Posted By |
Discussion Topic:
1939 Mercury drive & pinion shaft
|
|
admiral1960 |
09-16-2012 @ 5:11 PM
|
|
|
Member
Posts: 63
Joined: Oct 2009
|
Hi, My brother has a 1939 Four Door Sedan. He will be installing a Columbia rear end this winter. He was telling me that the drive shaft is welded to the pinion shaft. As I have not heard of this before I was wondering if this is common in Mercs or a one time thing with his car. Can anyone fill me in on this ?? Thanks !!
Allen E Michler AW1, USNR (10 yrs) LTC, TC, USAR (29 yrs)
|
ford38v8 |
09-16-2012 @ 6:55 PM
|
|
|
Senior
Posts: 2739
Joined: Oct 2009
|
Allen, I don't know much about Columbias, but one thing I can tell you for sure is that the driveshaft is definitely not welded to the pinion shaft. Alan PS~ Not the first time I've had egg on my face! See my later post...
This message was edited by ford38v8 on 9-16-12 @ 9:18 PM
|
supereal |
09-16-2012 @ 7:36 PM
|
|
|
Senior
Posts: 6819
Joined: Oct 2009
|
An exception would be if a coupler/adapter was used to mate different splines. We weld them to driveshafts, but never to a pinion, but it could be done. If whomever did it, they may not have used a coupler, opting to make it a one piece connection. I've seen stranger things.
|
ford38v8 |
09-16-2012 @ 9:16 PM
|
|
|
Senior
Posts: 2739
Joined: Oct 2009
|
I misunderstood the question, thinking I was reading "axle" rather than "driveshaft". The Mercury driveshaft was integral with the pinion. I hadn't known that fact myself until maybe a month ago.
Alan
|
admiral1960 |
09-16-2012 @ 10:30 PM
|
|
|
Member
Posts: 63
Joined: Oct 2009
|
Alan, So you are saying that the drive shaft and pinion are one piece (welded together ?). I would have thought that it was due to not being able to use a coupler for some reason. I am curious as to how the rear end gears get changed like when I changed my 35 Ford from 4.44 to 3.54. Perhaps someone can educate us.
Allen E Michler AW1, USNR (10 yrs) LTC, TC, USAR (29 yrs)
|
admiral1960 |
09-16-2012 @ 10:33 PM
|
|
|
Member
Posts: 63
Joined: Oct 2009
|
Can anyone tell me where I might find an explanation, illustrated parst breakdown or something that will definatively explain or show how the 39 Merc rearend is constucted ?
Allen E Michler AW1, USNR (10 yrs) LTC, TC, USAR (29 yrs)
|
ford38v8 |
09-17-2012 @ 12:27 AM
|
|
|
Senior
Posts: 2739
Joined: Oct 2009
|
Allen, I haven't seen the setup, but would think the Merc would be the same as the Ford with the exception of the one piece drive/pinion. I don't have any idea why they did that, but it means that the driveshaft goes along with the banjo in any upgrade to a Columbia, which in turn means the torque tube as well, to prevent bending the driveshaft in handling.
Alan
|
supereal |
09-17-2012 @ 10:09 AM
|
|
|
Senior
Posts: 6819
Joined: Oct 2009
|
The fact that the driveshaft and the pinion are joined shouldn't make much difference when installing a Columbia, as the pinion isn't removed from the banjo, anyway. I am attaching a page from the Canadian shop manual which outlines Columbia installation. The C&G catalog shows an installation manual for the Columbia. The '39 book is item # 39-COI, and is not expensive. I don't know the current price, but my old catalog says $4.
|
admiral1960 |
09-17-2012 @ 5:10 PM
|
|
|
Member
Posts: 63
Joined: Oct 2009
|
My brother said he was going to install the columbia by replacing only the half (right side?) with the Columbia mechanism. I assume that means leaving the original drive shaft/pinion gear installed. I thought it required a different ring & pinion gear set but appparently not. He is running 3:54 rear end and I would personaaly switch to 3:58 to make the Columbia more usable on hills.
Allen E Michler AW1, USNR (10 yrs) LTC, TC, USAR (29 yrs)
|
TomO |
09-23-2012 @ 4:50 PM
|
|
|
Senior
Posts: 7244
Joined: Oct 2009
|
The stock rear end ration on the 39 & 40 Mercs is 3.54:1. The pinion gear is part of the drive shaft and to change ratios, you must replace the drive shaft. A Columbia added to a 3.54:1 ratio differential may not deliver very much if any high speed improvement or an increase in gas mileage, due to the extra loading on the engine. I am pretty sure that most factory delivered Columbia in the Mercury, were installed with the 4.11:1 ratio drive shaft and ring gear. The 1940 Chassis part manual specifies the "shaft-drive & pinion &driving gear matched pair" for the Mercury and "gear and pinion" for the Ford. I just came back from The Great River Road Tour an averaged 16 mpg with a 3.54:1 and no Columbia. The driving was on secondary roads that were quite hilly and our average speed was around 45mph.
Tom
|