Generator - Gas or Diesel

[FMC1959]

Sorry in advance - long Questions

I currently have a 5.6Kw Wacker gen with a Honda engine but is too small for my needs at my new place I just moved to, and it is rural with more power outages & longer lasting than where I was previously.

I would love to get bigger but right now my budget is for something that is 10Kw continuous wattage. There is no Nat Gas in the area, and I do not want LP because the delivered price is very expensive. So I am looking at gas or diesel (not interested in solar or other non-typical systems)

First off, I assume that any diesel unit will run on home heating fuel? My understanding is that they are the same except car/truck diesel aside from some extra additives, which I could add?

I am looking at 3 units:

1) A New Yamaha EF12000DEX, 12Kw peak, 9.5 continuous, 22 HP V-Twin Yamaha gas engine, air cooled - for about about $4250 USD-tax in. (no room for negotiation)

2) A Used, less than 500 hour Honda EX12D 12Kw peak, 10Kw continuous, liquid cooled diesel, about $5200 USD, no tax, might be room for a little negotiation.

3)A New Yamaha EDL11000SDE, similar to the Honda, 12Kw peak, 10Kw continuous, liquid cooled diesel - about $7200 USD tax in (no room for negotiation)

There is also a Model:GL11000 Kubota Low Boy II which I like very much but very hard to find in Canada, new or used, and getting one in the US is tough with the borders closed because of COVID.

I have a vibrating plate and my Wacker generator with Honda engines, and like most people say, you can't go wrong with a Honda, excellent engines. However, in the small engine market Honda has a great reputation with their gas engines, are their diesel as good? I am looking for something that can handle an outage of a couple of days or more than a week if necessary.

Anyone know what the difference between the EX12D and the EB12D are?

Then the 2 Yamaha gens, they also have great engine reputation but my feeling is that an air cooled gas engine can be great but a liquid cooled diesel should be tougher and can last forever. And Yamaha also, their great reputation is for small gas engines, how are their diesels?

If I could find the Kubota at all, and a decent price, I have no qualms with their engines; I have a Kubota tractor for 13 years and it is bulletproof.

Not interested in Generac Kohler, or Honeywell home standby units.

Anyone know much about the Westinghouse gens that have been popping up everywhere, with Westinghouse motors???

The Yamaha gas with the 22HP V-Twin engine is very appealing at a good price, but do not want to make a mistake by not getting a diesel.

Any thoughts between the Honda and 2 Yamaha gens?

 

[p_mori7]

Get a 3-point PTO driven unit and power it with your tractor.

 

[FMC1959]

Get a 3-point PTO driven unit and power it with your tractor.

I had thought of that but I do not want my tractor to be out of use because it is running the gen

 

[AmericanMechanic]

If you plan to store fuel, diesel probably requires less-frequent rotation?

 

[FMC1959]

If you plan to store fuel, diesel probably requires less-frequent rotation?

Maybe, but I have about 10 x 55 gallon drums with vent caps to store either gas or diesel, currently 2 with gas and 2 with heating oil, I add stabilizer to both so it shouldn't a big issue.

 

[Firebrick43]

The core engine of most diesels will last longer especially long full load hours. However the fuel pumps and now particulate and catalytic converters will require maintenance at least once in a diesels life it will never payback especially if using for standby. There is a reason Caterpillar now sells more Natural gas generators than diesel.

Surprised LP is so expensive there? It by far the cheapest option here and the best solution for storage considering the nightmares of long term gas and diesel storage have.

 

[Firebrick43]

If you plan to store fuel, diesel probably requires less-frequent rotation?

If algae gets in a diesel tank it can cause more issues than gas going bad.

 

[FMC1959]

The core engine of most diesels will last longer especially long full load hours. However the fuel pumps and now particulate and catalytic converters will require maintenance at least once in a diesels life it will never payback especially if using for standby. There is a reason Caterpillar now sells more Natural gas generators than diesel.

Surprised LP is so expensive there? It by far the cheapest option here and the best solution for storage considering the nightmares of long term gas and diesel storage have.

For LP the key is delivered. I can fill up my 20 lb tank at Costco for around $10, but delivered here it is about 2.5 times that price when you include the tank rental and delivery fees they tack on.

 

[Firebrick43]

For LP the key is delivered. I can fill up my 20 lb tank at Costco for around $10, but delivered here it is about 2.5 times that price when you include the tank rental and delivery fees they tack on.

What if you own your own tank?

 

[FMC1959]

If algae gets in a diesel tank it can cause more issues than gas going bad.

