Lister Engine Forum
Slow Speed Diesel Engines => Changfa Engines => Topic started by: guest22972 on June 17, 2019, 01:18:48 PM
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Removed at user's request
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Man ! those are beauties !
I am GREEN with envy.
Those engines are of superior quality and should outlive you if cared for.
Nice acquisition.!
Keep us posted of your project.
Veggie
PS: AU law prohibits the possession of more that one Kubota RT series engine.
I would be happy to take one off your hands in order to help keep you within the law :police:
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Great bargain finds, Glort. If you have enough room for all those panels, you'll have to start a business that needs lots of power during the day! Generating and compressing hydrogen???
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Well done mate, we need pictures. By the way did you ever collect that other engine i put you on to, out west?
Good news on the panels, i have a whole lot if you want.
Our energy company just changed hands, and today they just installed our two new smart meters. Don't that suck.
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Winter overcast/clouds is an issue for PV planning In my sunny climate, and home designed for minimal power use, it's easy to add enough panels to fully charge the batteries every day, even on cloudy days. With 2350 watts I never run the generator to charge batteries anymore, I don't even have the charger hooked up. I just avoid electric cooking on dark winter days, and only do laundry and water pumping when it's sunny. Our winters are darker now, but still, 4 days of heavy clouds happens only once or twice a winter.
I read an article on a Budist retreat center in nothern Canada that was off grid; they added LOTS of near vertical PV for winter, so that even when overcast, they could make their daily power nut for the batteries, saving a bundle in genny fuel (and noise). You do get power when it's anything but dark, but you may need 5x or more the area in panels.
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Hi Glort, it is very difficult for me to politely express how much I hate you right now. I have been looking for one of those for over two years with a budget of $1,000 and you score two for that price! Shame on you. :laugh:
It will be very interesting to see how many alternators it takes to bog down these beauties. When are you planning to start your own power company so you can export all this power to the local community?
Grrrrrrrrrrrrr Bob
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Hi Glort, I have recovered very well from my surgery and should be starting some physio therapy next week. Narelle is just coming up to six weeks after her hysterectomy, she has been through hell but is just starting to come good, she still can`t drive or lift anything but we have been walking the dog together and things are looking good.
I`m planning to get back to the ETB rebuild next week, will make a big change from being nurse Bob! :laugh:
Bob
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"My own tests and experience has indicated that tilt is pretty insignifican't over all. At my latitude at least, Tilt unless flat or vertical is about 10%. Flat definitely works better in overcast conditions where I am and in summer too.
Atm I have Panels at 5o, 13o, 34o and 50o on my different arrays. The direction the panels face is a much bigger influence on generation where I am. While North is the ideal Direction for me, If I go ahead with another garage I'm thinking I would do an easy west roof to maximise the ramp up and down generation rather than add more to the already overly high peak. I have North and west panels now so having some east ( morning) facing would be ideal."
With PV so cheap and batteries still quite expensive, panel arrays just to grab AM and especially late afternoon sun do make sense. My neighbor wants to add a west facing set; they would like to cook their evening meal on electric. It's a pity that trackers are so expensive and maintenance prone. For our style of off grid living in our sunny location, minimizing battery use, a large tracked array would be marvelous. But it is cheaper to just add fixed or one axis adjustable arrays.
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The Kubota engines have much better quality control during the manufacturing process compared to the Chinese versions.
The gears driving the cam and counterbalance shafts are better machined and run at closer mesh tolerances.
Hence there tends to be much less backlash and clatter from the gear train.
Your RT125 should run a lot quieter than the Chinese counterparts.
Veggie
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Here also, a vertical west facing array for summer 3-7pm would be a plus for electric cooking.
Both my neighbor and I find that appealing.
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Odd starting problem. Valve lash, inj. spray pattern, injection timing all come to mind. My MB 300D is notorious for having cold start issues if valves aren't right on the mark.
Pity it's so hard to get some loaded run time on a bare engine.
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Hi Glort, sounds like you had a very productive trip. I`m not sure how the bump clearance is set on these engines but it does sound like it might be a bit too tight. A dribbling fuel injector might also have the same effect.
Can you let me know the details of the stub shaft you need, I might be able to turn one up on my mates lathe, next week.
