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No need to worry about old gas.
Check it out. This guy converted from gasoline to propane on his 8HP 27" Poulan snowblower.
Pretty ingenious...

 

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Roughly 20% power loss using propane on a low compression gas engine, but definitely no stale fuel problems.

It’s neat. I converted my generator to run on my houses propane. It’s great never having to worry about old gas.
 

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Roughly 20% power loss using propane on a low compression gas engine, but definitely no stale fuel problems.

It’s neat. I converted my generator to run on my houses propane. It’s great never having to worry about old gas.
Many generator companies are selling dual fuel generators out of the box. Gas/Propane. Pretty cool. One thing I learned from Sandy. When the power is out everywhere, gas pumps don't pump, but you can still get propane. I had to drive 30 miles to get gas.
 

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20% power loss converts that 8HP into a ~ 5.5 HP. This idea would work better on a 10HP or higher to compensate for power loss.
 

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20% power loss converts that 8HP into a ~ 5.5 HP. This idea would work better on a 10HP or higher to compensate for power loss.
Only depends on how it's injected.
So what they do to compensate is put in a second injector.

A typically car injector for say a 350-400 HP engine is 30lbs/hr or so. A propane injector is 160- 200 lbs/hour in gasoline terms. So with much bigger injectors, there's compensation for that.
 

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This is an interesting solution, I applaud people's creativity. It's not something I'd be looking to do, but I'm glad it works for him! Might need to add some weight on the bucket for balance (I didn't get to watch the video, maybe that's addressed), but it's at least some extra ballast for traction.

Many generator companies are selling dual fuel generators out of the box. Gas/Propane. Pretty cool. One thing I learned from Sandy. When the power is out everywhere, gas pumps don't pump, but you can still get propane. I had to drive 30 miles to get gas.
I guess if you have multiple 20lb propane tanks, that would help. Or a big propane tank for heat, which you could pull from.

The local hardware store doesn't need electricity to fill my tank, from what I recall of the filling process. Though if they're closed, I'm somewhat stuck, as there are a lot more gas stations around, than propane filling stations.

I have several gas cans, and I might be able to get some out of the car tanks, if needed. My gas cans have stabilizer, of course.

My current solution to the generator fuel dilemma is efficiency, my little 2000W inverter generator can run 1-3 days straight on my 7-gallon-total external tank setup, depending on the load. I haven't needed to drive 30 miles, fortunately, but I've waited ~45 minutes in line at the nearest gas station to fill up during an outage. Which was a good reminder that I want to be able to minimize my consumption, and maximize my fuel amount during a fillup run.
 

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This is an interesting solution, I applaud people's creativity. It's not something I'd be looking to do, but I'm glad it works for him! Might need to add some weight on the bucket for balance (I didn't get to watch the video, maybe that's addressed), but it's at least some extra ballast for traction.



I guess if you have multiple 20lb propane tanks, that would help. Or a big propane tank for heat, which you could pull from.

The local hardware store doesn't need electricity to fill my tank, from what I recall of the filling process. Though if they're closed, I'm somewhat stuck, as there are a lot more gas stations around, than propane filling stations.

I have several gas cans, and I might be able to get some out of the car tanks, if needed. My gas cans have stabilizer, of course.

My current solution to the generator fuel dilemma is efficiency, my little 2000W inverter generator can run 1-3 days straight on my 7-gallon-total external tank setup, depending on the load. I haven't needed to drive 30 miles, fortunately, but I've waited ~45 minutes in line at the nearest gas station to fill up during an outage. Which was a good reminder that I want to be able to minimize my consumption, and maximize my fuel amount during a fillup run.
I have a 5500 watt that runs overnight with a light load. I'm looking at these new ones with dual fuel so I have options. Can always go steal propane from the neighbor's grill in an emergency. (I use steal figuratively, not literally. Steal with permission)

Many stores have the pre filled 20LB propane tanks on the shelf.
 

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Only depends on how it's injected.
So what they do to compensate is put in a second injector.

A typically car injector for say a 350-400 HP engine is 30lbs/hr or so. A propane injector is 160- 200 lbs/hour in gasoline terms. So with much bigger injectors, there's compensation for that.
Well the thing with propane is that it has a lower BTU per gallon then gasoline. And adding more fuel doesn’t make up for the inefficiency on low compression gasoline engines.

The biggest benefits of propane are on engines with a compression ratio of 11:1 or greater. Propane has An octane rating as high as 112, plus the ideal a/f ratio is leaner then gasoline. 15.6 vs gasoline 14.7.

A proper build propane engine can match a gasoline engine, but there is loss putting propane on a gas engine. For a generator it’s a no brainer. The reason I bought a 7000 watt generator was because I was planning on converting to propane and was happy with it being able to sustain a clean 5000 Watt load without worry.

