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Propane and Natural Gas Fuel Delivery and Tuning Discussion about the care and feeding of Propane and Natural Gas Engines.

Propane and Natural Gas Fuel Delivery and Tuning

Natural Gas Engines in Cold Weather


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  #41  
Old 10-26-2018, 12:10:21 AM
dkamp dkamp is offline
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Default Re: natural gas engines in cold weather

Well, it depends on the circumstance. Initially (like, when you do the first startup of a new system with a really, really big engine and a long supply pipe), you'll probably need to uncap the drip leg and crack the fuel supply valve and let it flow a little gas through, then cap the drip leg, and push the 'prime' button on the demand regulator (if yours has one), then start it.

If your supply pipe is short, another easy way is to crank the engine, and feed it a shot of something flammable so it'll start, and keep it running that way 'till it draws fuel gas vapors on it's own. An inexpensive propane torch head threaded on a bottle... open the fuel valve just a little, and stuff the head (not lit... juts flowing) into the air inlet will frequently be enough to fire up an engine... just keep it there for a little while, and when the main fuel system finally flows clean fuel gas, the engine will start sounding different.

Which is something that should be noted- most engine guys will listen to a gasoline motor and know when it's sounding 'rich' or 'lean'.

When running a gaseous fuel engine, it acts just the opposite of a liquid fuel engine...
...so when you're 'priming' it with an auxiliary propane bottle, when the engine starts sounding 'lean', pull the propane bottle out. ;-)
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Old 10-26-2018, 07:44:27 AM
cjjmw cjjmw is offline
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Default Re: Natural Gas Engines in Cold Weather

Interesting.


All of the "conversion kits" I see online look like they're nothing more than the regulator and just a spacer with a tube in it to feed the fuel. The spacer gets mounted at the inlet of the carburetor. Some are even just a cheesy nozzle that aims down the throat of the carb.

Is there no metering device other than the regulator? They don't even look like a venturi, unless I missed something.

If that's the case, to convert the small 8HP Briggs I have, all I need to do is drill and tap the air filter elbow and connect it to a regulator and I'm done.

That seems way too easy though.
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  #43  
Old 10-26-2018, 09:11:34 AM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

There is a little more to it than that, but basically you are correct. The fuel inlet to the engine needs a vacuum signal, so either a venturi of its own, or the one on the liquid fuel carb.
The regulator meter fuel from the vacuum signal it gets from the carb.
There are things like fuel lock offs that should be installed as well. The regulator will stop the fuel flow when no vacuum is present, but for safetys sake you want another lock off so no gas can flow when the engine if not in use.
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  #44  
Old 10-26-2018, 09:26:14 AM
Odin Odin is offline
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Default Re: Natural Gas Engines in Cold Weather

The IMPCO system used for LPG forklifts has a demand regulator heated by the jacket water so it won't freeze, and then a venturi in the air pipe that makes the engine suck in the fuel so the demand regulator gets the vacuum signal it needs to operate properly. A simple needle valve is used to trim the mixture to make the engine happy, and can indeed be set by how the engine sounds and feels.

I would think a natural gas system could be implemented in similar fashion, but the jacket water loop enclosing the regulator would not be necessary since it wouldn't be vaporizing a liquid fuel.
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  #45  
Old 10-26-2018, 09:43:46 AM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

I did dual fuel conversions on manlifts, from little Subaru-Robins, to Ford 300's and they were all done like you say. Easy job.
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  #46  
Old 10-26-2018, 09:44:57 AM
cjjmw cjjmw is offline
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Default Re: Natural Gas Engines in Cold Weather

How critical is the design of the venturi?
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  #47  
Old 10-26-2018, 10:45:12 AM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

If there was no venturi at all, it may have trouble metering at low power/idle. but in general I'd say not very critical. You just need a vacuum signal to the regulator to "tell it" how much airflow is going thru the throttle plate.
Having said that, if this is going to be a dedicated NG engine, best results will be had with a vapor carb. Dual/triple fuel is always a compromise between being able to burn more than one fuel, and being optimized for any.
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  #48  
Old 10-26-2018, 10:53:37 AM
ronm ronm is offline
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Default Re: Natural Gas Engines in Cold Weather

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Originally Posted by Odin View Post
The IMPCO system used for LPG forklifts has a demand regulator heated by the jacket water so it won't freeze, and then a venturi in the air pipe that makes the engine suck in the fuel so the demand regulator gets the vacuum signal it needs to operate properly. A simple needle valve is used to trim the mixture to make the engine happy, and can indeed be set by how the engine sounds and feels.

