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| Knox at the Maine Maritime Museum in ... |
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andrew
| | Posted on Sunday, November 24, 2002 - 07:39 pm: | 
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Here are a couple shots of a 1-1/2HP 1904(?) Knox Marine Engine taken at the Maine Maritime Musuem in Bath Maine earlier this year (I am finally removing photos off the digital camera disk!). They have quite a large collection of marine engines, but most were not on display when I was there in the spring. Did anyone go to the fall Boat and Engine Show at the museum?
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andrew
| | Posted on Sunday, November 24, 2002 - 07:42 pm: |
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Here is a Kennebec at the same musuem.
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andrew
| | Posted on Sunday, November 24, 2002 - 07:50 pm: |
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Another nice original Knox in a boat...
It is amazing that any of the Maine built workboat engines survived the combined effects of salt water and bitter cold winters... not to mention the fog and the tide!
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andrew
| | Posted on Sunday, November 24, 2002 - 07:57 pm: |
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I guess I am on a roll here....
This Knox engine is at the Transportation Musuem in Owls Head, Maine. A wonderful musuem of early cars, motorcycles, and airplanes.... a few stationary and marine engines too...
This Knox is labeled as 1910.... but it looks earlier to me. Notice the base.
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act4
New member
Username: act4
Post Number: 1
Registered: 07-2009
| | Posted on Wednesday, July 08, 2009 - 11:14 pm: |
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Hello,
I'd like to know how these engines were started. Was there a battery powered ignition, or were they started by hand somehow?
Was the term "make and break" the name of a type of ignition system?
thanks for your help.
Act4 |
searcher
Senior Member
Username: searcher
Post Number: 313
Registered: 10-2004
| | Posted on Thursday, July 09, 2009 - 12:54 am: |
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I assume your questions are related to engines of this type and not specifically to the Knox engines you see here. However, the method of starting most engines of this type was generally the same. Rarely did these engines have electric starters until the late teens and then generally only in the bigger, heavier, multicylinder engines. The process of starting small engines like the ones shown here commenced with priming the cylinder with a small charge of gasolene introduced into the cylinder via a priming cup. The flywheel was then rocked back and forth a few times to get a better gasolene/air mix within the cylinder, i.e., create a more explosive mixture. These engines had various means of timing to control when a spark could take place. The flywheel was simply turned by hand (the brave used a crank but most simply grabbed the flywheel and gave it a spin)to produce the initial explosion and then the timing was set to maximize the power and efficiency of the succeeding explosions.
As to the actual ignition, some engines were make and break and some were jump spark. Make and break engines used dry cell batteries and a low tension coil to create the spark that ignited the gasolene/air mixture. The make and break method used a set of points inside the cylinder. Just before the explosion was to take place, the points made contact through a mechanical process. At the moment the explosion was needed, the points were rapidly separated, again, by a mechanical process. Upon sudden separation, the collapse of the electrical field caused a surge at the separation point. When everything was working correctly, the make and break process provided a fat hot spark that reliably exploded the gasolene/air mix.
Jump spark systems used the familiar spark plug that has seen little change over the past century. Again, there was a timing device of some sort and the cylinder was primed in the usual way and rocked. The jump spark engines used the same dry cell batteries as the make and break. However, in a jump spark system, the current was sent through a high tension vibrating coil first. The vibrating coil served as the method of creating the rapid collapse of the electrical field and hence produced a shower of sparks that jumped across the points of the spark plug.