Sounds like you are a bigger proponent of gas. I like the Yamaha 22HP V-Twin engine and I can get a Champion 11Kw - 9.2Kw continuous for about a $1000USD or Westinghouse and other brands for about 1/3 or 1/4 the price of the Yamaha but I want to make sure I get something I can count on long term

 

[FMC1959]

What if you own your own tank?

I don't know of anyone that owns their own tank; there might be many that do, but I do not know of any. My impression is that the initial cost is very expensive, then every 8-10 years it needs to be tested, also not cheap. Then at some point it probably gets old and by law needs to be replaced.

How much all this is versus renting, not sure, I would have to look into it.

 

[AmericanMechanic]

I don't know of anyone that owns their own tank; there might be many that do, but I do not know of any. My impression is that the initial cost is very expensive, then every 8-10 years it needs to be tested, also not cheap. Then at some point it probably gets old and by law needs to be replaced.

How much all this is versus renting, not sure, I would have to look into it.

How much would you like to store? You mentioned 55 gallon fuel tanks. What about the equivalent in 120 gallon (or smaller) LP tanks? Would you be able to haul these somewhere on a trailer to be filled? Use the tractor and pallets to move them?

 

[WittHay]

I am wondering how the little diesels start in cold weather. We have a mild climate but even a Honda gas motor is harder starting when the temperature is around freezing. When I think of power outages back east, ice storms and minus whatever temperatures comes to mind.

Agreed with propane, cheap when you pick it up in small tanks but expensive and a hassle when you have it delivered

 

[Bigblue&Goldie]

LP means no carbs to gum up or fuel to go bad.

 

[dubdoc]

I have a diesel 7500 watt and a gasoline 6800 watt. Go diesel or propane. Diesel is much easier on fuel, and propane won't go bad in storage.

 

[FMC1959]

How much would you like to store? You mentioned 55 gallon fuel tanks. What about the equivalent in 120 gallon (or smaller) LP tanks? Would you be able to haul these somewhere on a trailer to be filled? Use the tractor and pallets to move them?

Well, first thing is hauling propane tanks around is a bit of a hassle. They are heavy empty and very heavy once filled.

Most importantly, propane specialty stores have always stated that they must be transported standing up. Otherwise there is the risk that the pressure build up can blow the top of the tank off if you were to lay the tanks on their side. This alone means for 100 lb tanks I would need a pickup, which I do not have. So limited to 40 or 30 lb tanks, I don't think that would be very practical.

 

[AmericanMechanic]

Well, first thing is hauling propane tanks around is a bit of a hassle. They are heavy empty and very heavy once filled.

Most importantly, propane specialty stores have always stated that they must be transported standing up. Otherwise there is the risk that the pressure build up can blow the top of the tank off if you were to lay the tanks on their side. This alone means for 100 lb tanks I would need a pickup, which I do not have. So limited to 40 or 30 lb tanks, I don't think that would be very practical.

Makes sense. You mentioned a tractor. I thought maybe use a trailer. Bolt or strap 420 lb tanks (or other sizes) to pallets and move them with the tractor.

A 55 gallon drum of fuel is going to be similar in weight.

 

[FMC1959]

I am wondering how the little diesels start in cold weather. We have a mild climate but even a Honda gas motor is harder starting when the temperature is around freezing. When I think of power outages back east, ice storms and minus whatever temperatures comes to mind.

Agreed with propane, cheap when you pick it up in small tanks but expensive and a hassle when you have it delivered

My tractor has glow plugs and has always started except one instance where it was super cold. But it has a block heater, so I plugged it in and a couple of hours later it started.

The Yamaha and Honda diesel, I am no expert and actually looking for all info possible, but I assume they do not have glow plugs, so not sure how easily they would start in the cold.

Anyone with experience with these type of engines, please chime in

 

[FMC1959]

Makes sense. You mentioned a tractor. I thought maybe use a trailer. Bolt or strap 420 lb tanks (or other sizes) to pallets and move them with the tractor.

A 55 gallon drum of fuel is going to be similar in weight.

I am in a small village, there is nothing close by that I could use my tractor to haul the LP tanks to.

The 55 gallon drums fit easily in my cargo van. I can pump fuel into them without removing them from my van. Once home I use my tractor to remove them and place them where I need.

 

[FMC1959]

LP means no carbs to gum up or fuel to go bad.

This is true but as previously mentioned, there are more cons than pros with LP, for my personal needs.

