Author Topic: field marshal with gas connection  (Read 416 times)

saba

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field marshal with gas connection
« on: October 21, 2018, 11:19:34 PM »
https://www.youtube.com/watch?v=qReu9PuP4yQ

actually i tried it myself works perfect..

38ac

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Re: field marshal with gas connection
« Reply #1 on: October 23, 2018, 12:06:49 PM »
Nice to see somebody starting one that actually knows what they are doing, lube on the crankshaft prevents the handle from sticking. It's much easier to turn it backwards to get the decomp set rather than forward.  Have the fuel turned on before you start cranking.
Watching You Tube videos of people starting CS engines is both appalling and entertaining. Seen people start them and leave the crank handle on the shaft. Seen people struggle to pull them over compression because they didn't know to use the release. Seen the racks stuck open and the engine running stupid fast RPMS. Seen people leave the rack closed and have to play speedy Gonzales to get the decomp off and rack open,,,,

It doesn't take a manual to figure that stuff out, just common sense which that operator obviously has.
Collector and horder of about anything diesel

mike90045

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Re: field marshal with gas connection
« Reply #2 on: October 23, 2018, 09:45:49 PM »
There is a de-compresser ?    (just kidding)

glort

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Re: field marshal with gas connection
« Reply #3 on: October 24, 2018, 12:34:42 AM »

I was watching a vid yesterday by a long time biogas advocate.
It was painful. A real amateur hour with any comedy replaced by cringe worthy fo pars and misinformation.  Guy has been doing boigas vids for about 10 years now and shows building Digesters and " converting" engines.

This fella is using petrol engines and just sticking a hose in the airbox with no form of regulation at all. because he uses a gas bag and a small Diameter hose, he has come up with the brilliant Idea of using a high powered aquarium pump to shove the gas into the engine fast enough to let it run.
because there is no power to pump the gas to make the engine run on startup, he starts on petrol then turns on the gas and turns off the petrol.

The engine sits there barely running and coughs along because the guy is too dam stupid to wait till the thing starts running out of fuel before turning on the gas.  It's painful to watch.
The guy hold himself out as an authority on this kind of thing and announces himself as being from a .com website which is more of a shrine to massaging his own ego than anything else.

He demonstrates the gas powered generator which looks to be about a 5KW size powering a small lamp. I can only imagine the laughable results if he tried to plug in and  power 1 1KW load let alone anything bigger. The real sad part about this is he titles the Video as a how to for hurricane situations.
Someone is going to be very disappointing following his laughably flawed advise.
He professes biogas as a fuel you will always have if you have food or human waste to feed a digester with.  Being in the US, even those with the most basic knowledge on the subject would know they need to be kept at or above 25oC as an ABSOLUTE minimum to produce any gas at all.  being that so much of the US has Snow and temps below 25 for a good part of the year, again the claim and implications are completely wrong.


The one thing that does come from this arseclowns Vids is how much gas you need to power an engine.  Obviously compressed gas such as LPG is different but if one were running Biogas which is only compressed to 100 PSI max, you are going to need a lot of bottles to run any decent time.
A diesel is ideal for this sort of Supplementary fueling though because it has it's own regulation built in. Diesel will make up any short fall in gas and keep the thing running fine.

I find that using a waste oil is a far easier, cheaper and energy dense fuel but if supplies of liquid fuel are limited and you have or caqn get hold of some gas ( as in vapor type gas) then this really makes a Diesel a true multi fuel engine.

ajaffa1

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Re: field marshal with gas connection
« Reply #4 on: October 24, 2018, 12:08:47 PM »
Hey Glort, I`m wondering about the advantages of adding a gaseous hydrocarbon to a diesel engine, doubt it would auto combust under pressure like diesel, WVO or WMO. Would it have a faster burn rate that would improve efficiency? Perhaps it would be OK in a hot cylinder that had been started on another fuel.

The video doesn`t appear to show a glow plug to assist combustion so I have to assume that bio gas will ignite at around 20 to 1 compression. Food for thought for anyone trying to compress it for storage, any amount or oxygen contamination could be catastrophic.