The make and break system was electrically simple but mechanically complicated while the jump spark system was mechanically simple but electrically more complicated. The commercial fishermen going out in open boats preferred the low tension make and break system because, despite its need for constant adjustment, could survive taking a wave over the engine and not miss a beat. Water doesn't easily short out a low tension system whereas the high tension spark plug system would short out quickly if it got wet. While the Knox and Kennebec engines could be bought set up as jump spark, most were set up as make and break as they were aimed primarily at the commercial fisherman market. |
richardday
Senior Member
Username: richardday
Post Number: 772
Registered: 11-2003
| | Posted on Thursday, July 09, 2009 - 08:03 am: |
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Interesting photos. Andrew's point about the early KNOX with the so called "wine bottle" style base suggests closer to 1900 than 1910. The "wine bottle" style originated in the small steam engine era where it was simpler to move a small steam engine to a machine rather than the machine to an overhead line shaft for drive or for portable engines to drive sawmills, pumps etc. If one looks at a number of very early inboard boat engines you will see they didn't learn to mover the mountings to the center of the crankshaft until about 1900. This would permit lowering the engine nearer the bottom of the boat which would help with boat stability in foul weather conditions. Another related point it also lowered the mixer or carburetor for better fuel flow from the storage tank. |
searcher
Senior Member
Username: searcher
Post Number: 314
Registered: 10-2004
| | Posted on Thursday, July 09, 2009 - 10:45 am: |
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Earlier in this thread Andrew remarked that one of the Owls Head Transportation Museum Knox engines seems earlier than the 1910 label would indicate (the wineglass style as Dick Day put it). Andrew is quite correct. That basic engine most likely dates between 1902 and 1904. Knox engines after 1904, based on original catalogs, period magazines, and extant examples no longer exhibit the 'wineglass' form.
There are some confusing issues with dating the Knox (or most other engines for that matter). The cuts in Knox ads often continued unchanged for some time despite the fact the engines had undergone some redesign, undoubtedly a cost saving measure. The early wineglass design does occasionally show up in an ad after that design had been replaced for some time. Even some of the cuts in the Knox catalogs themselves were reused from earlier catalog versions despite the fact there had been design changes.
Another confounding issue with dating Knox engines is the fact that many parts had the hp cast into them. Engines of different hp were often designed to use common parts such as water pumps. For example, it is quite common to find a Knox engine with a 4 1/2 hp tag that has 7 1/2 hp cast into the water pump. One of the frustrating issues I have learned to deal with in dating Knox engines is the well intentioned restoration of the engines by someone assembling one 'complete' engine from parts of two or three engines. For dating purposes, one has to start with the basic casting and only then start looking at all the individual pieces attached to the casting. For instance, there were three changes in the water pump drive arrangements between 1904 and 1908 one of which required a very minor modification to the basic crankcase casting. It is a dead giveway to find that modification but with a variation of the pump drive that didn't require the use of that modification.
Sorry, I get long winded on the subject of Maine engines. At some point I will put all the Knox detail into a form that will include serial number ranges in relation to design changes and date ranges. It should be a help in dating and properly restoring these relics. } |
richardday
Senior Member
Username: richardday
Post Number: 774
Registered: 11-2003
| | Posted on Thursday, July 09, 2009 - 11:11 am: |
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Well said searcher but I grew up in New England and we knew the style as wine bottle vice wine glass. I guess history will not care what we call them. |
petedorr
New member
Username: petedorr
Post Number: 1
Registered: 04-2010
| | Posted on Tuesday, April 13, 2010 - 09:48 pm: |
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Trying to find out anything about who invented this engine |
Peter Grey
Visitor
| | Posted on Saturday, September 04, 2010 - 06:48 am: |
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I have an old newspaper cutting,which mentions that my grandfather, Walter Lawson Adams, a British engineer, was 'the designer of for the Knox engine, which was the first 12 (sic) type to develop 475 h.p. and passed all the allied government test'.
This undated (and somewhat incomplete) cutting was probably published post Great War, but also refers to my grandfather's visit to the US in the early part of this war - a trip not without its own highlights, involving being on a train to his embarkation port in the UK which was bombed and destroyed by German aircraft, and a short-lived voyage on the SS Arabic, which was torpedoed by German submarines. In the event, he survived both these incidents and went on to represent the British Government for a while, in the US, relating specifically to their contracts with the Curtis factory.
Hope that this sheds some light!
Peter Grey |
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