My experience with diesel is limited to my tractor, small BX Kubota always runs. Aside from oil changes and 1 new battery, never done anything to it and it runs fantastic.

 

[FMC1959]

We use a 70 kw with j.d. diesel power. It has a coolant heater so it starts quickly.

I saw an ad for a used 50Kw gen that had a John Deere 4 cyl turbo diesel (pe4024hf285), 50 Kw would be awesome, could easily power the whole house. But the were asking $7500USD, a bit more than I can spend right now. It also had over 20,000 hours, maybe ok for a diesel but I tried doing some research on JD turbo diesels, couldn't find much. Plus it was 3 phase 500 volt.

Between the price, the hours and figuring the turbo might need maintenance/replacing, 3 phase, 500 volt....this would have been nice but would need a lot of work & money to fit my needs.

 

[FMC1959]

I have a diesel 7500 watt and a gasoline 6800 watt. Go diesel or propane. Diesel is much easier on fuel, and propane won't go bad in storage.

Could you say what your diesel is and what, if any issues you encountered.

Then what is the gasoline unit and why you seem to not recommend gasoline?

If it is a $500 Homelite or Coleman, I can see why you would say this. I had a Homelite about 20 years ago, 5.5Kw. First time I used within a couple of hours there was engine oil in the airlifter, it was smoking and had a really bad cough!

Costco took it back and that is when I bought the Wacker/Honda.

 

[FMC1959]

I just wanted to add, I understand people responding with possible alternatives, much appreciated.

But LP is just not practical for me. I can't haul big LP tanks around, I do not have a pickup. They are also heavy; I am 61 and on disability pension having gone through chemotherapy in 2010, again in 2015, and currently going through a newer kind of chemotherapy replacement to manage my Leukemia.

So hauling around LP tanks, I can do it if necessary, but would rather not.

Having it delivered is very expensive in my area and also in the event of an outage that lasts more than a day, I am at the mercy of the propane company and when they can deliver, especially at a time they are probably very busy.

Gasoline or diesel (or home heating fuel), I can throw empty drums into my van, drive as far as I need to to find a fuel station that is operating, fill them up while they are in my van and remove them with my tractor once I get home.

So the latter is by far easier for me rather than what I consider a hassle with LP.

 

[Zebu Fellenz]

If you're looking at gas power you might also want to look at engine drive welder/generators. There are quite a few options in the $4-5k range for new machines, maybe just under $4k for a basic machine.

 

[Kevin54]

For a generator, I would go with diesel. Gas today, if you don't put in a bunch of additives, will turn to **** and gum stuff up. And generators might sit for a long while before you need to use it. I can leave my CUT sitting out in the winter for months and it always starts right up. My gas generator.....let it sit 2 months and it won't start.

 

[FMC1959]

If you're looking at gas power you might also want to look at engine drive welder/generators. There are quite a few options in the $4-5k range for new machines, maybe just under $4k for a basic machine.

Yes, I saw some. There was a decent Lincoln, used, 10Kw continuous use, with a diesel engine, but it sold. I don't recall the price but it was interesting. The one issue is where the gen would have to be situated outside my house is completely away from my workshop/garage, but still something I might consider if the price is hard to say no to.

 

[FMC1959]

For a generator, I would go with diesel. Gas today, if you don't put in a bunch of additives, will turn to **** and gum stuff up. And generators might sit for a long while before you need to use it. I can leave my CUT sitting out in the winter for months and it always starts right up. My gas generator.....let it sit 2 months and it won't start.

I agree, which is why I am leaning towards the diesel.

 

[FMC1959]

I am surprised no one has weighed in on the 2 Yamaha and 1 Honda gen. I know there are many that are fans of both brands. I am trying to see if anyone can attest to either brands reliability when it comes to diesels.

Then the other option being the 22HP Yamaha gas engine, I know that generally speaking, contractors and many others find equipment with Yamaha engines to be great. I am just trying to ask about this gas gen because generators have to work very hard for long periods of time compared to snow blowers, and various other construction equipment. A short 2-4 hour power failure a generator will be running hard for that long, never mind an outage of multiple days. A one week outage, a generator will put in more hard work hours than a snow blower, a concrete power trowel, a wood chipper, and various other pieces of construction equipment that get used intermittently, would over the life of the tool.

So as much as I think a Yamaha or Honda gas engine gen would be great, anyone have experience using these for long periods of time?

 

[bob15]

Maybe I missed it, but why the traveling to fill LP tanks. How hard is it to call a dealer and have them deliver/fill up a 500 or 1000 gallon LP tank? It will be cheaper than you filling up smaller tanks and it will last many more days than 55 gallon drums.