Bob


glort

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Re: field marshal with gas connection
« Reply #5 on: October 24, 2018, 01:10:27 PM »

From what I have read Bob, for this to work properly you need the Diesel injection to set off the gas.  If you don't have that, you have to put a plug and coil on the engine which makes it an SI not a diesel any longer.
I would guess the Gas would light off under compression but being in the cylinder during compression rather than being injected towards the end of compression, I imagine would make it the perfect example of uncontrolled detonation as it would be lighting off when it wanted, not when you wanted it to in the Cycle.

Having the engine still injecting diesel means with sufficient gas the thing is at idle fueling so is going to be using as next to no diesel fuel as can be.

It's a long time since I looked into gas. I know it has a higher octane than petrol, I'd imagine a lower cetane as it were than Diesel but I can't remember what the flame speed relativity is but I have a feeling its faster than diesel.  It has less energy but will tolerate much higher compression ratios than Petrol. It has less energy per pound so is best used with turbo engines where more gas mixture can be rammed in with vehicle applications.

Fumigation used to be popular with diesels for economy and performance but the long term results of that were not good.  Not many people are still game to sell or fit these systems now especially on modern light weight/ high speed computer controlled diesel engines.

Gas burns a lot cleaner than Petrol or diesel as well as being a lot Drier which can make it real hard on valve seats.  Running waste oils with gas would be a perfect combination due to the oil burning dirtier and giving the valve seats some lube and cushioning.
  I would definitely put an oil or lube of some sort in diesel if I were running it with gas.


Johndoh

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Re: field marshal with gas connection
« Reply #6 on: October 24, 2018, 04:05:36 PM »
I take it this engine is unregulated? Big load and it dies?
It is better to light a candle than to curse the darkness

BruceM

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Re: field marshal with gas connection
« Reply #7 on: October 24, 2018, 04:37:43 PM »
Like CarlB's setup, with a fixed NG flow, when a big load hits, more diesel is burned.  The NG-diesel mix can't go over about 85% NG. 

Propane-diesel is disappointing, about 20% max.


glort

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Re: field marshal with gas connection
« Reply #8 on: October 25, 2018, 01:13:25 AM »
Propane-diesel is disappointing, about 20% max.

Is that due to the propane detonating?

From memory Propane has more energy than NG and Methane has less energy again. Maybe the propane is too energy dense and easy to light off to use in higher concentrations.  I am surprised though. I would have thought you could have fueled it up the same as any other gas.

BruceM

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Re: field marshal with gas connection
« Reply #9 on: October 25, 2018, 03:24:44 AM »
You're right, Glort, Propane detonates at much lower pressure.  On my neighbor's 8/1 propane conversion (with long reach spark plug in the former injector hole) we had to add almost 0.6 inches (0.5 inch aluminum plus some 0.032 aluminum) under the cylinder to prevent pre-ignition under load. Push rods had to be extended.

mikenash

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Re: field marshal with gas connection
« Reply #10 on: October 25, 2018, 07:35:47 AM »
30-odd years ago when our government still ran the dairy industry and we had LPG so cheap and plentiful we were burning the stuff off to get rid of it we trial-converted some Isuzu tractor units to run on diesel/LPG.  They were towing semi-trailers full of milk from collection points to processing plants.  By chance I later worked with one of the drivers and he said they had heaps more torque - overtake everything up the hills - but the project was abandoned because, regardless of configuration, sooner or later the engines just cracked pistons . . .

saba

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Re: field marshal with gas connection
« Reply #11 on: October 25, 2018, 10:50:51 PM »
My experiance with NG propane and liquid petrolium gas LPG, I started with LPG that I used on my boat for cooking, it's a mix of propane and butane, the propane boils of first from the bottle and your left with butane wich self egnites in the compresion so your "dieselknock"will be a lot louder. Propane is a dream aswell as natural gas. It has high properties.

