New 39T/13T Ruckstell Crownwheel and Pinion

[John E. Guitar]

I'm rebuilding the Ruckstell on my 1924 Tudor at the moment.

I have a new 39T/13T crownwheel and pinion that I picked up a few years ago off a guy who was getting out of the hobby.

The crownwheel has a copper colour to it. Has anyone come across this before? The item is magnetic.

Both items are stamped with FM in a circle, which I think is the manufacturers mark.

I heard there was a bad batch of these that came out of Argentina but I assume they would have been stamped Industria Argentina (Made in Argentina).

[Dan McEachern]

That's not a Ruckstell ring and pinion- those were a 13 tooth pinion running against a 40 tooth ring gear. What you have is a 3:1 ring and pinion manufactured for and sold by Mark Auto. Most T parts dealers had these available in their calalogs, but they came from Mark Auto. The FM/circle mark indicates they were actualy made by Fairfield Manufacturing in Indiana. Fairfield is a well known manufacturer of bevel gear sets and have been in business for many years and was recently acquired by Dana Corporation.

The copper plating on your gear set is part of the heat treating process that prevents case hardening of the gear body while allowing the teeth to be carburized and hardened and tempered.

[John E. Guitar]

Dan, thank you, that is a relief. I'll use these in the car.

I know Fairfield for their Torque Hubs. It's interesting that they made aftermarket Model T parts.

[Allan]

John, a 3:1 ratio rear axle can be a drawback with a heavier car, even with a Ruckstel, unless the engine has had a few tweaks. I feel a 12 tooth pinoin on that ring gear, to give a 3.25:1 is more manageable. It works well in my D and F roadster.

Allan from down under.

[John E. Guitar]

Allan, it’s got a hopped up motor so it should be fine.

[Aussie16]

I hope it is "Hopped up" pretty good John. The 3:1 not in a Ruxstell with a heavy body, you will want to have plenty of Pep to keep it pulling.

[Les Schubert]

I totally agree with Landy and others. 3-1 gears in a heavy car like a tudor is going to need some SERIOUS extra power to be nice to drive. Last year a local guy drove his coupe with 3-1 on a hilly tour and spent just about the entire tour in low Ruckstell. The Ruckstell is now about worn out and I view the car as unsafe. If you have good auxiliary brakes then at least you shouldn’t kill anyone!!

[Scott_Conger]

In a Tudor, especially or even with a 'hopped up' motor, you will either be ALWAYS starting in Ruckstel or slipping/abusing your low drum. That would be way too much shifting for me, personally. I drove a friend's touring in FL (flat) on a tour and it was not easy to get it hooked up in low and he admonished me that he ONLY wanted the car started in Ruckstel, and that was with only two passengers. After complying, I decided he was right and that was the only way to repeatably and safely get the car rolling...again, too much shifting for me.

[Kenny Edmondson]

+1 on not using 3:1. Gonna be unhappy with yourself.

[Les Schubert]

I just bought a 12-40 (3.33-1) gear set. If you live near sea level and flat country and have some power you might be interested in the idea

[Scott_Conger]

Les' suggestion is a good one...that is a good Ruckstel combo.

[tselliott]

I have some Ford pinion gears that have that same copper sheen on them after coming out of the bead blaster.

[John Page]

John,
I was a member of the MTFCA when I got our Fordor in 1978. There was no Forum at that time. I remember articles in the Vintage Ford advising against using the 3 -- 1 Crownwheel and Pinion on the heavier Sedan cars. I used the standard ratio and have had good service with that set-up. ( Restored in 1989 so 32 years this year. )

Your car would be about the same weight as ours.
Maybe a little heavier as our car has some aluminium panels. ( back upper quarter and the door skins)

If your car has the all steel doors that would also make it heavier.

Best regards, John Page, Australia.

[John E. Guitar]

Thanks for the advice guys.

I'll go with the 40T/12T combination on the Tudor and set aside the 39/13T gear set for another car.