Lister Engine Forum
Lister Engines => Listeroid Engines => Topic started by: dkmc on November 24, 2006, 03:58:28 AM
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Has anyone here experimented with using propane or Nat Gas as a primary fuel in a Listeroid?
I have seen it done with a VW Diesel in a lab. The Diesel injection is used to ignite the Nat Gas, but the engine runs mainly on Nat Gas, or somewhere upwards of 60% Gaseous fuel with 40% Diesel used for ignition and upper cylinder lubrication.
Increased power with little or no additional noise, and some increased temperature.
In my application, for the winter months, Natural Gas is most likely the lowest cost fuel I could use. (WVO is not free, and depending on what your time is worth, maybe not even cost effective). My application would be to use Nat Gas to turn a generator before scavenging the heat for building heating. With no demand charges on Nat Gas (YET!) it makes sense to use the energy to turn a generator instead of sending it directly to a furnace.
I am in need of any information members might have regarding Gaseous fuel injection into a Listeroid engine.
The increased temperature might well be a plus for heat scavenging.
Any thoughts? :-\
Dan K
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Hi In my opinion propane could be injected in a diesel through the inj pump, But!
1. a diesel injecter pump would leak. Probably. Probably would have to be a custom made item.
The nozzle would have to be designed to not leak under pressure untill the pressure rose enough to inject( higher than the saturated pressure of propane.)
2. Lubricant would have to be added continuously. I think it would settle out of the propane in the tank.
Much better to add the propane through a gas carb linked to the governor rack.
Dennis
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' Much better to add the propane through a gas carb linked to the governor rack.'
Agreed. Mostly....
Running anything other than liquid fuel oil, WVO, etc thru the injection pump is not an option.
Will not work, and not required anyway.
There is little if any lubricant in propane, and nothing to settle out of it in the tank.
Nat Gas has NO lubricating qualities, and thats harder on any engine, which raises life expectancy questions.
How to get the gaseous fuel in the engine is not an issue.
How the engine (Listeroid) behaves on said fuel is the question.
dk
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Hi
Natural gas and propane engines generally last much longer due to clean burn.
I thought the injecters would need lube. Thats why i suggested extra lube in the fuel.
Other posts in the recent past have suggested gas fumigation is viable.
Somebody has to try it.
One story I read about a pickup truck with manual propane control worked well. I think under a steady load manual control through a regulater should work fine.
Just do it
Dennis
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How would one govern such a thing? If the injector is just acting as an igniter, wouldn't that turn it into a hit or miss engine if you relied on the stock governing system?
Bill
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Hi As I understand the process, the rack is still governed by the speed Just like the load was reduced. The gas takes part of the load.
In a NA diesel you won't be able to add much gas before you get missfiring.
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Why wouldn't you fix the rack position at a low level - just enough to keep the engine running at a very slow idle. Then rig the governor lingage to somehow control the gas flow?
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I think thats a good idea Jim.
Perhaps a separate governor for the gas carb would be best.
I suppose modern electronics could be employed to govern engine speed also.
Then there is the question of actually adding a spark plug and ignition coil to
make the engine true spark ignition......dual fuel perhaps.
But I like the DI approach the best.
Just wondering of any ill effects from increased heat and firing pressure on the Lister design, although the massive bearing area
and general robustness of the castings may make it a moot point. Valves and guides may suffer from the effects of Nat Gas the most.
I need an engine to experiment with!!
dk
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You dont want to use a carb, just a nozzle with a regulator and valve to vary the amount that injects it into the intake stream. The carb would limit the oxygen pulled in and therefore cause problems with the diesel burning(Ie to rich). Natural gas and propane injected in this manner would not cause any problems with increased heat or pressure. In a spark engine they limit the oxygen to burn it lean to decrease emmisions and that can cause problems. In a diesel there is no problems with this as there is no restrictions in the intake stream. All hydrocarbon fuels have close to the same energy "per pound" and as a result there is no issues of gaseous fuels having increased heat or higher firing pressure than diesel fuel.
With a regulator/valve setup you just increase the gas fuel when the engine is running at its lowest load. As you increase the amount of gas the diesel injection rack will start to close. Increase the gas until the point that the engine starts to run rough and then back off the gas a little so it runs smooth. Leave the gas at that point and the governor/injection pump will self adjust to increasing load.
I would be afraid of locking the injection pump into one position and adusting the gas flow. If the engine for some reason started to run away and you had to fumble with the injection pump lock to shut it down it might be too late. If the injection pump is closed all the way even if the gas fuel is still flowing the engine will shut down as there is no form of ignition.
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I believe there are some experimental airport shuttle buses with diesel/propane fueling. The diesel is just for ign and the propane is for the actual power produced. It results in a very clean diesel engine.
I think the above post is correct. The diesel inj pump remains at or around the idle setting. The propane is injected into the intake manifold in varying quantities to adjust power and rpm.
However, with nat gas furnaces around 80++% efficient, I think your best money is still to use nat gas as heat only. You will have to do some quality engineering to achieve that level of overall efficiency.