Bob
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Noise at the intake is from early intake opening while still having exhaust pressure left. The overlap period where intake and exhaust valves are both open. You might try increasing intake lash to retard it somewhat though that may affect maximum power. There may be a range where noise can be reduced without much affect on power do to restricted intake opening. Worth a try, costs nothing.
My 1988 3 cylinder Kubota tractor engine has a hell of a clatter and bark, and not from the exhaust.
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Hi Glort, try your local Kubota dealer, they should have the original specs for hole spacing, three holes is a bugger (four is much easier to measure). There are ways of calculating the circumference based on the distance between hole centers but I`ve forgotten them, I`m sure they are available on the internet. Failing all else a piece of paper and a ball pein hammer will produce a very good template.
I don`t recommend trying to weld anything to a brake disk, depending what they are made of, you are unlikely to achieve a strong/lasting weld.
If the BIL is too flakey to do the job in a reasonable time my offer stands. Please be very careful about doing lathe work yourself, not that I doubt your talents or determination. I spent years working heavy industrial machinery and still have all my fingers and both eyes. Some of this was skill and some down to luck, I have had awkward shaped pieces fly out of lathes, fortunately they all missed me and my fellow workers. My advice to anyone using machine tools has always been: if you are not sure about it don`t do it!
Bob
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I think a brake disc may crack if you ask it to accept flex loads . . .
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In your earlier post you said that you had it running well on veg oil, perhaps you need a blend of veg with a touch of RUG at this time of year when it is cold.
I`m looking to buy a decent lathe and milling machine in the near future, maybe I can teach you what you missed out on with the FIL. I`m thinking Colchester for the lathe and either Bridgeport or Cincinnati for the mill. I`d love a surface grinder as well but the Wife will only stand for so much! :laugh:
You will always be welcome,
Bob
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PCD of three holes:
PCD = Pitch Centre Diameter so it's the diameter of a circle that you could draw that would pass through the centre of your three holes (excuse me if you already know this)
(1) clean the shaft with emery & measure the diameter with verniers - that's dimension one
(2) Use the stem of the vernier to measure from the shaft out to the inner edge of each hole. Average these three to minimise measuring inaccuracy - that's dimension two
(3) Do the same with the vernier to the outside edge of each hole and average as above - dimension three
(4) (dimension two + dimension three) divided by two, plus dimension one, is PCD - or as close as you'll get by measuring
FWIW it's effectively impossible to measure anything to the centre of a hole but usually OK to measure to each edge, add and then halve . . .
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Sorry, I have that wrong
one + two + three = PCD
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Good luck on the new welder. I just got an oxy-acetylene rig for myself. Tanks filled yesterday, just waiting on a B tank to regulator adapter. Got it for cutting and heating (bending), but looking forward to brazing and trying some gas welding too. Brazing and steel filler rods came to the PO today.
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Hi Glort, there is a way of seasoning timber very quickly. You need to soak it in a bath of ethylene glycol (anti freeze). This is an old trick wood turners used to use. The only problem with this is that you will never ever be able to get a varnish to adhere to wood treated in this fashion.
Bob
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Hi Glort, I've been running into a few cases of bad fuel recently and I was thinking that was the cause of your starting problem, but you've already investigated that, so like you I'm leaning towards the nozzle.
Sometimes after bleeding the fuel system thoroughly I like to turn the flywheel by hand very slowly and observe the injector spray pattern that way; it might tell something about the condition of the pump as well.
Good luck with it and keep us posted.
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I swear, Glort, you'd be rendering fat from Mortuaries or Kangaroos if you didn't have a supply of free used vegetable oil.
Seriously, your alt. fuel(s) and WI writing have been a boon for many of us.
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You're just caught in the better design issue. The better is always the enemy of the good enough.
My thinking now is that it takes about 3 builds to really get something close to right. You just have to take your lumps and not whine when you have to it again...
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Can anyone work out why I procrastinate and get myself in a tizz?
I'll give it some thought,
Cheers
Stef
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Can anyone work out why I procrastinate and get myself in a tizz?
I'll give it some thought,
Cheers
Stef
Take your time on that, Stef. Don't get worked up about it . . .
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Hi Glort, why do you procrastinate and get in a tizz? For exactly the same reasons that effect us all: distractions and self doubt.