DF is fine if you treat it for allege and make sure you have an anti-gel conditioner. If you get any water, bacteria or fungus in your fuel, it can play havoc on your system. Also make sure your charging is up to snuff. Find fuel after a major storm is easier said than done. Roads can and will be tough to navigate and other people will also be on the road also looking for fuel, so it might be harder to find than you think. So make sure you have a big enough tank (something better than 55 gallon drums).

Gasoline ***** for a generator. Gas goes bad fast and storage of 100's of gallons is best served with something better than 55 gallon drums. Again, finding gasoline after a major storm isn't as easy as you think.

Sorry but LP is still the best option. As for finding fuel after a major storm, what I said is coming from experience of losing power for 11 days after an October snow storm shut down most of New England back in 2011. I was was filling my generator with 5-6 gallons of gasoline in the morning before work, another 7 after work and topping it off with another 2-3 before bed. I did this for 11 days due to needing electricity for a sump pump, well pump, fridge and freezer. It was not fun, nor easy to find gas.

Oh and if you do go out to get fuel, make sure you have cash on hand because stations weren't excepting cards and the atm's didn't work due to no electricity.

 

[bob15]

The core engine of most diesels will last longer especially long full load hours. However the fuel pumps and now particulate and catalytic converters will require maintenance at least once in a diesels life it will never payback especially if using for standby. There is a reason Caterpillar now sells more Natural gas generators than diesel.

That is also one of the reasons Cat got out of the OTR engines and just stuck with off-road.

 

[FMC1959]

Maybe I missed it, but why the traveling to fill LP tanks. How hard is it to call a dealer and have them deliver/fill up a 500 or 1000 gallon LP tank? It will be cheaper than you filling up smaller tanks and it will last many more days than 55 gallon drums.

DF is fine if you treat it for allege and make sure you have an anti-gel conditioner. If you get any water, bacteria or fungus in your fuel, it can play havoc on your system. Also make sure your charging is up to snuff. Find fuel after a major storm is easier said than done. Roads can and will be tough to navigate and other people will also be on the road also looking for fuel, so it might be harder to find than you think. So make sure you have a big enough tank (something better than 55 gallon drums).

Gasoline ***** for a generator. Gas goes bad fast and storage of 100's of gallons is best served with something better than 55 gallon drums. Again, finding gasoline after a major storm isn't as easy as you think.

Sorry but LP is still the best option. As for finding fuel after a major storm, what I said is coming from experience of losing power for 11 days after an October snow storm shut down most of New England back in 2011. I was was filling my generator with 5-6 gallons of gasoline in the morning before work, another 7 after work and topping it off with another 2-3 before bed. I did this for 11 days due to needing electricity for a sump pump, well pump, fridge and freezer. It was not fun, nor easy to find gas.

Oh and if you do go out to get fuel, make sure you have cash on hand because stations weren't excepting cards and the atm's didn't work due to no electricity.

The diesel fuel I have stored I use this https://www.amazon.com/gp/product/B001JT5MGI/?tag=atomicindus08-20
So far, I have not had any issues and it is supposed to keep it from gelling in the winter. The thing about algae, this and another previous post is the first I hear about it. How long can diesel be stored with zero additives before it can have issues?

I suspect the algae problem would be if water get in? I have 2 drums, about 100 gal currently in drums where one hole/spout has a sealed cap and the other is a vented cap like this
https://www.yankeecontainers.com/c/vent-plug-in-drum-plug/
then a tarp covers them and they are under an awning that is on the outside of my garage. I do not know how much water or formation of moisture would be required to create algae issues, but rain should not get into the drums.

For the propane, I need to inquire where I am now, about 45 minutes from where I was in the burbs. There, the tank rental was 140USD/year for a 250 lb tank. If you did not use x amount per year, they would tack on an extra $40USD. This 250 lb tank was about $300USD to fill when it was pretty empty (below 20 on the gauge... PSI?). Delivered propane is not cheap here. Furnace, stove, dryer or anything else, propane is easily the most expensive option, by close to double the next expensive.

I have a buddy in Nova Scotia who has 3 x 350 lb tanks, they charge him $75 USD, not for each, but all 3 tanks. I do not know what the fill price is though.

 

[bob15]

With the LP tanks, are you sure they are 250 & 350 lbs and not gallons? Most tanks are 120, 300, 500 & 1000 gallon. Largest in pounds is around 100 (RV tank).