I would think a natural gas system could be implemented in similar fashion, but the jacket water loop enclosing the regulator would not be necessary since it wouldn't be vaporizing a liquid fuel.
That is the same as the OEM systems that used to be on LP farm tractors. The converter was a demand regulator, didn't flow any gas until the engine started. The converter was fed liquid & circulated water to vaporize it. They had a liquid valve & a vapor valve on the tank. You had to start it on vapor & switch to liquid when the water got warm. The engine would not develop full power on vapor.
To somewhat relate to the original subject, imagine that, there was a fad here at one time to bring LP tractors in from Texas where they were common. Dairies & feedlots bought them to be easier starting than Diesels in cold weather...oops...found out that at -20, LP does not flow well at all. They all went back to Diesels after a couple years, at least they would start with a snort of ether if plugged in...
Apologize if this is redundant...I gave up on plowing through all the OT BS about A/C...
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  #49  
Old 10-26-2018, 11:06:18 AM
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Default Re: Natural Gas Engines in Cold Weather

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Originally Posted by cornbinder89 View Post
If there was no venturi at all, it may have trouble metering at low power/idle. but in general I'd say not very critical. You just need a vacuum signal to the regulator to "tell it" how much airflow is going thru the throttle plate.
Having said that, if this is going to be a dedicated NG engine, best results will be had with a vapor carb. Dual/triple fuel is always a compromise between being able to burn more than one fuel, and being optimized for any.
I've been on the fence about it being dual\tri fuel........
Part of me is tired of dealing with gasoline in something that is rarely used, and ethanol just makes it even more fun.

I was thinking two venturis (gasoline carb + the added one) didn't sound optimal.....

I'm guessing if I wanted to make it strictly LPG\NG all I'd need to do is drill out the main jet so a fairly large size and connect directly to that. I highly doubt anyone makes or made an actual vapor carb for a small 8HP B&S engine from 1992.

The two liquid cooled 4 cylinder Hesco units from the 1980s I'm doing for my boss very likely have such a thing, but finding them would be the challenge.
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  #50  
Old 10-26-2018, 11:11:11 AM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

I worked on M.A.N. powered city buses that were LP. They were a bear to get running in Chicago's winter. At -23 there just wasn't tank pressure to feed the big M.A.N even when they used multiple tanks. They only used liquid draw, with a pair of heated regulators and a single big mixer.

---------- Post added at 10:11:11 AM ---------- Previous post was at 10:07:51 AM ----------

It's been a while since I went searching for LP stuff, but there used to be a lot of carbs for different sized equipment.
I have a 525 CID Buda I hope someday to convert to LP. Right now it has a BIG 1bbl gas carb.
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  #51  
Old 10-26-2018, 11:13:33 AM
cjjmw cjjmw is offline
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Default Re: Natural Gas Engines in Cold Weather

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Originally Posted by cornbinder89 View Post
I worked on M.A.N. powered city buses that were LP. They were a bear to get running in Chicago's winter. At -23 there just wasn't tank pressure to feed the big M.A.N even when they used multiple tanks. They only used liquid draw, with a pair of heated regulators and a single big mixer.

---------- Post added at 10:11:11 AM ---------- Previous post was at 10:07:51 AM ----------

It's been a while since I went searching for LP stuff, but there used to be a lot of carbs for different sized equipment.
I have a 525 CID Buda I hope someday to convert to LP. Right now it has a BIG 1bbl gas carb.
525 cubic inch..............with a 1 barrel carb!?!?!
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  #52  
Old 10-26-2018, 12:12:51 PM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

Yep, BIG 1bbl, dual ign (coil and mag) and electric and HAND CRANK! I hand cranked it once to see if I could.
1800 rpm generator, 62.5 kva

---------- Post added at 11:12:51 AM ---------- Previous post was at 10:58:44 AM ----------

I suppose because it is a 1800 rpm generator engine, having a carb that meters over a broad range of speed wasn't a concern.
It just need to idle and then you pull the hand throttle wide open and the gov thottle takes over from there.
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  #53  
Old 10-26-2018, 12:27:55 PM
cjjmw cjjmw is offline
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Default Re: Natural Gas Engines in Cold Weather

All of the smaller engines I've been looking at that are available in gasoline, LPG or natural gas all drop in power when used with different fuels.