Honda builds or built a conbined cycle unit with 90% efficiency. It runs on nat gas, generates electrical power and makes heat. If they can do it on a production basis, you can do it on a one off basis.
Chris
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This is all off the cuff, guesstimate, feels about right, experimentation. Do NOT try this at home.
I had all the parts, so just for the hell of it I rigged up a little propane tank to my engine yesterday. Maybe I'll refine it, maybe not, maybe I won't have a need to use it at all.
I adjust it by opening the valve a little bit to the point that if I remove the hose the engine reacts like I applied a 500 or so watt load. If I attach a fitting to the hose at that adjustment and light it I get a 4 or 5" yellow flame. The valve is barely open. Just like I've heard the rack closes as gas is increased.
After about 5 hours of running (4.5 on WVO) my IDI chamber had less carbon than when I started and was for the most part carbon free. It had a very light layer of carbon that was more like soot when I started. If I go with this I'll just use a 1 lb. bottle every few hundred hours (to be adjusted as needed) to get rid of the carbon. I want to burn as much WVO as possible and I don't want to clean the head if I can avoid it. The engine sounds the same with the propane on or off.
(http://www.genedevera.com/temp/propane.jpg)
http://www.genedevera.com/listeroid/#engineroom
Thanks, Geno
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Well, it would be nice if I actually got email notification of responses on this thread, but most of these forum sites aren't very good about that.
Just checked back here and am amazed at these responses!
BIG big thanks to Geno for the experimentation and report !
Makes sense that the rack would close down with the added gaseous fuel.....and how handy that it 'regulates itself' in that way!
Geno, I wonder if there would be -any- sign of increased heating under full load conditions...?
Firebrick is absolutely correct, no throttle plates allowed in the intake on a diesel.
I wonder if a venturi would help mix the gas for even distribution.......maybe at least a spray bar with a series of small holes to assure
even mixing of gas/air....?? I admit I like electronics for engine monitoring/ control, so the idea of an electronic governor and fuel 'injection'
system seems interesting to me.
Cujet: I think your best money is still to use nat gas as heat only. You will have to do some quality engineering to achieve that level of overall efficiency.
Here is the punchline to my proposal......
Here in Upstate New York, at my shop, 3 phase electric is very expensive.
When I divide my monthly electric charges by killowatt hours, it comes out to around .22-.24 cents -per- KWH....!
We are taxed to death on utilities, and the demand charges are a form of legal highway robbery...
Although my shop is small, and there are no demand charges if I am below 5KW, it always works out that the bill reads 5.2 or 5.3KW demand minimum. Go figure....
With electric rates in these ranges, I think it is well worth considering the generation of power on site, with waste heat as a 'free' by product....
The full payback on the project may only be 3 or 4 years.....?
If I'm mistaken, please tell me why.....
thanks for your info guys!
dan k
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Hi With 3ph charges the way they are I would certainly get 3ph gen head.
Just to run the shop equipment. A plus would be to run your house loads.
Dennis
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Water injection would increase power and clean the carbon deposits also.
Stan
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water injection will clean the engine quite well, but won't increase power.
water injection usually can increase power in spark engines by allowing advanced timing
something to keep in mind is water vapor displaces oxygen which cuts power output in most cases, but not by much
i suppose it is like everything, a comprimise, you give up a touch of power to have a clean engine. not a bad trade off in my opinion for the vast
majority of folks
a diesel running in dual fuel mode (diesel pilot and gaseous primary fuel) will exhibit a reduction in power output, how much of a reduction depends on the ratio of gaseous to diesel and maintain a stable running engine (probably in the neighborhood of 75/25). the engine will not run hotter under load because of the decrease in the overall btu average of the two fuels being lower than that of running on straight diesel.
i know if i was you, i would be looking to find an ST 3 phase head, and would have it setup to power the shop for at least the 3 phase loads
bob g
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"i know if i was you, i would be looking to find an ST 3 phase head, and would have it setup to power the shop for at least the 3 phase loads"
Yes, and I have an older Warner Swazey 30KVA single bearing altenator. Plus the auto-transfer switch and fully instrumented control panel for it.
It had a 505? 507? Continental 6cyl on it that was backfired and jumped time......I scraped the engine. I'd like to find a 24/2 to run it.
Problem is, I have a few CNC machines, and am concerned about regulation and reliability for running the computer controls.....
I probably need a max of 20KW surge....
Can you suggest a supplier of -good- engines that is in the NYS area, or closest for shipping purposes?
Any used 24/2's out there??
With the generator, controls, and enough assorted hardware lying around, I'm probably wasting time thinking about the economics of the project.
I might be best off doing it and starting the savings for winter 06.......? The Nat Gas supply and controls for that are a mystery to me.
I know I can't just 'run a hose'.....! ;D Where would a guy go to collect the parts for the Nat Gas or Propane equipment required?
Any owners nearby?
I did correspond with a fellow in the Geneva, NY area a couple years ago......