You have both the machinery and the skills to bring this project to a satisfactory conclusion provided you follow a couple of simple rules. Firstly, you need to sit down with pen and paper and define the purpose of the project and what you are trying to achieve. Are you trying to build a backup generator, a full CHP system, something to take to shows? Perhaps it`s something to show off to the locals or just to piss them off. Maybe it`s just something to fill up your spare time and to stop you climbing the walls.
Second is to work out how much money you are able and willing to commit to the project. As a married man you will need to discus this with She who must be obeyed.(good luck)
Third is to decide where you are going to house your project, if it is going to be a backup generator it needs to be close enough to your home so that you can easily start it in the event of a blackout but far enough from you and the neighbors that it will not cause a noise/pollution problem, you also need to consider the cost of copper cable to your distribution board. If it is a CHP then it needs to be close enough to the house to allow easy/short pipe runs for heating. The closer it is to your home the more you will have to spend on sound deadening/vibration alleviation measures. If it is for display then it will need to have wheels so it can easily be moved, it will also require dry storage facilities between shows. If it is to impress/irritate the neighbors then it is all down to how well you know them and which of their buttons you want to push. I know that most of your proclivities are an attempt at finding positive ways of channeling past negative events into a brighter future, so the work is therapeutic and I completely understand that as I am in the same boat but it doesn`t have to result in a bad engineering outcome.
Fourth is design, once you have worked out what the goals are it`s time to get on the internet and have a look at what other people have done. Now cross reference everything you need with what is readily/cheaply available in your area, aim for the most bang for your buck!
Five is construction/assembly. Work methodically, don`t rush, allocate as much time as you can safely allow, without it effecting your other work or personal relationships, enjoy the process. Involve as many of your family and friends as you can, people always have more respect for a community project than an individual effort and they will all walk away a lot wiser from having been exposed to you and your knowledge and experience.
Six is taking credit for what you have achieved, light the fire pit, break out the wine and sit on your arse and accept the well earned praise for doing what very few people still know how to do!
Don`t ever doubt your abilities or knowledge, I don`t! :)
Bob
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Two things in the recreational drugs realm that where once being researched for medicinal use before the US "war on drugs" started are now being looked at again. Pot is profoundly helpful for depression in some that have had no luck at all with Rx medication. I can't tolerate enough THC for a big effect but do notice a nice boost in mood the day after if I'm vaping the 50/50 THC/CBD stuff in the evening to aid sleeping. Psilocibin/magic mushrooms seem to have very long lasting benefits for depression for some.
My WI injection system is still working nicely. I topped it up with 2 gallons of distilled water last week, have previously been using well water. I also replaced my plastic antifreeze expansion tank, they die from UV in about 4 years.
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Glort, (sp chk!) Saw your find. 1st one I've seen aside from mine. I might have a earlier version but still same basic design.
https://youtu.be/cExllSx6iqU
Do a search here for Kubota by me.
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Great custom portable design, XYZer. Nice looking welds, too.
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Maybe you could throw one of these on your new toy! https://www.youtube.com/watch?v=mhG6qqh2ooQ
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Loving that recoil starter, do they make them in different sizes for larger/smaller engines?
Bob
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Once again we find ourselves in the same boat, with too many options available. I am reasonably certain that I now have enough generating power to be completely off grid, while still being able to run my house and all the machinery in my shed. The one thing I am missing is battery storage.
I would love to be completely independent of the flakey/expensive electrical distribution system but my Wife is dead set against it. I am hoping that by installing sufficient home battery storage/solar/generating capacity that I will be able to export all of our present grid tied solar generated electricity to the grid to bring my electricity bill down to zero.
The biggest problem with my plan is the cost of deep cycle batteries. I have more than enough roof space to fit solar panels to charge them and more than enough generators to keep us going in the event of a battery storage problem. I would love to have a three phase and a single phase off grid inverter in place, giving me options on machine tooling and etc.
I am presently trying to design a floor slab and shed to accommodate all of this equipment, not an easy thing to do when you don`t know exactly what you are trying to achieve.
Bob
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Yes there are other starters of a similar nature, I can't remember much about it but I worked on a Deutz engine that was designed to be air portable, without any electrics, and drive an experimental pontoon / bridging set.
It looked like a starter motor and fitted in the same location, you wound it up in the same manner. but with a 1/2" drive ratchet, as I remember, and then let in go, I think it engaged with a bendix. The bosses son over wound one and it exploded like a hand grenade.