For example, gasoline seems to give the most power, 2nd is LPG and the lowest output is natural gas.

Is this because the fuel produces less power, or is it because the engines aren't actually designed for the specific fuel?

It seems like the higher octane of LPG should produce more power than gasoline of the engine is setup for it, no?
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  #54  
Old 10-26-2018, 12:28:57 PM
Odin Odin is offline
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Default Re: Natural Gas Engines in Cold Weather

I remember having the venturi out of one of the forklift engines, a Clark GPX20E. This forklift's Impco venturi actually was a variable venturi, connected to the throttle linkage.

Inside the tube was a ball on a stick with a couple holes in it, the throttle linkage changing the position of the ball relative to the venturi's flow restriction. The propane then entered on both sides just downstream of the venturi, positioned so that as the throttle ball moved it would restrict the airflow like normal and in doing so change the amount of vacuum felt by the regulator.

This arrangement made the engine's mixture a little bit more rich at idle so it would run smooth, but then lean out when revved up for fuel economy. Very clever arrangement, it would always fire up easily and run well. We sold this truck a few years ago to replace it with a newer forklift that had additional safety features and emissions controls for indoor operation, the new one is equipped with EFI.

That said, I never really let the forklift engines sit out in the cold. They always stayed in the welding shop at night, and when taken outside usually would not be turned off until they came in again.

I do still have a Clark C500 with a Continential F135 flathead in it that uses the Impco system. Maybe I should pull the intake hose off and have a look at how the venturi is actually situated to give you some ideas. Since a natural gas venturi would be similar to one used for propane, just a larger jet to handle the different mixing ratio.
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  #55  
Old 10-26-2018, 01:16:43 PM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

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Originally Posted by cjjmw View Post
All of the smaller engines I've been looking at that are available in gasoline, LPG or natural gas all drop in power when used with different fuels.

For example, gasoline seems to give the most power, 2nd is LPG and the lowest output is natural gas.

Is this because the fuel produces less power, or is it because the engines aren't actually designed for the specific fuel?

It seems like the higher octane of LPG should produce more power than gasoline of the engine is setup for it, no?
Well its really all of the above. Propane has less heat than gasoline and NG less yet.
Gasoline engine have lower than ideal compression ratio for the other fuels. The M.A.N's I worked on were converted diesels, not gasoline and were built like a diesel with the combustion chamber in the piston not the head.
IIRC the compression ratio was 12.7:1 so lower than diesel but higher than gasoline. They had an accessory drive fitted where the injection pump would go, and distributor and coil. On the intake side they had a big mixer and throttle plate.
The sparkplug was where the injector was fitted on the diesel version. The whole engine was tweaked for LP only operation.
Every other LP engine I've been around with the exception of some real big NG Cat's and Wauk's were converted gasoline blocks. Some mfg like GM and IHC offered higher compression pistons for LP versions of their engines, but they were never in the high 12's like the M.A.N's were. Also this was a time when gasoline engines topped out at the low 8's :1 and heavy duty gasoline were in the low 7's high 6's.
Also both dry fuels are slower burning when compared to gasoline, (higher "octane" so to speak) so more initial and dynamic advance could be used. So for ideal operation you would want a totally different distributor with different advance curve.

---------- Post added at 11:52:03 AM ---------- Previous post was at 11:48:38 AM ----------

"octane" is a flame speed/detonation rating not heat content so a fuel can have a high rating in one and low in the other.

---------- Post added at 12:09:25 PM ---------- Previous post was at 11:52:03 AM ----------

The Hyatt hotel in Rosemont,IL (Sheraton when I worked there) Generated all its own power, and was off grid. It had a powerhouse on the north east side of the property that housed 3 Cats and one Wauk along with a CAT turbo diesel for back up emg power.
A Satellite view of the property still shows the powerhouse so I assume it is still in operation. They didn't give tours when I was there but they might if you asked.

