Slop in front prop shaft

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From Tony Lee:

I've asked a couple of OKA owners about this "problem" and was told it was not worth worrying about, but I would prefer to know why I should or shouldn't worry about it.

The problem as I see it is -
I noticed a small amount of oil on the rear universal joint of the front shaft. Wiggling the shaft radially gives quite a bit of movement (as if the nut holding the yolk has come loose but doubt whether that would be the case). The "spinner" between the front of the transfer case and the UJ is perfectly dry, but the UJ itself has oil on it and even that is strange since I would have thought any oil would get blown backwards onto the spinner and the front of the transfer box..

How can there be a significant movement radially but none axially unless a bearing has failed on the output shaft. If the nut holding the yolk had come loose then if there was movement, then wouldn't it be axial as well.

David gave me this advice --
"Tony, from the small amount of play I doubt that the bearing is stuffed. It runs in oil and supports the main output shaft way inside the box. Mine also has a small leak from the same place which comes
and goes. It's more likely that the oil seal has hardened and oil seeps past and/or there's a bit of wear on the splines of the yoke or gear shaft.
Neither are a big problem but a good oil seal probably grips the yoke and dampens movement. You can check the Nyloc nut but it's done up pretty tight. Until or unless there is a huge amount of movement or clonking when
moving the yoke I wouldn't worry too much about it. The bearing would be difficult to change anyway since it probably means dismantling the transfer box, but the oil seal and yoke looks like they can be changed
more readily (although I haven't done this yet). Paul Nott in Melbourne (0418 125 428) can supply/advise on replacing these items.
These transfer boxes are built tough and I would concentrate on the UJ's and their fixings, and the transfer linkages which are more likely to cause trouble. The diff pinion bearings and yokes are very similar and suffer a lot more stress without failing."

So is David correct and I should put it well down on my to-do list?
--
On a related matter. No matter where I rotate the drive shaft to I cannot get the grease gun on the rear UJ nipple of the front shaft.

Using a standard Mcnaught flexible hose and it just won't quite go on. Closest I get is when the nipple is pointing upward because the gap opens up to the widest point.

The nipple is a straight one and I wonder whether either it should be a bent one instead, or perhaps the cross was put back the wrong way around during previous overhaul?

Any ideas?
March 30, 2010 at 12:24 AM Flag Quote & Reply

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From David Hallandal:

Any "slop" in your shafts should be looked at and I would have it on your "Short" to do list, cos when it fails it will make a big mess. Remove the tail shaft and inspect where the free play is coming from, I would also remove the yoke for a full inspection and repair while there. The nut that holds the yoke on also will adjust the lateral load on the shaft and must be tightened to 100 - 130 ft lbs.

See your service or parts manuals for any more information and what you are looking at.

Are you an LT or XT?

As for the nipple, replace it with a bent one.
March 30, 2010 at 12:26 AM Flag Quote & Reply

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From David Ribbans:

Tony, since they seem to be my words I would obviously have to agree with them.
But if you have any doubts, take the shaft to Hardy Spicer and get an assessment. If the shaft is OK then you know the problem is in the transfer box.

They replaced a bent yoke on one of my shafts when I couldn't get a UJ clip to fit. It wasn't too expensive (around $220 from memory in 2008). But you'll get a balanced and guaranteed item for your trouble.

What you don't want is a broken shaft on an outback track, like we had on the Anne Beadell (DavidH was there at the time). It can cause a lot of damage flailing around (the saddle clamp bolts had worked loose on the rear UJ).

On grease nipples, I've found different guns have different thicknesses of nozzle. A cheapy nozzle might just fit better. A bent nipple might fit but there isn't much space in there when the shaft turns.

David
March 30, 2010 at 12:29 AM Flag Quote & Reply

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From Tony Lee:

Have to start pulling things apart to fix the grease nipple problem so it should be clearer once I can get at the nut to make sure it is tight.

It is far too easy to induce the radial movement for it to be wear of the yoke on the spline, especially if the nut is tight and that is what worries me. Movement at that point should be just about zero - as it is on the three other similar points on the vehicle (which BTW has only done 100,000km, little of which would have involved FWD).

Had a transfer box on a Range Rover fail because of a leaking oil seal and had the diff pinion bearing collapse on my big rig so I know what a little bit of movement and wear can turn into. West of Birdsville doesn't seem the best location to see what might happen.

I'll let you know what I find.
March 30, 2010 at 12:31 AM Flag Quote & Reply

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From Peter Wright:

.....Dunno.....

But when you have the front yolk off the transfer case and replace the seal, add a stone shield to protect the seal if there is not one there already.

I reckon that you can squeeze double seals in there too if you get narrow ones.

Cheers,

Peter
March 30, 2010 at 12:33 AM Flag Quote & Reply

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From Tony Lee:

Yes, when you told me about the stone shield earlier, I figured it is what I called a "spinner". Like a big thick bevelled washer about 100mm diameter and 20mm thick hard up against the transfer case..

Even bought a torque spanner a few weeks ago so with workshop manuals as well, I have no excuse not to do it right. Even the scale of the OKA is manageable compared to my bus. eg 150 ft-lb covers most of the OKA while I need 1000 ft-lbs for the MCI.
March 30, 2010 at 12:34 AM Flag Quote & Reply

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From Joe Baz:

Tony, what transfer case is in yours NP 205 or Rockwell? If you have the NP 205, remove the aluminium cover at the rear of the front output shaft and have a look at the Torrington needle bearing if the yoke nut and splines is OK.

Cheers

Joe
March 30, 2010 at 12:35 AM Flag Quote & Reply

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From Tony Lee:

Well, there you go. Everyone was right and/or wrong depending on one's point of view.

Was a trivial problem at the moment only because I'm not running in 4WD, but one that would certainly have ended up a serious problem.

Nut holding the yoke onto the output shaft was at least half a turn loose, so there was actually axial play as well as the wobble sideways - just that I couldn't apply enough force by hand to get it moving axially.

Just be nice to know why the nut came loose and how long it has been loose.
Now all I need is an 1 1/4 (???) socket so I can torque it up properly.

Thanks for all the advice.
March 30, 2010 at 12:37 AM