Bob, I've spent most of my life without knowing what I was trying to achieve, good, innit!
Cheers
Stef
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Glort's right about batteries, and for now, avoiding them. Sad that wet lead should still (100 years!) be the most cost effective battery for stationary power, but it is, and by a large margin.
A look at ongoing battery replacement cost should be a huge driver for super insulated off grid homes, but in my very rural area, it's not. People just can't grok it, and don't want to deal with the 3rd rate builders in the very rural SW. Instead they get a manufactured home and then find their AC eats batteries in no time, their PV and battery system is inadequate, and their propane bills in winter are huge. They go through the first set of batteries in 1 year, and that provides motivation. Then they switch to a evaporative cooler and other power conservation measures. Typically their battery bill is pretty painful, replacing 8 or 16 Trojan L16's (400ah) every 4 years, at $380 each plus tax and freight. Battery replacement cost of $100 to 150 month is common. They are energy independent but now battery dependent.
Building codes need to change, big time, and manufactured housing needs even bigger changes. My work with thermal modeling showed that a very well insulated slab, thicker than usual, was hugely helpful thermal mass for my SW high desert climate, when coupled with Canadian style double framed walls (R40) and raised heel trusses (R80). My next step is water cooling of the house though the in-floor pex system, which I keep stalling on.
My battery replacement cost is $15 a month, plus $15 a month for refrigerator propane for my larger sized propane refrigerator. By not having an electric refrigerator, and no 24/7 inverter losses, my DOD is only 10%, and cheap marine batteries do the job nicely. Heating is solar hot water and cooling I open windows at night. Works well except for periods of wildfires, when I can't open up, though I haven't gotten over 78F yet this year despite a lot of wildfires.
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I understand the cost, which is why the codes must change. In truth, the cost can be near neutral, as big savings in heating and cooling plants can be had. If your heating and cooling needs 1/6 the BTU's or less, it doesn't take much. And you can save on windows, as large expanses of glass are a thermal disaster.
Superinsulation via double wall is way cheaper than thick foam cladding.
No hope for affordable housing in Sydney, it's getting like San Franciso, property wise.
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Hi Guys, when I was building new houses in the UK it was almost impossible to keep up with the ever changing building regulations. It got to the point where I would demand the local council put in writing the regulations on the day I commenced construction, I would then build to that code. I had no end of run ins with building inspectors who turned up and told me that what I was doing was now against the law. I enjoyed handing them of a copy of the regs at the time of commencement of construction and telling them to Foxtrot Oscar.
I am appalled at the poor quality of Australian house construction, I suspect that Glort is right that the land values and government taxes have left the builders with no choice but to throw up the cheapest boxes they can, otherwise they would be unaffordable to any but the wealthiest Australians.
Perhaps Australian planners need to follow the UK example and specify that a certain percentage of new city houses be built to satisfy the demand from essential workers, policemen/nurses/sewage workers/taxi drivers and etc. Non of which could possibly afford to own their home otherwise. I would love to be involved in building/designing mews housing that would accommodate a lot of hard working poorly paid people at a price they could afford. Insulation against heat and cold would be the top priority.
The problem is that the government make a huge amount of money from taxation on energy for heating/cooling so they have no incentive to improve things. It`s a f*cked up world!
Bob
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I have thought for years that any new properties being built should be carbon neutral and be built with an expected life of at least one hundred years. I am not talking about the energy that goes into building a house, just the energy it consumes during it`s life time. There are numerous examples of houses around the world that actually export energy, while being perfectly comfortable for the occupants. If we can send people into space with temperatures approaching zero Kelvin is it too much to ask that our own homes are warm in winter, cool in summer and cheap to run?
In Australia this would be easiest achieved by building homes partially or wholly underground. this would produce a home with an ambient temperature of between 17 and 20 celcius, it would take no energy to cool these homes in summer and very little energy to keep them warm in winter. A few solar panels would be adequate to make these homes extremely comfortable.
Perhaps the easiest and cheapest ways to build these homes would be to build them on sloping ground, dig about half of the home into the ground and then use the spoil to bury the other half of the home. This approach would have one other benefit in that it would stop developers building on flood plains, leaving the fertile flood plains to farmers.