---------- Post added at 12:16:43 PM ---------- Previous post was at 12:09:25 PM ----------

Correction, when I zoom all the way in on Google maps, it shows the power house, but views zoomed further out show it to be a parking lot. I wonder what happened to everything in the powerhouse? Since the waste heat was used both for heating and cooling, it would have taken a big retro-fit to eliminate the powerhouse and tie to the grid.

https://www.hotels.com/search/search...m-0-children=0


See if that works
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  #56  
Old 10-28-2018, 07:41:47 PM
cjjmw cjjmw is offline
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Default Re: Natural Gas Engines in Cold Weather

Ok,

So the one LPG / NG Briggs and Stratton I'm working on has the crank case breather hose cut, and an external cone shaped crank case breather filter installed.

I find it hard to believe the factory did that, and left the OEM tube laying on the rocker arm cover wide open going into the throat of the carburetor. Basically bypassing the air filter, albeit a tiny amount.

Why would someone do this? My only guess is an issue I've heard with direct injection engines. Carbon and crud buildup on the intake valves due to not having any gasoline to wash it off.

I'm asking because my first inkling was to replace it and make it proper. But, perhaps that's a mistake? Maybe I should just plug the OEM line and leave it vented separately?
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Old 11-17-2018, 08:43:45 PM
dkamp dkamp is offline
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Default Re: Natural Gas Engines in Cold Weather

Quote:
Originally Posted by cjjmw View Post
All of the smaller engines I've been looking at that are available in gasoline, LPG or natural gas all drop in power when used with different fuels.

For example, gasoline seems to give the most power, 2nd is LPG and the lowest output is natural gas.

Is this because the fuel produces less power, or is it because the engines aren't actually designed for the specific fuel?

It seems like the higher octane of LPG should produce more power than gasoline of the engine is setup for it, no?
Propane, Natural Gas, Gasoline, Diesel Fuel, and Ethanol are all combustible fuels, each one has it's own burn properties, and each one has a different mount of ENERGY DENSITY.

Of these, Diesel fuel has the highest energy density per unit of LIQUID volume... followed by gasoline. Going down the scale, there's Propane, then Ethanol, then Natural Gas.

Changing fuels means, very naturally, that the amount of energy you will get burning a given folume of fuel, will change in relation to the energy density of fuel. Let's say you burn wood to heat your home... a soft poplar and hard oak will both burn in your stove, and if you set up the draft properly, and keep both fuels very clean and dry, they'll both get really hot... but the oak will burn much, much longer... because it has more energy density.

Now, ANY liquid fuel you choose, can burn hot, or cold... get the mixture of fuel and air optimized, and they'll burn fast... but a denser fuel's combustion process naturally changes the RATE at which it will burn.

Have you ever reloaded shotgun shells? Let's say you use just ONE type of powder, and on testing, you find that the first few dozen shells of the night, your shells fire consistent, and yield a nice, tight pattern... but as you get into the last few boxes of reloads, they misfire, or they act really 'weak'. it's because the crimp pressure on those last few boxes was getting pretty weak... your arm was getting tired of pulling down the lever... thus, the wad wasn't being compressed tight... and as a result, they didn't 'burn' well.

Rake up a pile of dry leaves, and light them. They burn pretty quick... but if you spread them out a good bit, the fire will be really slow, possibly evey burn out before it takes off.

These examples illustrate how important the fuel and oxygen need to be well mixed, but 'compressed' in order for the 'flame' to propogate through the fuel at an even rate.

Internal combustion engines follow this circumstance INTIMATELY.
--Too little compression causes incomplete, or slow flame speed.
--As combustion occurs, pressure of the expanding gasses (from the heat of the fire) push the remaining UNBURNED mixture tighter, which (if the flame isn't interrupted) results in the burn rate ACCELLERATING... at least, up until a point).
- interruption of the flame is that it 'blows itself out'... same way putting a stick of dynamite on a wellhead fire 'blows out' the fire...

---THERE IS NO OCTANE in PROPANE!!!
Propane is a chemical compound: C3H8.
Octane is C8H18.

The energy density that a fuel offers, is determined by the strength of the chemical bonds broken in the combustion process. One molecule of Propane has 3 carbon bonds to break. A molecule of Octane has 8. Hexane as 6, Pentane has 5. Butane has 4.

Gasoline used to have an 'octane' rating... because gasoline USED to contain the chemical compund OCTANE.

Diesel Fuel contains the chemical compound CETANE.... that's C16H34... that's TWICE the hydrogen-carbonbonds of a molecule of Octane... and a whole lot more than Propane.

