can run one without shutting it down for some maintenance, but I have run my larger unit (propane fuel) for a little over 45 hours continuously without issue.

I installed a 250-gallon propane tank last year that is dedicated to running my larger generator. This generator runs the whole house. I did install a soft start kit for the A/C unit as it pulls several amps during start up. The soft start limits those start up amps to about 14A.

I do keep about 15 gallons on hand. Mostly for my mowers and UTV. Keeping a gas stabilizer, as mentioned, is a good idea.