Front Diff Removal

[AustHaflinger]

Now that I have hopefully fixed my carby issue I can now move onto the next major issue that I have - bearing noise somewhere in the drivetrain - most likely the front diff. The noise has been there since I have had the Haffie, I have now covered 1800km in the past 8 months and it is not getting worse but is there.

When I bought the Haflinger I found the oil seal on the hub end of the front swing axle was blown letting out diff oil (not the greatest design aspect of a Haffie) and I suspect the previous owner had driven it a few times with low diff oil ad maybe no oil. The noise sounds like it is coming from the front diff but could also be coming from the hubs - I have had the front right hand hub apart this time last year and all seemed OK - the front left one needs new kingpins (which I have) but has not been pulled apart as yet.

So that is a bit of the background.

Now my question to those who have pulled out the front diff. In removing it - is it best to take out the front diff and front swing arms and suspension as one complete unit and then dismantle on the garage floor, or with everything in place in the car, remove the swing arm fulcrums to disconnect the swing arms and remove the driveshafts and whem these are clear of the diff, unbolt the diff from chassis tube.

Are there any other tricks to look out for that might not be covered in the manual.

Thanks

Garry

[heinkeljb]

If it were me, I would pull the hubs off. Remove the drive shafts at the diff ends. Then disconnect the prop shaft tube and any other connections still holding the diff to the platform. Lastly, remove diff from the "T" piece.

I would do it this way as the least amount of weight to have to manhandle at a time.

You should be able to disconnect the swing arm fulcrums and other junk, disconnect the prop shaft and remove the diff from the "T" piece, but that leaves the hubs hanging from the platform and unless you tie them up they might strain on things that it would be better not to strain!

Which ever way you do it, take lots of pictures - maybe buy a cheap camera so it doesn't matter you have oil hands! I shall no doubt have to do the sane job on Lurch at some point....

John

[Julian B]

I'd agree with John, and can't see that there is much / anything to be gained by removing it all in one go. The weight will make things much harder. I might be tempted to put it back in one piece, but at least at that point everything is clean and known to be working etc.

One other thing that I would add is that it can be quite difficult to remove the swing axle pivot pins. We struggled manfully with a large screwdriver and all we did was graunch the slots. So we cobbled together a wide flat bit of metal and an old "socket" and this made things much easier. (This photo makes the blade look pretty awful, but in reality it has proved to be fine.

Don't forget that you can buy several different sizes of "over sized" pivot pins - you may well want to replace what you have with slightly larger ones if you swing axles suffer from any excess play ...

[AustHaflinger]

Thanks - John and Julian - dismantle first it is then - I know how to do that. Julian my fulcrum are all moveable so I should be right. In doing this job I am hoping to stop diff oil leaking out of the fulcrum pins. These oil leaks have been the bane of my Haffies life - the pins leak even though they had new rubbers. I cannot understand why the Austrians designed them that way rather than having them lubricated by grease via grease nipples.

Thanks for the heads up.

Cheers

Garry

[heinkeljb]

Presumably they thought, "there is oil there already, all we have to do is make a path for it"!

I wonder how stressed that part gets, normally an "O" ring should be enough to seal oil in or out. The amount of movement isn't high so wear on the "O" ring should be minimal, so there must be some other reason why they leak. Presumably, compression of the "O" ring when you hit a bump / pot hole?

John

[Julian B]

Sorry to be a bit dim here, but what oil is leaking? I have always assumed (dangerous, I know!) that the o rings and rubber caps were little more than dust caps (i.e. preventing crud from entering the pivot point and causing abrasion). The diff & drive train lubricating oil does not really contact these pivots.

Or have I missed something?

[heinkeljb]

Reading somewhere, I think the yahoo site, that there are a couple of holes in the fulcrum pins which are filled with felt or some thing similar (it goes hard and stops the oil from being wicked to bearing surfaces) and you need to make sure they are in good order.

Like you making an "assumption", if the felt is removed in order to make sure oil gets to the bearing surfaces, maybe the "O" rings can't stop the oil leaking ?

I might be totally wrong about all of this, although I am sure I read about the holes in the pins. I can't think why else there would be holes in the pins.

John

[AustHaflinger]

Yes there are small holes that take oil from the diff into the fulcrum pins - they supposedly have wicks in them to dribble the oil to the required area. The O rings/seals are designed to keep the dirt out and oil in. Likewise I am not sure of the design wisdom of having the swing arms full of diff oil - another place to loose diff oil and substantially increases unsprung weight. A better design would have to simply have output shafts on either side of the diff with external CVs like most cars have and an exposed drive shaft to the hub with the CV on that end. The swing arms would not need to be as heavy and I lot simpler to work on.

Thanks

Garry

[AustHaflinger]

Ok - I am now at the point of wanting to remove the front diff and am looking for tips and advice - in particular things to look for.

Hubs are removed but swing arms still in place. Speedo disconnected, all linkages removed. 4wd is not selected nor is the front diff lock.

So the intention is to support the front of the chassis tube, remove supporting nuts/bolts that hold the sides of the diff to the front of the chassis and then undo the long nuts/bolts that hold the diff/4wd housing to the front end of the chassis tube.

