Fordson Major Crown Wheel & Pinion

[Dafydd]

Hi

I am currently working on my fordson super major back end, and find the tractor rather slow on the road compared to my other majors. Following reading discussions on here and information from other sources, I came to the conclusion that these are two speed ratios available. These are the 3.3 ratio (Faster, normally found on tractors pre 1960) and the 4.4 ratio, more common on the super major designed for lower gearing, used for cultivation works etc.
I have since stripped a back end of the major with a crown wheel and pinion (3.3 ratio), these being 25 teeth on the crown wheel and 10 on the pinion compared to the 4.4 ration, 25 on the crown wheel and 8 on the pinion.
In order to achieve a faster road speed and to keep the differential lock I decided to opt for the 3.3 ratio. Securing the 3.3 crown wheel were rivets, of which I have drilled and knocked out. On the 4.4 wheel, these are secured by bolts.
From what I have discovered (see http://www.fordson.se/5_Bakaxel_Supleme ... 01-015.pdf ) there was a kit compromising of spacers, bolts and nuts as shown in Fig. 2 of the link to join the crown wheel to the diff.

Does anybody know of any of these “kits” before I get anything machined?
Would it be easier to re-rivet?

Many thanks

Dafydd

[super6954]

Hi
Welcome to the forum
Im not sure if this will help you, In the ford and fordson conversion forum on here Roadless J17 has pictures of his Roadless crawler restoration. He has a picture of his diff and crown wheel being bolted together. Maybe he knows what you need and where to get it .
Regards Robert

[Aussie Frank]

Hi Dafydd,

I hope you read the information on page 9 of the manual link http://www.fordson.se/5_Bakaxel_Supleme ... 01-015.pdf regarding the interchange of Fordson Major and Super Major crown wheel and pinion sets. From the manual it looks like they are different. Super Majors did come out with a 3.5 to 1 ratio back end, but it looks like you can't use the parts out of an earlier Major to change the ratio, they need to come out of a Super to fit.

I would do some more checks before I went any further.

Regards, Frank.

[Dafydd]

Hi
Thanks Frank and Robert for your responses.
Following reading the supplement in further detail, it’s confused me even more.
Is it just the differential assembly parts that are not interchangeable?
From what is seen on page 2, a crown wheel that secured by rivets (as seen on earlier models) are drilled out and bolt kit is used to secure to the diff. If only super major parts can be used surely these would be secured using the same method of twelve self-locking bolts?
Before I get deep into the Super back end will an earlier crown wheel fit onto the diff of the super or will i require a 3.5 crown wheel from a super major?
Does anybody know? Perhaps Dandy Dave would know as seen on a previous thread? http://www.fordsontractorpages.nl/phpbb ... r&start=25

Regards

Dafydd

[Aussie Frank]

Hi Dafydd,

Quoting from the supliment first paragraph on page 9 says it all for me.
"Differential Assembly
Quite apart from the locking device a completely different
differential assembly (Fig. 10) is used on the Super
Major, none of the parts being interchangeable with
those used on previous Major tractors. Generally
speaking, every component is larger than its counterpart
on the previous Major and, in addition, the
number of teeth on the side gears has been changed
from 20 to 16, and those on the pinions from 11 to 9."

I was wanting to know if you could fit a 4.4 diff into an early Major which is the opposite to what you want to do, but it looks like the diff carrier is a different size in between Major and Super. The service parts being bolt on happened so that you could just replace the crown wheel and pinion rather than the whole diff assembly on earlier riveted diff assemblies from my reading of the suppliment. You still need the right size gears for the year of the tractor.

Regards, Frank.

[Dandy Dave]

From what I have re-read...Brian said that you will need to change the carrier with the Crown and Pinion gears to make it work. In doing so you will. "Loose the differential lock." which is a big plus on a Super. Personally, I would keep the differential lock and look for 3.5 gears. Do it once, Do it right. Dandy Dave!