I think I overstated the power loss, it’s probably closer to 15%
 

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Well the thing with propane is that it has a lower BTU per gallon then gasoline. And adding more fuel doesn’t make up for the inefficiency on low compression gasoline engines.

The biggest benefits of propane are on engines with a compression ratio of 11:1 or greater. Propane has An octane rating as high as 112, plus the ideal a/f ratio is leaner then gasoline. 15.6 vs gasoline 14.7.

A proper build propane engine can match a gasoline engine, but there is loss putting propane on a gas engine. For a generator it’s a no brainer. The reason I bought a 7000 watt generator was because I was planning on converting to propane and was happy with it being able to sustain a clean 5000 Watt load without worry.

I think I overstated the power loss, it’s probably closer to 15%
Ya ,now, I haven't spent much time, if any, with engines with low compression like these. I'm basing my comments on my bias of higher compression, coming from a different perspective where it was assumed the compression was AT LEAST 11:1, or there about. So my ignorance probably bit me in the but.:plain:

What is the static compression of these engines? Somewhere I heard something about 8:1, is that right?

Exactly right on the AF ratio. It is much leaner. Which means cleaner.
 

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The issue is mainly due to cylinder volume and air/fuel ratio. If gasoline, at it's optimal af ratio delivers a lot more energy per unit volume than propane, then short of turbocharging the small engine to force more charge it, you are at a power loss, period! Increasing the af ratio of the propane will simply result in an overly rich mixture, and unburned fuel being blown out the exhaust . . . Without some form of boost, for a given max speed, the volume the engine can intake is fixed, and no amount of additional injectors will change that . . .
 

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Of greater importance than the energy density and power ratios is how long are you going to be able to run before that propane cylinder gets cold enough that it stops delivering fuel?
 

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Properly implemented, I think waste engine heat could be used to keep the bottle warm. I'm just not sure I'm ready to lug a 20lb gas cylinder around the driveway . . .
 

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Maybe the next progression after EFI from the manufacturers will be EFI with propane using smaller propane tanks. Or two tanks with a switch to switch over from the depleted tank to the full tank. There are kits for the homeowner to refill smaller camping cylinders from a larger tank.
 

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Ya ,now, I haven't spent much time, if any, with engines with low compression like these. I'm basing my comments on my bias of higher compression, coming from a different perspective where it was assumed the compression was AT LEAST 11:1, or there about. So my ignorance probably bit me in the but.:plain:

What is the static compression of these engines? Somewhere I heard something about 8:1, is that right?

Exactly right on the AF ratio. It is much leaner. Which means cleaner.

Using Honda as an example, gx390 8.2:1, gx270 8.5:1, gx200 8.5:1.

I have no idea what the old tecumseh flat head engines spec at, but I would assume something in the neighborhood of 7-8:1.
 

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Maybe the next progression after EFI from the manufacturers will be EFI with propane using smaller propane tanks. Or two tanks with a switch to switch over from the depleted tank to the full tank. There are kits for the homeowner to refill smaller camping cylinders from a larger tank.
Now there's a way to target a small segment of the market! ;)

"Who wants EFI?"
"Ok, and who also wants to run on propane?"
"Great, you three guys, have I got the machine for you!"

I mean no offense. I'm just not sure this is something that would have broad appeal.

EFI seems to have some barriers to entry as it is. And one thing that's been mentioned as an EFI benefit is possibly being more tolerant of gas going bad. But that EFI aspect wouldn't even apply with propane.
 

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I agree, limited market, very! Lol. However, I'm really looking for a private bridge for sale, charging to cross, and operating it in my retirement.

Now there's a way to target a small segment of the market! ;)

"Who wants EFI?"
"Ok, and who also wants to run on propane?"
"Great, you three guys, have I got the machine for you!"

I mean no offense. I'm just not sure this is something that would have broad appeal.

EFI seems to have some barriers to entry as it is. And one thing that's been mentioned as an EFI benefit is possibly being more tolerant of gas going bad. But that EFI aspect wouldn't even apply with propane.
 

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i am pretty sure there is a good reason they don't run propane on snowblowers. i am pretty sure it is the exact same reason it is not as commonly found on cars or at least around here. propane and the cold just don't get along so good. if you have a garage that you can keep the snowblower in that keeps it out of the extreme colds than ya it might not do too bad but i don't know how well i would trust it without. i believe even most of the setups used on cars have heaters built into them that tie into the vehicles cooling system to keep them warm and from freezing up.

has anyone considered considered using hydrogen on a snowblower? i know engines can run on it and you can get it in a tank like propane but not sure if it is cost effective or if there is an efficient way to run it other than injecting it into the air intake like most people seem to do. i also don't know how it would do in the cold
 
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