JCB 3CX Gearbox Shaft seal leak?

[Classic3CX]

Hello there,

So I’ve noticed a small leak on the gearbox, to what looks like the shaft seal. I know there has been similar posts about gearbox oil in the past but I’m wondering if anyone has had this issue before and how easy it is to do/things to look out for?
Possible parts required? (new seal for sure).

As you can see from the photos below they have used an ATF oil which I was going to drain and replace anyway so it’s all fresh.

[essexpete]

Looking at the era of your machine I think your machine would be spec an ATF with the whole transmission using one oil. Check on one of the oil websites.
With the seal I don't know the machine at all but you will need to check that the shaft is not moving in and out excessively or that a groove has been worn.

[Classic3CX]

Sorry yeah it’s 1987 3cx, 4 geared, 4WD. Yeah I’m guessing it’s just worn so will need a new one that’ll fit tight to it

[Classic3CX]

I presume mine is the one with a Dropbox as well in terms of spec, see photo below:

[Jeremy Rowland]

From the photos you've posted it looks a straight forward job? Drop the prop, undo the nut that should be holding the flange in place, remove the flange, check that the seal area on the flange is not badly worn, prise out the old seal, get a new one, put some Loctite or silicone on the outer diameter and carefully knock it into the housing. Refit the flange and prop, after lubricating the area on the flange where the seal runs with a bit of grease, then top up the oil.

One last thing before you take off the flange check that there is no play in it (up and down) also check a manual to ensure that it is not pre-loaded, make sure that if there are any pre-load bearing shims behind the flange that they are okay and go back in when you put it all back together. I don't think there should be any but as I'm no JCB expert I am just trying to help you what to lookout for.

Jeremy

[Classic3CX]

Yeah that’s the kind of thing I was worried about to see if anything needed aligning/checking/look out for on the gearbox side, but yeah it does look like a straightforward seal change.
Thanks for the info/guidance as well

[Classic3CX]

It’s looking like this one anyway

[Jeremy Rowland]

At an initial glance it appears to be straight forward the shafts look like they are supported by roller bearings not tapered roller bearings so no pre-load, perhaps the hardest part of the job will be undoing the flange nut but if you have a half decent air ratchet you should be okay.

Jeremy

[Classic3CX]

Would anyone know the suitable modern oil to put back into this for the application? The pink stuff I presume is moisture/condensation in the ATF, just wondered if anyone uses a certain type of oil for these machines now. Cheers

[essexpete]

I would go on an oil Web site with a machine application tooll.