An important point to remember, though... is that although Cetain has lots more bonds... it has a much larger molecule... so... you won't be able to fit as many molecules of Cetane in a bucket... as Octane... so it's not a direct relationship in terms of energy-per-bucket (or gallon).

BTW... When you use the term 'regulator' for gaseous fuels... be very specific... there are regulators, then there are Demand Regulators... aka Zero Governors... AKA Negative Pressure Regulators.

DO NOT confuse a 'regulator' with a Demand Regulator... While they are very similar, they are very different, and must NOT be confused. A common regulator has a high pressure on it's inlet side, and 'limits' it's output pressure... and these pressures are ALWAYS HIGHER than ambient pressure.

A Demand Regulator's output is BELOW ambient pressure... it requires VACUUM in order to flow. In order for a Demand Regulator to work properly, it must have not just any vacuum signal (not Manifold Vacuum), but rather, a DEMAND signal- a spud within a venturi... where more airflow through the venturi causes a greater vacuum (regardless of throttle position).

A propane mixer, a SPUD, and an 'auxiliary venturi' all provide a demand-vacuum signal to draw fuel from a Demand Regulator.

IF you see a 'regulator' device that has option for running engine coolant, or exhaust heat through, that means the device has an EVAPORATOR in it... and it will have either integral to it, or immediately before it... a FIRST STAGE regulator- it takes whatever tank pressure exists (anywhere from nothing, to over 250psi or so) and reduce it to either 10psi, or 2psi. After the fuel has been heated, it will evaporate and build enough pressure to flow on it's own.

Prior note about propane not flowing below -20F... it's more like -43F... but it develops very LOW flow pressures below -20F... but this is not a difficult problem to solve for those who understand phase change of liquids...

Get a can of STERNO and a coathanger. Bend the coathanger into a shape that will suspend the STERNO can below the tank by about six inches, and light the STERNO. it'll warm the fuel enough to bring tank pressure up right away...
...and before anyone comments on how this will become tragic...
Propane, at atmospheric pressure and in liquid form, is an INFINITE heat sink. It requires heat MUCH MORE intense than a STERNO can to even slightly warm the propane tank. Remember: If you have a hopper-cooled hit-and-miss engine, that engine will NEVER, EVER exceed 212F as long as there's LIQUID WATER in the hopper. ;-)
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Old 11-18-2018, 01:35:21 PM
cornbinder89 cornbinder89 is offline
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Default Re: Natural Gas Engines in Cold Weather

You are taking thing too literally. Octane (and I put in quotes) has been a rating and not actual octane for years, you couldn't have gas higher than 100 otherwise.
At -23 there isn't enough tank pressure to keep a liquid draw system fed. true, pure propane liquid point at atmospheric is around -44 F but not all LP is pure propane, and for practical purpose running an engine off of LP at temps much below 0 f is going to be difficult unless heat is provided to the storage tank, as soon as liquid is drawn off, the pressure drops and it takes heat to restore the tank pressure to where you started.
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Old 11-19-2018, 03:08:59 PM
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Default Re: Natural Gas Engines in Cold Weather

I think the confusion is that people often mix up octane and anti-knock rating. For gasoline, octane is resistant to knocking and so it is used as the standard for a fuel's antiknock resistance. That's why even though pump gas is 87 or 89 octane by the (R+M)/2 method, it is possible to produce engineered fuels with octane ratings above 100- that is to say an engineered fuel formula that is more resistant to knocking than 100% octane is.

Ethanol, Propane, and Natural Gas all have higher knock resistances than gasoline, and so would show favorable 'octane' ratings if tested. But they do not actually contain any octane, leading to confusion if they were rated in this way.

Because of that higher knock resistance, you could mill the deck on the engine or put in a stroker crankshaft to increase the compression ratio and gain a higher fuel efficiency, as well as offsetting some of the loss of power that comes from using the less dense fuel. But most of the time this additional machine work was not done, and the engine is just a regular gasoline construction with the carburetor replaced with the necessary equipment for the alternative fuel.

