buenijo
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Just sharing something I did previously. Earlier this year I spent a few months designing and building a small air pump that mounted to the small engine cylinder head. It worked perfectly. The idea here was to use the crankcase piston to supply air to the furnace. The steam cylinder would mount to the cylinder head with the piston rod packing gland and air pump assembly between two plates with the lower plate sealing the crankcase cylinder head. The air pump assembly was made from ABS plastic sheets that I cut to shape and welded/adhered together with acetone (surprisingly effective). The assembly contained flexible plastic reed valves and it fit between the two plates over a hole in the lower plate that opened to the cylinder. I abandoned the idea in favor of a small dc blower fan because this offers far superior control for easily adjusting the air flow for changing engine output, shutting down, starting up, etc. Also, the air pump required a more powerful starting motor. A shame, because the air pump worked so well - and it was positive displacement so it would force air through just about anything I needed. I still find myself trying to find excuses to work it back into the project. BTW, the final air pump design could be pulled out from between the two cylinder head plates for service and slipped back in easily like a cartridge. A single hose on a barbed fitting was connected and air entered through a small filter on the other end opposite where the piston rod gland seal would be. Pop off the filter, then pull out the cartridge. Very cool. Uber simple design. But it's just too easy and low cost to buy a good blower fan for $30.

I put the oil pump in storage. I won't be dealing with that again until the alternator is ready for installation as the oil pump will mount on the alternator adapter plate - and this will not take place any time soon. Next step is to start making fire. I need to acquire the propane burner and start assembling a suitable combustion chamber. The goal is to establish a high temperature clean burn at a controlled rate of 10-15 KW. Once this is achieved, then a solenoid valve will be installed along with a spark plug for ignition (using the crankcase ignition system). Hopefully, the system will start easily at the desired burn rate with the flip of a switch. The solenoid valve will eventually be powered off a thermostat that senses steam line temperature (thermostat already sourced). If the temperature exceeds the setpoint, then the solenoid valve will close. After this point, I will form the steam generator coil and start building a test stand. I'll start assembling the steam expander only after I can safely and reliably generate steam at the required rate, temperature, and pressure. There is no timeline, but I hope to reach this point by the end of next year.

The oil pump works, but I arrived at a much better way to install it. I had removed the engine camshaft because I simply do not need it. However, I considered that I can use it to drive the oil pump directly. This will eliminate two sprockets, a chain, and the angle bracket - along with a need for a chain guard and chain lubrication. Eventually, an adapter plate will mount on the crankcase cover for mounting the alternator. I can then mount the oil pump on this adapter plate and couple the shaft to the M6 threaded rod extension on the camshaft (see pic). BTW, this is the oil pump that will mount to the alternator adapter plate. They are designed to install inside the crankcase of small scooter engines. I can buy these for about $5 each. This is a good illustration of my design philosophy. Repurpose readily available low cost parts with minimal fabrication, and minimize the parts count. For example, eliminating the chain drive was significant. I have the (general) design worked out. However, the devils are in the details. Things are working out well so far. If it all works out, then the final design can go into small production runs almost immediately with reasonable retail pricing and very low capital investment. But that's just the ideal, of course. Reality tends to be fussy about such things.

That's excellent. Still, I recommend contacting the company I linked as they know Porta boiler chemistry treatment (designed for traditional firetube locomotive boilers like yours). https://advanced-steam.org/5at/modern-steam/principles-of-modern-steam/portas-water-treatment/

If you all intend to put the locomotive back into service, then I think replacing the boiler is a good idea - and the practical alternative is a modern version. https://mackwell.co.nz/replacement-boilers/ You can likely retain the original boiler shell - just replace the internals including fire tubes and furnace.

I watched it. I like this guy. It's clear he knows steam. It's clear these amazing machines are capable of operating for hundreds of years if properly maintained. No planned obsolescence here folks.