I'll post separately.....
Thanks again for the info...!
dan k
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Dan K
What are your 3 phase motors running and how big are they?
One solution is to run the equipment off of the listeroid complete. Many old machinery shops had a jackshaft over head or down one wall that ran all the lathes/ and drill presses off of belts. They were tensioned to engage the individual machines. Belt drive in this manner is much more efficent than converting mechanical energy into electricity and back again. I think belts loose somewhere less than 5 percent compared to 20-30 percent for a generator loss(this is just off memory so maybe doug or someone else could help?) Of course this limits you machine layout and if you have small kids or idiot adults around there is somewhat of a safety issue depending on how you do it. The other option, if you 3 phase motors are not to big, is to build a phase converter. They are simple to cobble up but they dont work well as well for large hp electric motors. Again, I do not know what you are running so these are just general suggestions.
As for the nozzle to inject propane. The best thing I have seen to do it is a Cat either nozzle. It is a 2.5 inch long small diameter brass tube with very fine holes drilled in the sides all over and capped at the end. At the other end is 1/4 inch pipe threads so the hole shebang can be installed very easy into any intake plenum buy drilling and tapping a 1/4 inch NPT hole. The nozzle has a small flared male connector on the outside for a secure leak free connection to tubing. If it can mist either fine enough I am sure that propane would be no problem. I am sure other brands have them as well.
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The Nat Gas supply and controls for that are a mystery to me. I know I can't just 'run a hose'.....! ;D Where would a guy go to collect the parts for the Nat Gas or Propane equipment required?
For natural gas you will need some or all of the following, depending on what you do exactly. For carburetion you need a shutoff, otherwise gas will trickle from the carb when the engine's not running. Most of these are 12V, but if you have a good memory I guess you could use a manual shutoff too. I don't recommend it. There's a problem with shutoffs in that it's hard to know when they've failed. I've heard that some localities require two shutoffs with a pressure switch inbetween to allow testing.
The carburetor has two parts. First, a mixer, which is a venturi with a membrane and armature that opens a valve more and more as a vacuum builds up in the venturi. Second the throttle body sits under the mixer, and contains a butterfly valve to let more or less air in. This can be mechanical, or some places like Woodward sell electronic ones that work in conjunction with a governor. If you buy a governor then you will also need and MPU or magnetic pickup which tells the governor how fast the flywheel is turning.
Regulators establish a baseline pressure at the carb's intake. You can typically adjust this up or down a bit to suit your application. If you're using compressed gas you will need an auxiliary device that prevents the regulator from icing up.
Impco is a well-known supplier of this equipment. They have PDF's on their website for the capacities of the various parts. You will want a 55 series carb as these go to 70hp and 115cfm. Woodward has exactly the same mixers as Impco, but with different names. There are some other manufacturers as well but I can't think of the names at the moment.
This equipment is sometimes available at your local propane shop, 4x4 shops (offroaders like propane because they can go at any angle without emptying their carb bowls), forklift shops, and of course Ebay.
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There are quite a number of natural gas setups that run on Lister HR2 and HR3 machines (and many others) in the oil patch. The engines use a completely different concave piston design and have a spark igniter added in place of the injector in the head. Anyway, there are parts available from these setups in the Canadian and US oil-patch areas that may provide useful parts for tinkering with. I have some experience with Gasoline/Propane conversions but not Diesel/Propane in the ways suggested on this forum. I do know that engine deposits are greatly reduced but at the same time exhaust valve heating becomes an issue so mixture and timing becomes critical to avoid valve and valve seat failures from overheating.
Gary
diesel-electric.us
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I do know that engine deposits are greatly reduced but at the same time exhaust valve heating becomes an issue so mixture and timing becomes critical to avoid valve and valve seat failures from overheating.
This is quite correct on spark ignition engines, especially in the gas fields because some of the fuel can vary in energy pretty rapidly. Because of this you can go from lean to rich and or vice versa pretty quickly. Some of your bigger and more expensive engines have woodward controls that check for detonation and vary the gas mixture and timing to keep this from happening. This is less to a non problem on the supply side of natural gas because it has been processed and mixed sufficiently to even out its energy content.
However when using it in a diesel these problems dont exsist. Because they diesels draw in a full air charge every time they dont burn lean unless at one very specific load. But remember you are only supplanting part of the fuel charge. As the load increases there should be a optimum fuel ratio spot and as it goes beond that it becomes richer as the injection pumps more fuel in even though more air can not enter resulting in black smoke resulting in a rich mixture. Unless you rig up some type of complicated injection metering system for the gaseous fuel, one should set the gas amount at small load, because if you set it at a higher load and that load drops, the rack will close on the diesel injection pump and the engine will not burn the gaseous fuel possibly shutting down the engine or causing flames to shoot out the exhaust when it opens again. If you rig up a varible gas injection system you would really need to pay attention to burning lean but I dont think that anyone here would do such a thing as it would take more money for the controlls than the engine cost