DF can start forming allege in as little as 6 months. I spent 17+ years working for a DF pump, injector & filter manufacturer in R&D. I spent a couple years working on filters & fuel conditioners.

One issue I've seen with drums is condensation which will create enough water which will lead to issues such as allege. Full drums not as bad, but the potential is there. Also make sure there is any rust on the bottom of the drums that can cause leakage.....

If you're heart is set on a DF generator, make sure you rotate your fuel and treat it from a reputable company that has been around decades and not a "fly-by-night" outfit. Also keep a supply of fuel filters handy....just-in-case.

Can you buy a 500 gallon LP tank? I own mine, so I can deal with whomever I want and anything above 300 gallons delivered, there is a discount.

 

[Pontiac787]

If you go with diesel would it make more sense to buy a 175-200 gallon fuel oil tank and have an oil company fill it for you? My only concern would be the fuel gelling in the winter.

 

[danski0224]

I'd be looking at 1800 rpm units vs 3600 rpm units. I know this is available in diesel, not sure about gasoline.

I would probably start by looking at the load and fuel consumption specs. Then guesstimate your load, and how long you want to run it.

That will tell you how much fuel to have onhand.

If you do not own a diesel vehicle, it will be easier to rotate a stock of gasoline. Of course, diesel is "safer" to have in storage than gas. Either way, I would not want a homebrew fuel storage and transfer system. At the very least, if something happens, you will likely be SOL with insurance claims if there is a large quantity of fuel stored onsite.

I have not had any issues keeping gas for 2+ years with a fuel stabilizer. Had a Honda carb **** up, it is fine now with a new one (Honda, not a Chinese copy)... not complaining much because it is over 10 years old.

Diesel or gas, you will need to run it at least every couple of weeks until it gets to temperature and put it under load for maintenance.

I'm not so sure about buying a used commercial grade generator without a detailed maintenance history or even oil analysis.

"On road" and "off road" diesel are the same since at least 2007 with the exception of the red dye in "off road" (no road tax) diesel.

Not so sure about heating oil. The sulfur content may not be to the same standards as engine fuel. I'd certainly check into it, in detail.

 

[FMC1959]

With the LP tanks, are you sure they are 250 & 350 lbs and not gallons? Most tanks are 120, 300, 500 & 1000 gallon. Largest in pounds is around 100 (RV tank).

DF can start forming allege in as little as 6 months. I spent 17+ years working for a DF pump, injector & filter manufacturer in R&D. I spent a couple years working on filters & fuel conditioners.

One issue I've seen with drums is condensation which will create enough water which will lead to issues such as allege. Full drums not as bad, but the potential is there. Also make sure there is any rust on the bottom of the drums that can cause leakage.....

If you're heart is set on a DF generator, make sure you rotate your fuel and treat it from a reputable company that has been around decades and not a "fly-by-night" outfit. Also keep a supply of fuel filters handy....just-in-case.

Can you buy a 500 gallon LP tank? I own mine, so I can deal with whomever I want and anything above 300 gallons delivered, there is a discount.

I don't know why they refer to some in gallons and other by pounds. 4 pounds is a (US) gallon in LP.

https://www.google.ca/search?sxsrf=...gEEMS4yMZgBAKABAaoBB2d3cy13aXo&sclient=psy-ab

This is an RV type 100 lb (~25 gal) tank that I referred to in previous posts. Which are a PIA to haul around and need to be carried standing and strapped in a pickup.

https://www.costco.ca/pro-grade-45....-without-gauge-(empty).product.100339105.html

At my previous home I had a propane fireplace and added an outlet for my BBQ. I had a 250 lb (~60 gal). Here is a link of a company that rents and delivers. The 2 larger "sausage" tanks are in gallons, 500 & 1000. But the smaller one, that looks pretty similar to the one I had, and it is expressed in pounds - 420 lb.

My buddy is renting 3 of these (a bit less a 350 lbs each) for a total of $75 a year...I can't get that deal here. I am curious what size you have and how much it cost. I figure they are pricey to buy, and I don't know about where you are but here they are stamped with a date, usually 8-10 years down the road. Most 20 lb tanks are chucked in the garbage as they are worth the price to test and are usually all rusty.

But a big tank, I am sure to have it tested ain't cheap, and then at some point, after x number of tests/years, it will probably need to be replaced.

 

[FMC1959]

...DF can start forming allege in as little as 6 months. I spent 17+ years working for a DF pump, injector & filter manufacturer in R&D. I spent a couple years working on filters & fuel conditioners....

