What seemed a promising discussion for both this column and a future, dedicated article in the magazine came up on the ATIS internet mailing list recently. A young collector heard about a flywheel engine on a nearby property and asked for advice on retrieving it. The only problem was that the engine in question was believed to be down a well! As usual the list rose to the challenge, and list members were full of information about possible dangers, such as poisonous gases or lack of air, what organizations could help and safety precautions to take. It was a great disappointment to all of us, not least to the young man himself, when he discovered that a house had been built directly over the well!
Well, that ended that story, so as an alternative, we present the following thread of discussion, one that literally covers the world of engine collecting. It originated in Australia, where a collector has just completed the restoration of a 12 HP Root and Vandervoort, and, having run it successfully at one of his local shows, was confident enough to make some adjustments to its running. His victorious e-mail to the list prompted discussion about the preferences for engine running speeds in different countries, the stresses which can be placed on an engine and methods by which an engine can be slowed.
As ever, the following comments reflect a variety of opinions that surfaced during this discussion.
After talking with a fellow R & V collector in the U.S. the other night, I thought I might try his method of slowing the R & V down. So I went outside and simply took the main governor spring (the one between the weights) off the engine. Started up the 12 HP R & V and now it is running real slow at about 80-90 rpm. At this speed I have to get the fuel/air mixture just right, because if it missed a fire the engine will not get through the next compression stroke. You could go and make a cup of coffee between the mighty bangs now
You might find it may get more reliable once the rings seat in a bit.
What's the 'standard' in Oz for running engines at shows? Here in the States we tend to do what you've done, namely tinker with 'em to get 'em to run nice and slow. And usually it's just the engine running and not belted up to something 'working.' In England, the standard tends to be just the opposite; an engine running flat-out at full nameplate rated speed, often belted to a piece of equipment.
There're pros and cons to both approaches, and it really comes down to what pleases the owner. Personally, I like the look and sound of a hit-and-miss running nice and slow. What's most common is Oz?
The thinking exhibitors mostly go for a speed below the rated one for the engine when it was new. We realise that iron gets tired, too, and should not be stressed more than is required. Of course, there ARE those who think they should be run as fast and as noisily as possible to get them to go. These people are avoided by anyone with half a brain or more, as an explosion or similar IS imminent!
On the other hand, I'd bet more engines have been wrecked by the huge stresses of slow running than by doing a light day's work after loving restoration.
I would think the same thing. Running slow would create more stresses on the drive train and flywheels, etc. Kinda that inertia, momentum thing.
I fully agree that an engine running at almost stalling speed puts a horrible strain on the crankshaft. However, I did say that running BELOW the rated speed is, in general, a good thing. I did not advocate a speed so low as to cause needless stresses on the main components.
We are in total agreement then! It seems to me that running an engine at such low speeds that one has to resort to way retarded ignition and holes in the piston, etc., is a travesty. By the way, Petters produce spots regardless of speed!
What of the anomaly of the largish 2-stroke half-breeds and some of the hot-tube engines running in the sub-40 zone? You saw them at Portland -Barnett's Reid and that red Bessemer. They come up real sloooow and SQEEEEEZE - and barely poot over compression (just barely), and push off with just enough inertia to get over top a second time (repeat as necessary). Intuitively at least, that doesn't seem to put much strain on things.
Running a hit-and-miss 'till it almost dies is too slow, it does jar the wheels and keys. You can tell when it's too slow, though. They seem to be fighting the wheel.
Bill Cooper's 8 HP Famous H & M runs about 50, and unless you put your ear against the engine or feel the stack, you can't tell when it fires.
It seems there's no 'standard' running speed here in Australia, and I think the funniest thing at rallies is when you ask the owner a 'tech' question (like running slow) you get, 'I dunno, that's the way it was when I got it'!
In our great Aussie laid-back style, those words kinda say it real neat!
Now that I have proven that the R & V can run slow, the spring is going back on. I was happy with the speed the engine was running, but I had to satisfy my curiosity. I personally think the engine is under less stress at a moderate speed than at a very slow speed. The forces at work taking an engine from almost stopped to moving again are enormous, so I think a little quicker will be better. Another good reason is that at its usual speed, the governor looks really cool through the spinning spokes!
I don't think there is really a standard in running engines here in Oz. Most of the engines running something seem to be running below the rated speed, as most are running something that is well below the HP of the engine.
I think the 'she'll be right mate' attitude extends to engines, and people just do what they feel like. You don't tend to see engines running dead slow like in the U.S., or engines running at their rated speed. I think we have chosen the middle ground.
Many of the engines at shows here are hot-bulb engines (Australs, Black stones, etc), which you can run very slow, except for one little problem: If you run them too slow they cool off, and if they cool off too much, they stop.
I'd agree that if the engine is not belted to any load, then seeing it run nice and slow is what most of us in the States prefer. What I like is seeing a slow running engine that barely makes any noise. Last weekend at the Bottimore swap meet there was a 15 HP Ingeco side shaft engine for sale. The owner was running it off a propane tank. He started it by priming it with gas, and after the first few bangs on gas he'd switch it over to propane. On propane it just ran nice and slow, and hardly made a sound. I love watching engines like that run. Unfortunately, at $12,000 it was out of my price range.
I've seen a fair number of vertical F-M T engines with the electric flywheels at shows, and more often than not they are running slow and have no load. However, if you see one hooked up to a generator like it was intended, it is something else.
I have no personal experience being around these old engines when they were being used as work engines, but I'd guess that for people that were around them, the working sound and speed is what they remember and for them, that's what they'd like to see.
I think a good show needs a mixture of both. The slow-running engines are enjoyed by the general public because slow running makes it is easier to see what is happening. The slow-running engines are also enjoyed by the collector that understands some of the challenges of getting a engine to run real slow and quiet, as well as being able to better see the mechanical workings of a particular engine.
The working speed engines are also needed so the general public knows what the engines were really used for. Otherwise, they may think it was just an old-time entertainment device that people stood around looking at! Then of course there are collectors that just prefer the sound of an engine working.
I think that running slow with the original timing for running fast (advanced) would give the sharp report and thus the stresses you mention, but most engine operators set the timing WAY retarded so that the firing is more like a fart half way down the power stroke (no stresses there).
Take care of your old iron and make the most of what's left of the restoration season - we're already well on the way to the 2002 show season!
Engine enthusiast Helen French lives in Leicester, England. Contact her via e-mail at: Helen@insulate.co.uk. Join the ATIS mailing list at: http://www.atis.net.
'There're pros and cons to both approaches, and it really comes down to what pleases the owner.'
'I personally think the engine is under less stress at a moderate speed than at a very slow speed.'