Free wheeling

R

Ruth

Well-known member
I was perusing "Those Wonderful Unauthorized Accessories" book and came across a bunch of devices for Free-Wheeling.

What exactly is free wheeling, why would you want this and does anyone actually have one on their car now?

Seemed to be popular back in the day.
 
I used to free wheel downhill by simply slipping my A into neutral and taking my foot off the clutch. I once reached nearly 60 mph on Hwy 1 out of Stinson Beach, CA. Scared the bejeezus out of me. Then I grew up.
 
If you have a Borg Warner O/D it has a free wheeling state. With the lockout cable "in" and the solenoid un powered, your A will free wheel when you let up on the gas.
 
Free wheeling is when the transmission is disconnected from the rest of the drive train either by slipping the gearshift into neutral or through clutches that allow power to the drivetrain but slip or disconnect when coasting. Coasting in neutral is another way to think of the same thing.
 
Ruth said:
I was perusing "Those Wonderful Unauthorized Accessories" book and came across a bunch of devices for Free-Wheeling.

What exactly is free wheeling, why would you want this and does anyone actually have one on their car now?

Seemed to be popular back in the day.
Click to expand...
Think of how your bicycle operates - when you pedal (aka "apply engine power") it's connected to the rear wheel and drives you forward, while when you coast it allows the rear wheel to, well, free-wheel. Back when I learned to drive this was the way to conserve gasoline going downhill and minimize the amount of fuel you had to put back into your parents' car so that they didn't know you'd been driving all over hell-and-back instead of going to the library like you told them.

JayJay
 
If the terrain where you drive is hilly, on a downhill you might prefer to put the car in neutral and let gravity propel you. But without synchromesh, getting the car back into gear when the hill runs out could be risky. A freewheel clutch is interposed between the transmission and the rear end. It solves this problem by using ratchets or springs or another mechanism to automatically detach the transmission from the rear end whenever the rear end shaft starts to turn faster than the transmission shaft – effectively putting the car in neutral without the driver needing to engage the shifter. When the car slows down or the driver accelerates, the transmission shaft rotational speed catches up to the rear end shaft rotational speed and the freewheel clutch automatically reconnects the two at the moment they match.

So the appeal is that you don't have to get back into gear when you're finished coasting, the freewheel does it for you. You just let off the gas to disengage and hit the gas to re-engage.
 
OK, I can free-wheel by slipping the trans in neutral. But why all of these aftermarket devices for free-wheeling? Even Ruckstell and Cragar had ads for them?
 
With a stock model A transmission I would be careful about putting it in neutral in real hilly country, unless you are familiar with it. Once the car reaches pretty high speed it could be difficult to get back in gear and restore some engine breaking.
 
Ruth said:
OK, I can free-wheel by slipping the trans in neutral. But why all of these aftermarket devices for free-wheeling? Even Ruckstell and Cragar had ads for them?
Click to expand...

Maybe?

"By its nature, a freewheel mechanism acts as an automatic clutch, making it possible to change gears in a manual gearbox, either up- or downshifting, without depressing the clutch pedal, limiting the use of the manual clutch to starting from standstill or stopping. The Saab freewheel can be engaged or disengaged by the driver by respectively pushing or pulling a lever. This locks or unlocks the main shaft with the freewheel hub."
https://en.wikipedia.org/wiki/Freewheel
 
Many early to mid 30's cars were available with free-wheeling either as standard or as an option. It soon fell out of favor as it was dangerous because of the lack of engine braking and sometimes mediocre brakes. I had a 32 Essex Super Six that came with free-wheeling and it could get pretty scary on a long/steep hill. I hardly ever used it and I was in my teens and therefor "invincible". An old mechanic that I knew at the time told me that "up to 50 mph you are driving the car, over that speed, you are aiming it"
 
TerryH said:
With a stock model A transmission I would be careful about putting it in neutral in real hilly country, unless you are familiar with it. Once the car reaches pretty high speed it could be difficult to get back in gear and restore some engine braking.
Click to expand...

That's the freewheel problem right there. Easy to get out of gear – hard to get back in it. Aftermarket freewheel clutches often advertised ways to manually re-engage the drive shafts if needed, but I imagine there were accidents where people panicked and couldn't manage to hit the button.
 
The most efficient method is incorporated in the borg warner r10 OD,it freewheels through a planetary gear set..the drive shaft is fully supported resulting in an almost friction free operation.

Spinning your main shaft faster than your engine can turn your main drive gear is the risk with "hillbilly overdrive" or kicking it into neutral,over run or 'pucker factor' a spur gear transmission and there is no means to match the gear speeds or synchronize it.

Biggest issue is engine compression isn't used when braking.. had a friend with a '53 customline and OD..we'd get that thing up to 90-95 mph,ore than once he damn near dished the steering wheel pulling back while he stood on the brakes in a panic stop.... imagine the fun with mechanicals
 
updraught said:
Maybe?

"By its nature, a freewheel mechanism acts as an automatic clutch, making it possible to change gears in a manual gearbox, either up- or downshifting, without depressing the clutch pedal, limiting the use of the manual clutch to starting from standstill or stopping. The Saab freewheel can be engaged or disengaged by the driver by respectively pushing or pulling a lever. This locks or unlocks the main shaft with the freewheel hub."
https://en.wikipedia.org/wiki/Freewheel
Click to expand...

Thank you. That makes perfect sense to me. One unit I see in the ads actually replaces the drive shaft so I can see now that you could disengage the transmission from the rear end.

Now that I am thinking about it, that is one of the features of a Mitchell O/D. You can put the Mitchell in neutral and shift the stock trans.

Great info, thanks. pretty interesting accessories they had back then. Fun book to read. "Those Wonderful Unauthorized Accessories for the Model A Ford".
 
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Lots of good reasons to not put your Model A or any car for that matter in Neutral and free wheel. A good one for me is NOT having the engine assist to slow you down. As mentioned above we want to drive our cars not "aim" them. Not to mention difficult if not impossible to get the A into 3rd gear. 40 mph max speed for me...thank you very much. Enjoy the ride!
 
JayJay said:
Think of how your bicycle operates - when you pedal (aka "apply engine power") it's connected to the rear wheel and drives you forward, while when you coast it allows the rear wheel to, well, free-wheel. Back when I learned to drive this was the way to conserve gasoline going downhill and minimize the amount of fuel you had to put back into your parents' car so that they didn't know you'd been driving all over hell-and-back instead of going to the library like you told them.

JayJay
Click to expand...
Back when I was in collage in the late 70's, I would coast down some of the hills coming home to save gas, but only on the back road I took. Almost no traffic and the hills were not really steep so the car I was driving never got any real speed. 1967 VW bug. :)
 
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