Lister cs changover valve demo

[@joschmoyo4532]

Possibly the best low speed diesel engines ever made.

[@lewisgardner1660]

Is the low compression used for starting? Or does it have another reason?

[@NorfolkMancave]

Hello fella. The compression screw is really left fully screwed in all the time. You only need to lower it if your running a heavy load. Lister say run on low compression if engine is running 70% or more load.

[@able880]

That comment about running that engine to 70% load is correct - from listening to the engine run in this video he's probably only running at 4 to 500 RPMs- and looking at the pumps water flow he's probably only drawing about one horsepower off the engine- that engine at 4 to 500 RPMs that engine puts out about 3 to 4 horsepower- so at that speed you would leave the compression changeover valve closed at all times- that engine cannot be started by hand unless the compression changeover valve is closed- the compression is too low when the compression changeover valve is opened when it comes to starting - it has to be in the closed position to start the engine by hand- if you're running that engine at 650 RPMs it's a 6 horsepower engine- when you're running it as a 6 horsepower engine if your load runs from 0 to 3 horsepower as on a generator where you have varying loads you would leave the compression changeover valve closed as long as you're load is not going to exceed about a thousand Watts- if your load is going to be from 1000 to 2000 Watts on average then you would open up the compression changeover valve and decrease the compression ratio of the cylinder from about 18:1 over to 14:1 - with a generator when you switch to the lower compression that raises the KVA rating of the genrator it gives you far better voltage consistency or RMS simply means you don't get the surges when the AC Motors kick on and off as with refrigerators- also the engine Burns considerably less fuel when you're running on low compression vs. High compression- when those engines were designed in the 1930s diesel fuel costed 70 times more than it does today that's high sulfur diesel not road diesel either way compared to today it was extremely expansive - the high-compression was primarily for starting or moderate to low loads - they also made a 3 horsepower Lister so if you're load exceeded 50% you could open up the compression changeover valve on higher loads since the engine didn't have to create since a higher pressure in the cylinder that decreased your fuel consumption at the higher loads the engine was far more fuel efficient running at a lower compression it also saved a lot of wear on the engine running at lower compression

[@able880]

the Lister engines were ahead of their time when they were originally made those engines burned 1/3 less fuel then their counterparts because of the compression change over also that extended the service life between overhauls because of the reduced operating pressure- in that day if you wanted the same efficient service out of an engine as a Lister could provide you would have to buy a hot surface ignition engine generally those had a hole in the head that you would put a gasoline blowtorch in and and preheat the head 2 about 180 degrees Fahrenheit then when you hand crank the engine it would start- with the Lister as long as it was above 32 degrees Fahrenheit it could be started by hand on diesel fuel because of the higher compression then you could change the valve over to low compression and have the efficiency of a hot surface ignition engine- any engine today that uses a glow coil that's a diesel engine is actually a hot surface ignition engine they won't start on compression because there's not enough compression since they're only 14 to 1 generally speaking so the glow coil creates the external Heat to start it up - once a diesel engine is running it doesn't need that elevated cylinder pressure they're more efficient running at lower compressions like 14 to 1- they don't run very efficiently at the higher compressions because of the energy lost building that extra pressure in the cylinder

[@able880]

Normally you can't run that engine as slow as it is running in that video I looked at it a second time and I don't think he's running much over 250 to 300 RPMs if he had larger fly wheels on it he could run at 250 RPMs but with the flywheels that are on it the slowest you can run that engine is about 250 RPMs without its stalling- but regardless unless you know engines the average person can't get away with running that engine that slow it will build up carbon in the head because the upper cylinder temperature is not enough to burn all the fuel completely to where there's no carbon buildup in the head - as long as the engine is running the carbon will be soft but as soon as you stop the engine and the cylinder cools down the carbon will become hard as a rock and when you tried to spin it over to start it either the valves will be full of carbon and Leak Bad to where you're not building up compression to start or the cylinder will carbon lock and you won't be able to roll the engine over to start it it's hard to run a Lester below 450 RPMs without it building up carbon- the modern-day version of those engines are Arrow engines and Ajax engines they have been used in the oilfield since the forties and fifties- to run Jack pumps for oil wells and also generators to electrically charge pipe lines to reduce the electrolysis therefore increasing the life of the pipeline- when they're on generator service and use for generating AC power they generally are set up at 800 RPMs that gives you a ripple free RMS- it's the same with the Lester's it's the same engine as a 6 horsepower but it's set up at a fixed 17 to 1 compression they don't have a compression changeover valve in the head and they're rated at 8 horsepower at 800 RPMs those are primarily used for either higher horsepower or generator service they're still Made in India today They call them list listeroid engines they're made in China also all the parts are interchangeable with the older engines from the thirties

[@able880]

That's the longest production engine in history I think it's been being made for about 85 years now