Just sharing thoughts on the upcoming furnace install - just brainstorming really. I expect the furnace/steam generator/condenser test unit to be the single most time-consuming part of the project - partly for the inherent difficulty, and partly because I need to build an outside test stand. As mentioned previously, the furnace is based on a propane burner. I selected a low cost 50,000 btu unit available on Amazon. The burner will mount on the roll cage inside a duct flange on which the combustion chamber fits. Additional air admission ports will be provided in the base. For safety, the propane will be supplied with both a regulator and a normally closed solenoid valve. The solenoid is powered with a thermostat that senses steam line temperature. So, if the steam temperature gets too high, then the propane furnace shuts down. Ignition will be achieved using the crankcase ignition system. I already extended the length of the spark plug wire and tested it. Works fine. Once everything is set up properly, then the system will be started by opening the main propane valve and closing a switch. This will energize the starter/feed pump motor (which will fire the spark plug and pump water), and open the solenoid propane valve. Burner output will be more or less constant. Steam temperature will be adjusted by changing the feed pump motor speed. For testing, the high pressure superheated steam is to be directed into a stainless steel tubing coil contained in a water bath. A water circulation pump will continuously flow water from a nearby storage tank. This will condense the steam at full steam generator pressure. The cooled high pressure condensate leaves the coil through a needle valve which serves to set the system pressure as indicated by a water pressure gauge.

Free fuel. Chips. Mulch. Even logs. "ChipDrop matches people who want free wood chip mulch with arborists and tree companies who are trying to get rid of it. By signing up and placing a request you'll be added to a list of people in your neighborhood who are trying to get free wood chips. The next time a local tree trimming company is in your area, they might deliver a load to you."

Minor progress (I'll take what I can get). I found a low cost oil shaft seal for the oil pump shaft extension I installed. It seems to work well. Also, the damned barbed fittings I installed leak at the threads (chinese seem to have trouble with npt threads - among other things). I couldn't find crush washers of the right size, so I sealed the threads with jb weld. I'm quite certain this will work. The oil pump seems to have a higher flow rate than I expected. I may have to reduce the speed with a larger sprocket. Not a big deal. Looks like it's gonna work. I'll provide a pic after install. Gonna be a few weeks. (*)The oil pump is to be mounted differently. See post #28.

Modern wood chip fired steam tractor to be manufactured in New Zealand. https://mackwell.co.nz/mackwell-a35-engin https://mackwell.co.nz/wp-content/uploads/2023/09/Mackwell-A35-Brochure-compressed.pdf SOME SPECIFICATIONS:

I did get some parts for the oil pump install. But after tinkering a while, I decided to modify the design. This is an opportunity to explain part of my process here. The design philosophy centers on repurposing readily available low cost parts. It takes a lot of time to source the right parts - and ideas don't always work the first time. This is pretty much how all projects unfold. However, the difference here is I often come across near perfect components that are simply too expensive. I decline not (primarily) because I lack the means, but because the goal is to finally devise a system that can be produced cost-effectively at modest scale. Therefore, parts that are not easy to come by or otherwise costly do not pass muster. Other times, the parts are low cost, but the required modifications are too onerous (i.e. labor costs too high). It's frustrating, but it's the only way I see this working in the long run. While tinkering with the oil pump, I did a series of tests on the water feed pump. I operated the gearmotor at a fixed speed that fell within the engine design specs. I then made a series of five test runs each exactly 60 seconds and carefully measured the volume of water using a graduated cylinder. The volume came to precisely 165 ml on each test. The ability to maintain a constant water flow rate into the steam generator is important. Although, I designed a control system (simple and low cost) to compensate for variation. I also did a cursory test with a partial vacuum on the pump suction. This reduced and otherwise varied the flow rate (as expected). The implication is the condenser pressure must be maintained above a certain value - and this is not a problem because the system is designed as a CHP unit meaning a higher condenser temperature (and pressure) is inherent in the design. That noted, it's also possible to place a small booster pump.