My local town, Grafton, is one such area in which the town center is built below the levies, in the event of severe flooding it will be several meters underwater, the insurance claims if it flooded would certainly be half a billion or more. We have seen exactly this played out in Townsville and Lismore in recent times. These towns/cities were built where they are because they needed river access to import/export goods. This is no longer the case, move the people out of harms way into the foot hills with a beautiful view of the productive and fertile flood plains below and let the farmers do what they do best.
Rant over for now,
Bob
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I looked into earth sheltered for my off grid home- not so cheap insulation, as it turns out, nor easy to build without having mold and ventilation issues. Here the stable earth temperature (63F) is down at 12 foot depth. I only have 4-5 foot of dirt on top of sandstone. Just adding insulation, and having the slab fully insulated as valuable thermal mass was the best bang for the buck, for my climate/location. I bumped the slab thickness to 5.5 inches and used 5/8 sheetrock to boost interior mass on the cheap.
Every region has it's own resources (such as ground water) and earth temperature... pity we've made so little effort to use them wisely.
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Seasonal heat/cold storage would be sweet, the the amount to be stored is brutal. You need to make an ice house of sorts in the winter...to be used in summer, and a huge superinsulated tank of molten salts in summer for winter. Rather brutally expensive in each case.
The problem with home design is that we've left it to "the marketplace" with a few architects as hangers on. Architecture is an ART SCHOOL, so any technical knowledge is superficial at best, and the focus is on things like esthetics and lots of glass, which are a thermal disaster. (A greenhouse for growing food while providing a sunny space seems a lot more sane.) Marketing types rule, and people don't have the technical savy to sort it out. I remember a former neighbor raving about a (resistance) water heater he bought that was advertised as 99.9% efficient. I hated to tell him all electric water heaters were, as the elements are in the tank of water. He was pissed...and not happy with me for busting his delusional bubble.
In much of the US, there are no practical guides to higher efficiency houses..not even recommendations for your local county, etc. Just the minimum insulation requirements in the UBC.
The best education I found was to play "what if" with a computer thermal model to determine BTUs of heating or cooling needed. The hard part is getting good data on soil temperatures, a foot, 2 foot and 3 feet down for the winter scenario. Losses at the edge of an exposed concrete slab are huge, the more exposed with say fancy split face block, the worse the losses. A slab poured up to the uninsulated stem wall is the kiss of death, thermally, though fortunately in time it will usually creep away from the house and make a poor thermal break. Perimeter insulation is the hands down best bang for your buck, since there is so little surface area. There don't even sell affordable and easy to use products to put an insulating skirt at the stem wall...you have to make them, which explains where the builders are at.
Almost any field I've studied in detail appears to have be largely based on misconceptions clung to like a religious zealot, with precious little real science and data. Where humans are involved, it's a good idea to be skeptical about the prevailing wisdom and take a much closer look. That's hell for working stiffs, and they just don't have the time and must rely on local zealots.
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What about ground source heat pumps, I have never personally installed one of these but I have dug the trenches and laid the plastic underground pipes for them.
They work rather like a reverse cycle air conditioner in that they can provide both heating and cooling. In winter they draw heat from the ground, in summer they pump heat into the ground, using it a bit like a heat battery.
The heating/cooling is generally dissipated through underfloor pipes set into an insulated concrete floor, the idea being to maintain a constant room temperature of between 20 and 30 Celsius via an adjustable thermostat in each room. They are said to be extremely efficient and can be run off solar electric during the day, at night you can turn them off and rely on the heat/cool of the concrete mass of your floor.
Bob
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I've done quite a bit of reading on ground source heat pumps. Very efficient, and in many areas where cooling is as important as heating, a hands down winner. Even here, a superinsulated home could reduce the size of the ground source system (where all the bucks go) by 3/4 or more. They are quite expensive to build but in many climates the payback is there.
In my climate and terrain, with shallow sandstone, a series of well bore holes linked by shallow trench is the preferred method, as trenching to depth isn't practical.
If I was building over again here, I would seriously consider two wells, one near the house and a greenhouse. The water is about 65F as it comes out of the aquifer, about 150 ft down. That would directly (no heat pump) suffice for cooling my insulated slab floor and keeping the house at or below 76F, and be a good source of both cooling and heating for a greenhouse. The "waste" well would receive the waste water, so that a modest circ pump could be used (pipe into aquifer on both ends), instead of a lift pump. The source well could also provide the domestic potable water. Priming the circulation system is tricky as depth is greater than a surface pump; large commercial systems using this would just have a lift pump, which would have dramatically higher flow once the return well path was primed and "pulling". This method had been used in commercial greenhouses where geothermal heated water is available.
