4600 Changing Half shaft Oil Seal

[awemawson]

How much do I need to strip down to replace a leaking half shaft oil seal on my 4600?

The 'book of words' I have (I&T Shop Service FO-41) is coming from the direction of stripping the entire back axle which I don't want to do if I can avoid it.

Also what retains the half shaft? Nothing seems obviously positively holding it from sliding out in the exploded diagram that I have

[scoobyjim]

Take hydraulic top cover off. Remove nuys from final drive. Slide half shaft out. Romove bearing then seal.

[awemawson]

Thanks for that ScoobyJim. Doesn't sound too bad EXCEPT I have a cab on top of this lot

I'm rather surprised it's possible to get at the inner end of the half shaft through the hydraulic top - they seem quite a way apart

[scoobyjim]

If its just the old ford cab then leave it on. no need to touch that. If its a q cab youll probably have to take it off first if you cant get to the cover. The shaft will be aprox 4ft long once removed. In order to save the bearing for damage once removed you may have to make a 4ft puller as its very difficult to get to the bearing with a punch.

[The Swanndri Guy]

Correct me if I'm wrong, but on a 4600 you will have to remove the axle housing, remove the plantary gear set to get to the half shaft, so it can be removed so you can replace the seal. Like Kiwi Kev did with his 5000 about 18 months ago

[awemawson]

Yes I think that you are right The Sawnndri Guy.

I bit of web research tells me:

A/ Support centre of rear axle
B/ Independently support Q cab
C/ Remove Wheel
D/ Disconnect Brake linkages etc
E/ Remove cab mounting
F/ Unbolt ring of bolts holding axle sub-assembly
G/ Withdraw from centre housing
H/ Remove Brake assembly and planetary gears
I/ Remove cap screw and retainer from inner end of half shaft, (also I think a spring clip ?)
J/ Withdraw Halfshaft
K/ Knock out oil seal & replace
L/ Put it all back together

But this is just theory at the moment, and I'm undecided whether to do it myself or get my local ag engineer to do it as I'm not sure if I want to be playing with big heavy lumps at my age. Trouble is, if I use the Ag engineer, although he is good he tends to let other jobs take over and things stay with him for weeks on end. But if I do it myself it saves cash which can go on a new pair of tyres

[The Swanndri Guy]

Awemawson, another thing to consider with your leaking axle seal, is how is your exturnal hydraulics return is hooked up, does it use the fill plug? ie has the vent on the fill plug been removed?, so without the vent, the oil heats up and builds up pressure in the rear axle housing and vents out the path of least resistance, the axle seal Just a though as my 4000 does this sporadically. TSG.

[awemawson]

Good thought about the vent, but it happens cold and static - park up and she drips away nicely

The Hydraulics don't use the filler plug as it seems to have had dual circuit remotes fitted from new - the pipes emanate from the dual spool valve.

[scoobyjim]

Ah yes, your right about removing the housing

[The Swanndri Guy]

Ah yes, your right about removing the housing

I think the quote your looking for is, "I'm never wrong, but I stand corrected"
(I'm not perfect either )

[awemawson]

Well at long last I've changed the oil seal.

I started taking it off using my fork lift arm to take the weight but it was far too cumbersome to put it back single handed that way, so I made up a wooden cradle for it to sit in and used my workshop hydraulic trolley to manoeuvre it back in. My half shaft had wear on the seal surface - mainly on the outer lip of the axle seal, and I would have put a repair sleeve on it but the relevant size is on 5 weeks back order - it's an SKF 99326. I have one on order but so far the leak is ok

I made up a 5/8" UNC 'guide pin' to line the trumpet up more easily and it worked a treat. Just a 3 1/2" length of 5/8" mild steel with a 5/8" UNC thread one end to screw into the axle casting, and a short taper on the other end to guide the trumpet into place. I also cross drilled it 6 mm to make removal easier

A few pictures will perhaps help others in the future.