Quote:
Originally Posted by dkamp View Post
Let's say you burn wood to heat your home... a soft poplar and hard oak will both burn in your stove, and if you set up the draft properly, and keep both fuels very clean and dry, they'll both get really hot... but the oak will burn much, much longer... because it has more energy density.
Soft wood actually has slightly more energy in it than hard wood does, 9050 btu/lb vs 8600 btu/lb. But that energy is released faster, too fast to be desirable for heating your house where long slow release is desired. On the other hand in a boiler or in a kiln, soft wood is actually preferable as a fuel because it will give up its energy quickly and get out of the way to make room for more fuel to be added.


Quote:
Originally Posted by dkamp View Post
Internal combustion engines follow this circumstance INTIMATELY.
--Too little compression causes incomplete, or slow flame speed.
--As combustion occurs, pressure of the expanding gasses (from the heat of the fire) push the remaining UNBURNED mixture tighter, which (if the flame isn't interrupted) results in the burn rate ACCELLERATING... at least, up until a point).
- interruption of the flame is that it 'blows itself out'... same way putting a stick of dynamite on a wellhead fire 'blows out' the fire...
The density of the charge has a drastic effect on the flame velocity, as well as the fuel's own properties. As the flame starts to spread through the fuel the temperature and pressure of the charge rises, and if it gets high enough fast enough the remaining unignited charge will ignite all at once by compression-ignition, resulting in knocking damage.

Flame front velocity determines how fast the burn spreads outside of a knocking situation, and is important for setting an engine's timing. Propane in particular not only has a narrower ignitable mix range than gasoline, but the flame front velocity is lower. An engine using propane isn't as likely to knock because the propane doesn't burn as quickly, but also needs a little more spark advance to compensate for the slower burn.


Quote:
Originally Posted by dkamp View Post
BTW... When you use the term 'regulator' for gaseous fuels... be very specific... there are regulators, then there are Demand Regulators... aka Zero Governors... AKA Negative Pressure Regulators.

DO NOT confuse a 'regulator' with a Demand Regulator... While they are very similar, they are very different, and must NOT be confused. A common regulator has a high pressure on it's inlet side, and 'limits' it's output pressure... and these pressures are ALWAYS HIGHER than ambient pressure.

A Demand Regulator's output is BELOW ambient pressure... it requires VACUUM in order to flow. In order for a Demand Regulator to work properly, it must have not just any vacuum signal (not Manifold Vacuum), but rather, a DEMAND signal- a spud within a venturi... where more airflow through the venturi causes a greater vacuum (regardless of throttle position).

A propane mixer, a SPUD, and an 'auxiliary venturi' all provide a demand-vacuum signal to draw fuel from a Demand Regulator.
Demand regulators are still regulators- they measure the downstream pressure, and adjust flow through themselves to maintain the intended setpoint.

The biggest functional difference is that a demand regulator has a setpoint measured in inches of vacuum instead of pounds pressure. And the mechanism involved in actuating the valve is built differently to reflect that.


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Originally Posted by dkamp View Post
IF you see a 'regulator' device that has option for running engine coolant, or exhaust heat through, that means the device has an EVAPORATOR in it... and it will have either integral to it, or immediately before it... a FIRST STAGE regulator- it takes whatever tank pressure exists (anywhere from nothing, to over 250psi or so) and reduce it to either 10psi, or 2psi. After the fuel has been heated, it will evaporate and build enough pressure to flow on it's own.
LPG at tank pressure exists as a liquid at its boiling point in contact with pressurized vapor. If you lower the pressure in a 1st stage regulator, the liquid is going to become a gas immeadiately, at risk of icing up the regulator. Thus, the Impco regulators I've changed the diaphrams in did not appear to have a 1st stage in them. The liquid propane from the tank entered a passage close to the water jacket, and a needle valve moved by the diaphram directly metered the tank-pressure liquid into the evaporation space. I could see a larger regulator needing to be 2 stage, but both stages would have to be heated.


Quote:
Originally Posted by dkamp View Post
...and before anyone comments on how this will become tragic...
Propane, at atmospheric pressure and in liquid form, is an INFINITE heat sink. It requires heat MUCH MORE intense than a STERNO can to even slightly warm the propane tank. Remember: If you have a hopper-cooled hit-and-miss engine, that engine will NEVER, EVER exceed 212F as long as there's LIQUID WATER in the hopper. ;-)
I'd be more worried about the open flame igniting any leaks than I would about a sterno cup triggering any sort of BLEV explosion.
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Default Re: Natural Gas Engines in Cold Weather

Are there any pros or cons of using a demand regulator vs other methods of regulation?
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