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It's crazy to use corrogated pipe buried in the earth for air you breathe. In time, it will become the same life threatening mold and bacteria disaster as all early solar hot air/rock storage homes. A fellow engineer at an AF research lab did it for his home in the low desert, and had to shut it down after a year...his wife and kids were getting sick. I think it's much safer and more energy efficient to run a ground source pex loop, in bores or deep trench, with the water to air heat exchanger. Much less energy to move the heat/cool.
If you must use pipe for air, it would need to be smooth, with carefully sloped with drains, and a way to clean it out.
You will also see a lot of greenhouses using corrogated pipe under the floor, as they think it will be a seasonal energy store. Baloney, look at the data for large installations and you will see it's a failure; the downward and outward conduction losses to the earth are so bad that I am not convinced that it is worthwhile. If foamboard is used along with massive excavation, then yes, you can use earth. An insulated water storage tank, however, can provide substantial storage, and I think at a much better price to build. A retired engineer build a small greenhouse with insulated water heat storage, collected data that showed impressive performance. He collected excess heat at the peak of the greenhouse during the day ajnd heated at night via small water to air heat exchanger.
I'm very interested in hydroponic greenhouse growing for my climate, but the real stinker is summer, as it really needs cooling via evap coolers besides reduced sun (shade/diffusers).
Hydroponics as bugs and diseases are brutal here, within 3 years you are in a state of constant warfare, as your garden soil is loaded with diseases and bugs. I quit growing outside after 3 years of being totally hailed out just before harvest. I was doing nothing but picking bugs, spraying oil and soap sprays, and copper soap sprays for pests and diseases. The first year you think you are a genius, then aphids destroy your late cold weather crops, powdery mildew and a variety of bugs get progressively worse each year. With hydro, you can sterilize the growing buckets/gutters/trays and/or media after each crop is harvested, so it's first year every year.
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same here BruceM,
I farmed a small plot for a few years until I realized the huge benefits of two other styles of growing...
1] Greenhouse hydroponics
2] Raised beds with framed plastic rain/hail covers.
Both are doing great. The trick with a greenhouse is to have thin lightweight reflective shade panels that can be placed over the sun-facing windows during the hot months. During summer my greenhouse is mostly shaded to the point where I use solar powered LED lighting on my microgreen crops. In spring and fall I remove the panels and get a lot of welcome solar heat. It still gets hot in summer but the auto-louvers and fans keep it manageable for plants.
An evaporative cooler at one end of the building would certainly offer great temperature control.
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For my own comfort and enjoyment of gardening, I'd like to try a passive evaporative cooling tower as I don't like the sound and magnetic fields of swamp coolers though the cool wet air is delightful. It's also appealing for reduced energy use since I'm off grid. But I concede that evap cooler(s)/walls with big fans are far simpler. I'm sticking to small projects for now, seeing how my health goes.
A friend who grows most of her own food is also using greatly restricted overhead light in her greenhouse in summer; only 20% of the ceiling space is glazed plus indirect light from the south glazing. Transpiration of plants plus lots of natural ventilation via screen doors keep her temps to 10F below ambient most of the time. She was very successful for about 7 years doing ebb and flow pea gravel hydroponics with Talapia in an IBC container until she could not find fish food without various additives which made her ill. She's growing in dirt in raised beds now. I'm convinced that hydro methods that allow replacement/sterilization of media and trays/gutters/buckets is best for keeping diseases and insects in check.
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I like your idea of solar panels to provide partial overhead shade for the garden, Glort. Some steel posts and thin wall rectangular steel tube (a good trial for your new MIG welder) between them as rails to hold panels would allow you to have as much or little shade as you want according to spacing between the panels. An interesting way to boost your PV and perhaps increase garden production.
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Heat capture for a water tank in a greenhouse is usually either radiator/fan from top of greenhouse, or pipes or fin tube pipe near peak, on thermostat to take excess heat.
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Even in colder winter climates, there is considerable excess greenhouse heat in the winter- all afternoon. You have to either throw it away via ventilation or capture it for night time use.