Found: URGENTLY - Fan Pulley Ford Lynx 12V Generator

[motto (RIP)]

Sounds like the bearings may have been 6203 Rick. These were/are used in a lot of generators and alternators and so are worth keeping a few around the place. I carried one as a spare after having a generator lock up on my Chev years ago. They even fit the cutting deck on my ride on mower.
A fellow was selling them for $2 each at the Bendigo Swap a couple of years back and I bought a number of them.

Dave

[lynx42]

Originally Posted by motto

Sounds like the bearings may have been 6203 Rick. These were/are used in a lot of generators and alternators and so are worth keeping a few around the place. I carried one as a spare after having a generator lock up on my Chev years ago. They even fit the cutting deck on my ride on mower.
A fellow was selling them for $2 each at the Bendigo Swap a couple of years back and I bought a number of them.

Dave

Yes, David, 6203 is the sealed bearing which I chose to put in. Won't have to oil the genny now.

Regards Rick.

[Lynn Eades]

Tony, Rick etc. Not sure about Ford, but here's a little on Lucas.
A Lucas 6 volt generator will produce 12 volts. It will in fact produce 50 volts, (unregulated) but not for long.
a 6 volt genny can be converted to 12 volt by changing the field coils in from a 12 volt genny. This however does not work in reverse as the 12 volt armature cannot handle the current. The wiring needs to be heavier for the 6 volt.
This works because Lucas have built 6 and 12 volt generators using the same basic design. In particular I have been able to build a 12 volt genny for my carrier using the end plates and armature that came from a model of generator that was only ever built as 6 volt (original carrier)

On the Ford pulley numbers. Those numbers are probably just casting numbers.
A Ford part number is usually made up of three parts:
Here is a basic run down.
The root number (eg 10130) refers to a generator pulley.
The prefix (eg 01AS) which denotes country and year of origin and particular vehicle application. (I have no reference material to decode the 01AS. This may mean the part is specific to the Lynx armoured car)
The last part is the suffix (in this case a "D")
The "D" denotes changes or improvements in that item and so you might have a pulley that to all intents is the same. however they may have added material to strengthen the design, improve the air flow from the fan, or maybe even dynamically balanced as opposed to a static balanced original (just trying to come up with examples) Each time a design improvement is introduced, the suffix changes.
Someone like Tony Smith will be able to explain this in more detail.

I think Henry came up with a great system. If you have a war time Jeep or a CMP or a 1972 Ford Escort, the root number for an engine block is 6xxx It is the prefix and suffix that change.

[Tony Smith]

Originally Posted by Lynn Eades

A Ford part number is usually made up of three parts:
Here is a basic run down.
The root number (eg 10130) refers to a generator pulley.
The prefix (eg 01AS) which denotes country and year of origin and particular vehicle application. (I have no reference material to decode the 01AS. This may mean the part is specific to the Lynx armoured car)
The last part is the suffix (in this case a "D")
The "D" denotes changes or improvements in that item and so you might have a pulley that to all intents is the same. however they may have added material to strengthen the design, improve the air flow from the fan, or maybe even dynamically balanced as opposed to a static balanced original (just trying to come up with examples) Each time a design improvement is introduced, the suffix changes.
Someone like Tony Smith will be able to explain this in more detail.

01A is the model code for a 1940 model standard Ford car. the "S" denotes a special part. To my eye, it may relate to the belt width, which looks in the pics to be wider than the regular "Wide belt". The Suffixes A, B, C, etc usually denote variable or interchangeable parts, in this case would be for pulley diameter.

Originally Posted by Tony Wheeler

"This led me to consult the parts list, whereupon I discovered there were in fact two different diameter pulleys fitted, nominally 3 1/2" and 4 1/2", the explanation for the smaller one being: "Use where low cut in speed is desired."

What this means is that the refers to the engine rpm when the Regulator Coil will close and provide charging current to the battery. A smaller pulley relative to the Crank pulley will turn the Genny shaft at higher rpm. The voltage output of the Genny will exceed Batt Voltage at a lower engine speed than with a larger Genny pulley. Generally, the larger pulleys were fitted to cars where engine speed would be quickly increased when driving, and usually sit at a higher cruise rpm. Light commercials and heavy trucks would be specified with progressively smaller pulleys, as these vehicles spend more of their duty cycle in lower rpm ranges.

In Ford Military Vehicles, the smaller pulleys were specified for vehicles that would spend time idling so that the Genny would spin fast enough to charge the Battery at high idle speeds. Typically Radio equipped vehicles, or those that made use of the PTO for a specific function.

I do have a list of the various sized pulley part numbers in both Single and Twin belt varieties.

[Tony Wheeler]

Originally Posted by Tony Smith

01A is the model code for a 1940 model standard Ford car. the "S" denotes a special part.

Very interesting Tony, and if you go back to Rick's original post where he gave his Lynx pulley dimensions you'll notice the front flange diameter is 2 3/4", whereas the pulley in my photo is 81 mm, which is closer to 3 1/4". Perhaps that's what the "S" relates to in the Lynx part number. Precisely what effect it has I don't know - I have other 4" pulleys (ie. 4" rear flange dia) with different front flange diameters again, but they all appear to fit the same belt width. Of course that's to the naked eye - you'd have to actually fit the belt and measure exactly how far out it sits to be sure. Perhaps there were slight variations to adjust rpm for particular applications, eg. the Lynx on 12V may have run a slightly smaller pulley diameter (ie. effective pulley diameter) to operate at slightly higher rpm. All speculation of course but the "S" would presumably indicate some kind of functional difference.