I put a lot of googeling time into it before I first tried, I even read articals that in the us they use it in trucks as bifuel to increase power and better fuel economics. Most of the stuff I allready forgot again but I remember it was clear green light.
Only like I said butane, in winter time in Holland they incease the amount of propane in lpg because of the difference of boiling points of the gasses so maybe then it's ok to use it in a diesel.
As I remeber there are even companies in europe holland that can install it in a diesel car for an increase of fuel economy.

I never automated the gas supply so I did not dare to leave it alone, but for sure it worked.I just used it when I was near the engine and whenever I left just close the tap and it would run on wvo the rest of the time. My intention was for a cleaner burning so my exhaust gas cooler would not faul so fast and a lack of supply of wvo was looking for an alternative.

Bernhard

glort

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Re: field marshal with gas connection
« Reply #12 on: October 25, 2018, 11:58:13 PM »

 I started with LPG that I used on my boat for cooking, it's a mix of propane and butane, the propane boils of first from the bottle and your left with butane 

I'm pretty sure that does not happen. 
LPG can be propane, Butane or a mix of Butane and propane in somewhat varying qtys. The 2 gasses  vapourise together as their properties are such that it is not possible for on to vaporise and not take the other with it.

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I even read articals that in the us they use it in trucks as bifuel to increase power and better fuel economics. Most of the stuff I allready forgot again but I remember it was clear green light.

Given that it's the only fuel we are self sufficient in here, there was a lot of work and conversions done with it on out Vehicle fleet also.
While it does give better power than diesel and is cheaper, the long term effects on Diesel engines were highly detrimental.  Anything that had fumigation also had a markedly shorter life to engine running on Diesel alone.  They was evident from everything to from 4WD's to road trains.

Conversion was a boom industry some years back but now there are very few doing it and no one other than those selling it recommending it.

Perhaps the problems were related to what Bruce pointed out earlier, the ratio.  From what I remember the vehicles being set up with fumigation were pumping a LOT more than 20% of the stuff in.  20% for one thing would not have meant enough cost savings to make the conversion exercise worthwhile for a start.

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As I remeber there are even companies in europe holland that can install it in a diesel car for an increase of fuel economy. Perhaps they have not heard of the experience else where which I find hard to believe which leave the likley option of they don't care and are just trying to make a buck.  Would be interesting to see what the warranty terms were with respect to damage to the engine.  Even if there is one, I bet that everything else from engine manufacturing faults to the price of Sturgeon in Vladivostok would be blamed for any issues and the owner would be facing an impossible task to get compensation. 


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I just used it when I was near the engine and whenever I left just close the tap and it would run on wvo the rest of the time.

I wonder what the long term effect on slow speed Diesels like listers is if any? It would seem the knocking may be due to too much Gas rather than the gas mix. I have been playing with Biogas and reading up on that  of late. It has a lot going for it in the way of simple and cheap to produce but for running an engine for any time, the energy density is such that to be practical you need a farm with animals for the manure as feed stock, the space to build a Huge digester, a tropicaly warm climate all year round and a very large indoor area to house the gas storage.
The amount of gas used in cooking is one thing, the amount to run an engine is another. Plenty of people doing it on farms in india and even in the states where it snows but the latter is a high dollar, Hi tech commercial operation rather than a backyard setup.

Crunching the numbers yesterday, I worked out I'd have to completely fill the space of my extended 3 Bay high roof garage to be able to run a 5 KW generator for a day off biogas. And of course have enough bags to hold said gas volume. The digester i'd want to be practical and would not keep up anyway would have to be 5000L at least and the feed stock would be hundreds of Kilos of manure and water a day.  If you have a dairy, chicken farm or Piggery, Perfect! You have the manure and water to start but otherwise... Food scraps from the table are not going to cut it.

Hydrogen could also be a possible alternative gas.  Then again if you have the electricity to create it in the first place, probably better to stick to that.
I'm always amused when I see something on TV or the net where they show an engine running on Alcohol, a gas or any other flammable liquid like it's some sort of Miracle.  If it's combustible, only thing is getting the mixture right. Nothing else is a surprise.

