rear ARB bush size needed.

[weka]

I had a great drive in the Northern Territory of Australia for a few months, but my 306 sedan is in storage now and I am back in New Zeakand. I noticed oil seeping from the arb end brackets, oil because I am running gear oil in the axle. The swinging arm bearings were in good condition so tried this lubrication method (using a bung and breather) to see how it goes. (No leaks from the major arm bush seals, surprisingly)
I notice the standard bushes are described as rubber (not good with oil), and somewhere the end seal described as neoprene.
While home with my lathe, I would like to make nylon bush replacements for the rubber bushes, but don't have accurate id/od and length required.
If someone with the revelant end plate and housing could do these measurements for me I can get busy preparing some for my next trip.
I did get an HT bolt to withdraw the end plate last time but quit when I seen they were on quite tight.
I chamfered the end of the bolt slightly for next time so that it doesn't spread the end of the thread.
I'm not sure how positive the neoprenes end seals are, If the bushes are neat enough fit I could try an inside and outside groove and fit o-rings there as well.
Thanks for any help/advice in this area.
Ron

[weka]

Replying to my own post here, have just returned from Australia where I was able to take off the ARB end plates.
There were dried and broken flat end seals that sit in a 2mm recess (36mm ID 46.5mm OD).
I have temporarily fitted slightly stretched 3mm o-rings as replacements. There is a slight chamfer and they are supposed to be fitted with 1mm clearance so the compression is there but not overly so.
The 36mm outer shoulder of the end plate extends in for 8mm when it reduces to 32mm for the inner sleeve seal.
The bore of the housing is also 36mm causing an endplate metal shoulder alignment for 5-6mm into the housing.
36mm - 32mm leaves 2mm gap for the approx 17mm long cylindrical seal, I may try a row of 2mm o-rings as replacement here one day, but for now just fitted a 1.5mm o-ring under the outer end of the originals, to maybe exert a little outward and lateral pressure to expand it a little.
Oil seeping has stopped so far, no urgency to do any more on it just yet.
Even for a greased assembly this could also equate to less water ingress, those outer seals could be worth checking.
Ron

[Mighty306]

Interesting modification. Certainly beyond my skills (let alone access to equipment like a lathe!). The OEM seals are designed to keep water out, not oil in, so not surprising some mods were necessary. Struggled a bit to fully understand everything you were doing from the description alone. Any chance of some pictures if you ever get it stripped down again?

[weka]

Interesting modification. Certainly beyond my skills (let alone access to equipment like a lathe!). The OEM seals are designed to keep water out, not oil in, so not surprising some mods were necessary. Struggled a bit to fully understand everything you were doing from the description alone. Any chance of some pictures if you ever get it stripped down again?

I initially envisaged a thick walled internal rubber seal , but it turns out it only has a 2mm space to fill, so won't be making a nylon o-ring mount, and just fitting a row of o-rings. I have ordered some 2mm thick o-rings from China, but previous experience has shown the ones that arrive are on the light side of the specs, so it could mean I'll be re-ordering in 2.5mm. Nothing to do on the lathe yet, I guess you could make a spacer and use less o-rings, I think a continuous row of o-rings simulates the original 17mm long seal though.

The major modification for changing to oil was the fitting of a drain bung to one side of the jacking point on the tube, and drilling a smaller breather hole higher up with a dust flap. I have just some tape so far, maybe one day glue on something better or run a smaller breather hose up to a dry place.
The trickiest part is the cutting of a thread into the (not so thick) axle tube for the bung/filling point.
Ron

[welshpug]

its unlikely the oil will get to anywhere important as the bearings are sealed, much in the same way that a grease nipple is pointless.

your time would be far better spent buying a rebuild kit for £90 on Ebay (snr kits) and just doing a proper job.

[Mighty306]

The same thoughts did cross my mind. It's a lot of effort to go to when a beam built to OEM spec should last a good while. Was still intrigued tho.