I'd like to see a photo of Rick's old pulley, and whether it has a part number on it. Of course there's no guarantee it's the original Lynx generator but it's quite likely to be.

[Tony Smith]

Originally Posted by Tony Wheeler

Perhaps there were slight variations to adjust rpm for particular applications, eg. the Lynx on 12V may have run a slightly smaller pulley diameter (ie. effective pulley diameter) to operate at slightly higher rpm.

A smaller pulley will spin faster, meaning it will put out a charging voltage at lower rpm. If you plan on routinely running at higher rpm, a larger pulley will be a better choice.

[Lynn Eades]

Tony W. the difference in the field windings has to be the number of windings, and therefore the strength of the magnetic field. How this converts to voltage I am not sure (I remember less than I've forgotten) but my guess is that the stronger the magnetic field the higher the voltage at any given armature speed.
The problem unregulated, is the overheating and melt down. (melting and throwing of the commutator solder? etc.)
With the part number prefix, the C01W the C= Canada production, and the "0" is 1940. The other bits I cant help with.
Ford built a Carrier engine that was a "79E 6004 C.S. I think the 79 refers to a basic engine build. (I dont know)
On that note:
There is a Chilwell publication No. 79/49 titled "Engine Build Up Data" Anyone have a copy?

[Tony Wheeler]

Originally Posted by Lynn Eades

Tony W. the difference in the field windings has to be the number of windings, and therefore the strength of the magnetic field. How this converts to voltage I am not sure (I remember less than I've forgotten) but my guess is that the stronger the magnetic field the higher the voltage at any given armature speed.
The problem unregulated, is the overheating and melt down. (melting and throwing of the commutator solder? etc.)

Yes but you're forgetting current Lynn, since magnetic field strength = current x number of windings. What I'm thinking is the 12V field coils have more windings, and therefore more resistance, so they draw less current. The net result is the same, ie. same magnetic field strength, because the lower current cancels out the extra windings. Conversely, if you put 12V through a 6V field coil, let's say a Ford 6V field coil rated at 3 ohms, it will draw twice the current it was designed to carry, and potentially overheat like you say. Evidently they can handle it, because some of the rodders leave the 6V field coils in and report no problems, but you wouldn't put 12V through a 6V globe and expect it to last as long, so why expect it from a 6V field coil? Correct practice in theory would be to match the field coil to the voltage it will operate at, so I'm thinking the use of 12V field coils is IDEAL practice, although not necessarily ESSENTIAL practice. For example I notice the professionally converted 6V gennys all have 12V field coils fitted, possibly because they have to give a warranty...?

The same doesn't apply to the armature, because the situation is reversed. That is, the 6V armature is designed to carry more current than the 12V armature, because you need twice the current at 6V to produce the same wattage. Which means the 6V Ford armature running a 12V system is operating well BELOW its designed current load. Which would explain why no one changes them, including the professional genny converters.

On the question of magnetic field strength - like you I'm a little hazy on some of the complexities of generators, but I know they operate fundamentally under Faraday's Law, which dictates that voltage output is proportional to the number of armature windings x the speed they move through the magnetic field. In other words - RPM. Which means voltage has nothing to do with magnetic field strength, that just determines the potential current output at a given RPM. And of course if you draw more current you need more power to drive it, eg. when you turn on the headlights at idle you can hear the motor being loaded up. So what I'm wondering is if you run 6V field coils on 12V, which doubles the current through them, and therefore doubles the field strength, does it double the potential current output? And is that a good thing or a bad thing? Maybe it's a reason to change the field coils....?

Anyway I'm thinking a lot of this genny theory has more to do with current than voltage, which is simply the job of the regulator. Like you said earlier the 6V Lucas genny will put out 50V if you let it, so they're really not a voltage critical device - it's only the field coils which are voltage rated, because they're fixed resistance.

My brain is hurting now so I might get back to something mechanical!

[Richard Farrant]

Originally Posted by Lynn Eades

Ford built a Carrier engine that was a "79E 6004 C.S. I think the 79 refers to a basic engine build. (I dont know)
On that note:
There is a Chilwell publication No. 79/49 titled "Engine Build Up Data" Anyone have a copy?

Lynn,
There were two variations of engines for the Carrier No.1 Universal (inc. other types).
Type - DS No.1 engine assy. no. 79E-6004-DS which had Lucas starter, dynamo, coil and distributor (assume this to be an English engine)
then there was;
Type - CS No.1 engine assy no. 79-6004-C this had a slight difference in external parts, inc. fitment of a Ford distributor and dynamo

ref. to Chilwell no 81/49 Engine Build-Up Data Book

[Tony Wheeler]

Originally Posted by Lynn Eades

The prefix (eg 01AS) which denotes country and year of origin and particular vehicle application.

Thanks Lynn, that might explain why some of my pulley part numbers don't appear in the parts list. For example 79-10130-C on one of my 4 1/2" twin belt CMP pulleys. The parts list only shows prefix 01W and C01W.

Good info on the Lucas genny too, I imagine much the same would hold true for the Ford genny as well. It's the same physics involved, all governed by Faraday's Law. The faster you spin a genny the more voltage it will generate, the only question being whether it's in a useful rpm range for the vehicle. The way my F15A revs on the highway with 16" wheels I suspect it could run a 24 volt system!

Changing the field coils interests me - from my limited knowledge it would only vary the current, not the voltage. I'm not quite sure why it's done, hopefully someone will educate me!