Would you know if most diesel engines do fine on home heating fuel or not?

Here diesel fuel at the pump has about 30-40% in "the government calls it road and save the environment tax" but really is "we need money" tax. So home heating fuel is vey cheap....even delivered compared to diesel at the pump. AGR diesel does not have the road taxes but I believe you need to have some kind of "I am a farmer" permit it to buy it.

 

[FMC1959]

One issue I've seen with drums is condensation which will create enough water which will lead to issues such as allege. Full drums not as bad, but the potential is there. Also make sure there is any rust on the bottom of the drums that can cause leakage.....

Forgot to mention, I have about a dozen drums, they are all some kind of poly/plastic, so no rusting

 

[FMC1959]

If you go with diesel would it make more sense to buy a 175-200 gallon fuel oil tank and have an oil company fill it for you? My only concern would be the fuel gelling in the winter.

If I didn't have all the drums (got them at an auction for $5 a piece), a large 200 gallon drum would definitely make sense. But I have these and they are just small enough that I can move them around and off my van with my tractor.

 

[Firebrick43]

That is also one of the reasons Cat got out of the OTR engines and just stuck with off-road.

No, not really, it’s more about class 8 manufactures deciding to only offer their own engines. And they are still sort of in the on road market, the bigger Navistar maxforce engines are cat Iron but navistar certifies them. By the time tier 4 was implemented the differences in emissions for an engine over 100hp are so close to the requirements of on road emissions.


I am not a proponent of gas, diesel, or propane engines. They all do things well in different areas. For small standby use I would never recommend a diesel. They are not loaded (50%+ on average) enough nor used enough hours to overcome higher ownership cost. If one was off grid and using for large loads and charging a large battery bank i would recommend diesel

For a small back up I would always chose an LP which is really the same engine as a gasoline except the carb and sometimes the valves. But lp is the cleanest and most stabile fuel.

If dead set against LP, I would find ethanol free gas, install water traps, and stabil the **** out of it before ever getting a diesel. You can replace a small gas engine a lot of the time, for not much more than the cost of a fuel pump on a diesel.

Some diesels cold start ok but a lot don’t and then you have to maintain glow plugs or intake heaters. Diesel require 3 to 4 times the oil during a change. Air leaks on a fuel system, algae in the fuel, or water can cause just as much trouble as gasoline that has gone bad but the gasser you flush and continue on.
Water to a diesel is death to injection pumps, and air leaks or running out of fuel can be hell to get going again depending on the engine. Then today’s low sulfur diesel is hard on injectors.

I am not dogging diesels as I have been using them my whole life on a farm, on the flight line, and for the last 15 years I have a 2 ton truck with one and worked for caterpillar. They just shine and make much more financial sense once you burden them over 50% of load on average. I don’t suffer from diesel fanaticism nor the the fantasy that less gph or better mpg translates into better cost per hour or cost per mile

 

[FMC1959]

I'd be looking at 1800 rpm units vs 3600 rpm units. I know this is available in diesel, not sure about gasoline.

I would probably start by looking at the load and fuel consumption specs. Then guesstimate your load, and how long you want to run it.

I have done my calculations and 10Kw continuous power is the bare minimum I need.

That will tell you how much fuel to have onhand.

If you do not own a diesel vehicle, it will be easier to rotate a stock of gasoline. Of course, diesel is "safer" to have in storage than gas. Either way, I would not want a homebrew fuel storage and transfer system. At the very least, if something happens, you will likely be SOL with insurance claims if there is a large quantity of fuel stored onsite.

I have tractor that runs on diesel. I keep the drums far from the house, if by some freak of nature they all blew up, a shed would be lost but the house would be in no danger

I have not had any issues keeping gas for 2+ years with a fuel stabilizer. Had a Honda carb **** up, it is fine now with a new one (Honda, not a Chinese copy)... not complaining much because it is over 10 years old.

Diesel or gas, you will need to run it at least every couple of weeks until it gets to temperature and put it under load for maintenance.

I'm not so sure about buying a used commercial grade generator without a detailed maintenance history or even oil analysis.

"On road" and "off road" diesel are the same since at least 2007 with the exception of the red dye in "off road" (no road tax) diesel.

Not so sure about heating oil. The sulfur content may not be to the same standards as engine fuel. I'd certainly check into it, in detail.

This is where I get mixed responses. Many tell me they run tractors and other equipment on home heating fuel. Less, but some others feel it is not a good idea.