The other gas people play with for running engines is wood gas. Seems way too complicated and effort intensive as well as unreliable for my liking.
Again, processing the feedstock in sufficent qty to run a generator would make the idea impractical for most unless you had some sort of suitable waste product from another industry.

 
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My intention was for a cleaner burning so my exhaust gas cooler would not faul so fast and a lack of supply of wvo was looking for an alternative.

Water injection into either the engine or the exhaust will keep things clean.
If you are running short of WVO, Used engine oil may be another alternative for you.  There is nothing to beat the energy density of liquid fuels let alone the ease of preparation to make them suitable as a fuel.


saba

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Re: field marshal with gas connection
« Reply #13 on: October 26, 2018, 01:49:54 AM »
Hey glort I knew you would dive in, the gas thing was just out of interest and the fact when I store my boat in winter I need to take the bottle out for insurance reasons.  So engine + bottle....

If I would use the bottle sometimes I would use a torch on the bottle to get the gas out, it would freeze.  (sounds more dramatic then it is). Not bullshitting propane and butane have verry different boiling points, to lazy to look it up again but butane beeing someting like 10 degr celcius. So if in cold weather your draining the bottle....Thats why in summer you have a load more butane like 30%. You can find it somewhere on internet.
But the last bit of the bottle was not nice to run it really started to knock badly.

With the natural gas the economic reason is not there in my case almost same price, but I used it and it worked only I should increase flow, was like 10 % of the load.



I know one point your very keen on the water injection, if you burn fuel you got a lot of water aswell  hydrocarbons...with gas I believe its even more. I was condensing the exhaust gas so I already got liters of water draining from the heatexchanger and when the boiler reached it's temperature the condensing would happen somewhere further down the line making a mess.
I'll promise that when I start the plant up again I will give it a try with extra water but for the exhaustgas heat exchanger I do not see the advantage (yet). Promise one day I will try.

For the last years I put to much time in my chp plant I need to catch up with some other stuff I still work and just bought some garage that I am busy with.I love this stuff so it will start again.
Bernhard

Matt12

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Re: field marshal with gas connection
« Reply #14 on: October 26, 2018, 02:05:14 AM »
Hey glort I knew you would dive in, the gas thing was just out of interest and the fact when I store my boat in winter I need to take the bottle out for insurance reasons.  So engine + bottle....

If I would use the bottle sometimes I would use a torch on the bottle to get the gas out, it would freeze.  (sounds more dramatic then it is). Not bullshitting propane and butane have verry different boiling points, to lazy to look it up again but butane beeing someting like 10 degr celcius. So if in cold weather your draining the bottle....Thats why in summer you have a load more butane like 30%. You can find it somewhere on internet.
But the last bit of the bottle was not nice to run it really started to knock badly.

With the natural gas the economic reason is not there in my case almost same price, but I used it and it worked only I should increase flow, was like 10 % of the load.



I know one point your very keen on the water injection, if you burn fuel you got a lot of water aswell  hydrocarbons...with gas I believe its even more. I was condensing the exhaust gas so I already got liters of water draining from the heatexchanger and when the boiler reached it's temperature the condensing would happen somewhere further down the line making a mess.
I'll promise that when I start the plant up again I will give it a try with extra water but for the exhaustgas heat exchanger I do not see the advantage (yet). Promise one day I will try.

For the last years I put to much time in my chp plant I need to catch up with some other stuff I still work and just bought some garage that I am busy with.I love this stuff so it will start again.
Bernhard

Hi Saba,
             You are correct about the two liquid gases evaporating at different rates, butane boils at about 0deg c, so it is last to leave the bottle, the two liquids are mixtures, not solutions and have very little 'polar' bonding of the molecules, as evidenced by your observation of the knocking that occurs during the last of the cylinder's contents, if they didn't boil at different rates, refinery distillation columns wouldn't work.
Matt12.