Fordson Dexta Rear Axle Oil Leak

Oil is leaking from the left rear axle/brake drum. After a couple of years warning it is now at the point something needs to be done. Beside the lack of brakes on one wheel, the oil on the tyre signifies a reasonable flow rate!

Is there a diagram of the rear hub/axle assembly available? Any pointers on how to tackle replacing the seal(s) would also be appreciated.

I believe the Dexta uses a heat shrink ring to hold the axle into the wheel bearing with the bearing outer race mounted in a removable backing plate on the end of the axle housing. (??) Where is the oil seal? Does the ring have to be removed (read "destroyed and replaced") to replace the oil seal(?) Is the axle locked inside the diff in any way or just a floating spline? (I've dealt with a Mk3 Zephyr before which was a treat with its separate hub and the axle held only by the wheel nuts. The axle seal had to be replaced from within the axle housing which lead to some special tool fabrication but quite a nice arrangement really.)

Thank you for pointers to other information sources

David

During taking the rear axle apart. I did have a problem following the instructions in FO-201 section 75A and photo FO556. Either didn’t I use suitable amount of force or the manual’s information of drilling a 0.25 inch deep hole was incorrect, but after about 2 hours of beating on the chisel using a lot of force at the end. I decided to drill another 0.5 inch totally 0.75 inch (almost thru). Only a few banging on the chisel was needed and the collar was of. Is the manual faulty or did I do I the wrong way?

The markings on the two removed bearings are different. One is SKEFKO K-387 which I think is original (it also has I-116366 which) I think is a FORD #) the other is SKF (made in SWEDEN) CK-387, axel size is 2.25 inch. Some earlier owner have only changed 2/3 of the SKF bearing!
I did have some problem to locate a new collar (my Ford dealer wanted equal US$113 total US$226 for two and a 2-4 weeks of delivery time!!!)

I did bought the collar for MF35/MF135 for <2*10US$ her in Sweden (bepco art#180596M1 made in England thru Olssons in Ellös) it don’t look exactly the same (milled steel instead of milled casting steel and no shoulder) but it will fit perfectly. For information I did some calculations about heating. If axel is 20deg C then heating of the collar (57,00mm inner size) to 325deg C give 0mm spacing and 490deg C give 0.1mm and 600deg C give 0.326mm spacing more heating then that is not to recommend due to nitrogen adding to the steel. I did get that heat by puting the collar on the stowe an placing a AL-pot upside down on top, a small hole thru the pot was used to get a heatsensor tip to the collar (type K) and it was a zero force job to get it in place. A simple aproche would just to watch the collar colur every minute (about 13 minuts with 1000W heat for me) it is starting to change colour from steel to blue at the right temperature.

The local (40km away) Ford shop did help me with changing the break materials for the wheel breaks. During that trip a was aloud to look in the BIG Ford service manual, in that the correct drilling depth is all way thru “when the drill increase in speed it is thru (harder steel in bearing)”. So it is hereby a fact that FO-201 section 75A and photo FO556 is incorrect regarding drill depth.

The generator was lose so after some looking at it I discovered that it was broke a replacement was ordered.

Now my Dexta work just fine. Totally 40 l of oil changed!

Sorry for using bad English langue spelling and so on.

Take the tire and brake drum off and you will see a set of retainer bolts that hold the axle in.

With the retainer bolts out you should be able to hit the axle end with a sledge hammer and the axle will pop out.

There is a shim stack behind the retainer plate so keep up with the shims and don't throw them away with the old gaskets.

It has a lock ring bearing retainer, so just take a 1/4" or so drill and place 2 holes in the lock ring at 180 degrees of each other. Now take a punch or chisel and break the retainer ring off the axle.

When you put the axle assy back together be sure to place the new lock ring so that it grips the axle instead of slips back off.

Ford can get or will have the seals and retainers so that you won't need new bearings, just the locks.

A couple of follow up questions.

I assume one oil seal is in the backing plate, hence the need to get the bearing off. Where is the other? (in the housing?)

The locking ring ... any special handling to get the new one on .. ie heat to a temp or just press ... or is it just obvious once it is all out and a new ring on hand!

Thank you again

Both the seals are on the axle and come in and out with it.

The retainer will be self explanatory once you see it. I use a dull wide chisel and a 2# shop hammer to knock it down tight. I never used heat on one but I would think if you heat it the heat will ruin the new seal. If you have a press that would be better than my hammer approach.

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Thank you for the insights. Will let you know how it all goes ... may take a couple of months as the tractor and I are separated by 250km (150 mile)

Para 75A seems to be the core of the procedure.

Thank you again

David

My one addition to the standard oil seal/bearing replacement was to use a "speedie-sleeve" on the axle where the inner oil seals run.
These are stainless steel sleeves designed to press fit onto a shaft and provide anew surface for the seal. (the Speedie sleeve I used is
numbered CR99212 -for the 2.125 inch shaft, approx 1 inch long, it covered the 0.007 inch groove worn by the old seal)

If anyone wishes to buy bearings, the cone (The bit that goes on the shaft with the rollers in it) is numbered 387 and the cup (the outer bit
that goes in the hub) is 382. These are recognised by the bearing companies and the parts are sold separately.

In Aus the retaining rings were readily available at $Aus80 each, as were the inner oil seals. The outer seals, like the bearings are
standard items that could be brought from a bearing shop!

Getting the bearing off the axle (after removing the ring using a 3/8" hole drilled all the way through ... carefully avoiding the shaft)
required more push than I had. A friend of a friend helped out with a 30ton press that made short work of the obstruction to progress
(about 10 ton was needed to shift the cone on one side, the other about a ton).

Appropriate amounts of heat as suggested by Limpan earlier in this thread made reassembly a treat.

I did have to remove 1 x 0.020" shim to get the axle freeplay to within the 0.004-0.012" tolerance specified ... hope that was just wear
rather than me making a blue!

Thank you all for your help with information to allow the job to proceed.

regards David

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