I’m rebuilding my 1973 Eldorado and I’m about to put in the swinging arm. I’ve replaced the three bearings and the uj has been overhauled by Nigel. I’ve read Guzziology and decided to put 30 ml of gear oil around the uj. The carrier bearing is sealed. I’ve got a nice fit from the uj to the carrier bearing and installed it using a bearing fit glue. I put the rubber boot onto the swing arm and poured the gear oil around the joint. So I didn’t expect the gear oil to then drip through down the swinging arm shaft onto my feet! Is something adrift or am I missing the blindingly obvious.
Thanks Ian
I’ve never bothered myself but some people spray chain oil or smear a really thick grease onto the uj.
Thanks I just didn’t expect the oil to seep from the uj side of the bearing to the shaft side and consequently I’m wondering if I missed something.
Cheers Ian
Most likely, although the support bearing is sealed, the actual seals are little more than dust covers really so the oil is seeping through the edges.
As per Ian I didn’t usually bother either just grease the splines, as the needle roller bearings have seals too so never sure how much oil could actually get in. And if it did would it wash out the grease?
I’ve never bothered treating my UJs with anything, though it does seem odd that it’s all leaking down.
BTW - I always have better luck plugging the shaft back in by mounting the UJ on the g/box output shaft first, then offering up the s/arm with no shaft in it - but using a long rod pushed up there to get the UJ end orientated to plug into the bearing. Then assemble from there.
I doubt that will work well if you have to hammer the UJ into the support bearing because it’s a tight fit. Which it should be. 
Thanks for the response I had the same thoughts as Mike about the oil seeping through the sealed bearing, so I tested the old one and the oil hasn’t leaked through! Maybe the new one does however I’m reluctant to take the new one out especially after I’ve gone and stuck it in. I think I’ll have a go at putting it back together.
Cheers Ian
I assume the loop frames have a similar rubber boot between the swing arm and gearbox end cover like on the later Tonti models. Any oil you pour over the UJ will just drip off and collect in the boot, in fact you would need the boot pulled back to pour the oil over the joint.
I take mine out for a check at the same time as I change the gearbox oil. I drain the gear oil into a margarine tub and leave the UJ soaking in it overnight on the hope some of the oil will get into the needle rollers to keep them lubricated.
Greasing the splines is always well recommended.