The pull the diff forward.

I have looked at the workshop manual where the front diff removal process is part of the body removal process so some actions are not needed.

Is it as simple as that or are then some tricks for new players. I have not listed every little action but an after something that I have to specifically look for or be wary off.

Thanks

Garry

[pathfinder700ap]

Hi Gary,

I think it might be easier to pull the front axle with the whole cross member out. I.e. undo the four bolts that connect the platform to the chassis. Then insert some smaller pins instead of the bolts into the platform holes at the rear axle (so the platform cannot slide away). Then you can slightly lift the platform at the front end and pull the whole front axle out (of course, my description does not include undoing all the other connections etc...).

I think a friend of mine has done it that way and was happy with it. It should also allow you to re-assemble the whole front axle outside of the Haflinger and then put the whole assembly in again when completed.

Regards,
Constantin

[AustHaflinger]

Thanks Constantin - I had a close look and other than unbolting the front of the body and removing the brake lines there is not a lot extra involved

However already undid the front mounting bolts and loosened the ones around the tube.

I think though that if I had not already pulled the hubs off and already taken other bits off I would have used the method you described.

All good information to be filed away for further reference.

Thanks for your input - anything to worry about when I actually pop the diff assembly off the front of the chassis tube?

Cheers

Garry

[Goatwerks]

There are 2 threaded holes on the tube mating flange, use a medium length 8x125 bolt to push diff off of tube mounting. Make note of gasket locations, they are part of shim calculations on the pinion to diff housing.

[AustHaflinger]

This is where I was at when I read Constantin's post - nuts removed or loose on the tube and front brackets disconnected.

The housing came away from the tube without any issues.

The bearing in the tube - one of my prime suspects for the noise - does seem a little rough when the shaft is turned by hand but could be the bearing at the other end at the back of the car. I will replace as a precaution - I suppose it will be hard to get out.

Garry

[AustHaflinger]

There are 2 threaded holes on the tube mating flange, use a medium length 8x125 bolt to push diff off of tube mounting. Make note of gasket locations, they are part of shim calculations on the pinion to diff housing.

Thanks Jim - as you can see above the diff just popped off. On seeing your post I went back and had a look at the tube end - yep spotted the threaded holes but they were full of dirt so I did not notice them when the diff housing was coming off. The holes are in the 11 and five o'clock position.

Thanks for the tip - if the diff had not come off I would have needed to use then to prise the diff off.

Cheers

Garry

[AustHaflinger]

HELP

I need some help in working out how to remove the front bearing in the chassis tube.

The handbook 4-7 says

"Remove circlip and spacer" - done no issues.

"Remove bearing flange by means of an extractor" - The bearing flange is the bit with the cutouts at the side that the bearing sits in. the bearing flange then sits inside the the end of the tube.

The handbook doesn't seem to say what the extractor is

As the flange does not appear to be threaded in I tried levering it out from the side - the flange moved about .1mm out but no further so I assume is an interference fit to the tube. I then put a puller on the little ears at the side but even with a far amount pressure the flange did not move - I stopped as I was concerned I would cause damage.

So my question to the experts is how do you remove the flange and bearing with normal everyday tools?

Also, with the rear diff and gearbox in place can you pull the drive shaft that runs through the tube out (and put it back without issue) from the front of the tube. If you can I will replace the the centre bearing on the drive shaft.

Thanks

Garry

[Goatwerks]

The tube must be free at both ends. After removing snap rings(circlips), use a 3 jaw puller to push the shaft each way till it releases bearing flanges. You could substitute a hammer and block of wood and just knock em out.

[AustHaflinger]

The tube must be free at both ends. After removing snap rings(circlips), use a 3 jaw puller to push the shaft each way till it releases bearing flanges. You could substitute a hammer and block of wood and just knock em out.

Thanks - so I take it I cannot replace that bearing in the pic without taking the entire chassis tube out

Garry

[Goatwerks]

It can be done at the end, but it requires a little finesse. With the snap ring and spacer removed, find the slots in the spacer and use a 2 jaw puller or 2 large screw drivers/ short stout pry bars to Gently wiggle the spacer off the shaft. The hard part is re assembling it without damaging components at opposite end. The seal is in the spacer behind the bearing. The lube inside the central tube is only for the center shaft bearing.
Look at parts book shaft breakdown for best insight.

[AustHaflinger]

Thanks Jim - sounds like many over designed aspects of these vehicles - why the flange is not simply screwed in is beyond me.

As I said I have tried levering and using a two jaw puller and I am sure I will break the little ears off if I use any more force.

Decision made - it will have to stay there and I hope the bearing is actually OK. At a later stage the gearbox needs to come out as there is a noisy bearing in there (noise when in neutral with foot off the clutch - goes away when clutch depressed) so as I now know how easy it is to get the front diff off, I will pull the centre tube and shaft then.

Now to the diff and lets hope the noisy bearing I have is there and not in the chassis tube.

Thanks for your input and advice - I appreciate it.

Garry

[Goatwerks]

It will be either the pinion bearing or the ring gear side carrier bearing, Make sure the gasket is replaced between pinion and diff housings.