andyfreelandy
Well-Known Member
How's it going?
Slowly! (but thanks for asking).
Oils and coolant drained, Wheels and undertray off, prop and driveshaft disconnected (Inner tripod joint is mullered, unfortunately). Lower engine stabiliser bar is off (the large rubber is loose in its housing. There's not much play, but it is free to slide from side to side. Not sure if this is normal? Stabiliser bar mounting is off the IRD. I've also taken the pinion and its housing off because I thought it would make the cooler hoses easier to disconnect. At least all the teeth on the pinion (and those I can see on its mating gears) look fine. The bearing feels tight, but a bit "gritty" - almost like a bike wheel bearing that's been over-tightened. Not sure if they're supposed to feel like that? I still need to take off the cooler hoses and the mounting bracket holding the top of the IRD, then it's just the four big bolts holding it to the gearbox.
That's about as far as I've got really. I got an hour or so on it last night and then another hour this evening, but have been ferrying kids to and from sporting activities / parties all day, plus youngest sprog has bought some second hand cycling shoes on eBay and the screws holding the clips on to the bottom of them have seize in their inserts, which then ripped out of the fancy carbon fibre soles...
..this is going to take a while, I fear...
Is anyone aware of any good "how-to" articles online for rebuilding the IRD itself? Do bearings need to be shimmed / preloaded or that sort of thing?
Nodge68
Well-Known Member
Only use an OE (GKN) replacement drive shaft.
Normal, but not correct .
The bearings should be smooth and grit free. The gritty ness is due to metal in the oil. Bearings not being replaced, need a thorough cleaning.
The IRD goes back together, in the reverse sequence of taking it apart. There's no shims or spacers in it. It just goes back together as it came apart.
Might see if I can find a good second hand one - this bloody car's coming up to costing me more than it's worth!
Ta. Worth getting a new one? (Or are they happy like that pretty much forever)?
Fair enough. It'll all be coming apart when I get it out and I have bought all the bearings, so I'll replace the lot anyway. However, I didn't get any O-rings in the kit. There's certainly one big one on the propshaft pinion housing. WOrth getting new, or will they go back together and seal OK?
That's amazing!! All the machining tolerances must be absolutely incredible! I can remember trying to rebuild the old Salisbury diff on my old Scimitar many years ago. Bloody horrible job, involving messing about with engineer's blue, assembling with various shims and the taking apart again to look at the pattern to get it meshing correctly, then collapsible spacers to get the right preload on it... nightmare of a job! Are there any fastener torques I need to be aware of, please?
The next question, I guess, is how to get the bearings out? For the outer races, are they just a press fit? Do I bash them out with a drift? How should I press the new ones in? With a drift again, or would a press be a better bet?
Also, how do I get the inner bearing races off their various shafts - just hammer them again? Is it wise to use heat?
Lastly, although all the shafts are out, I'm still puzzled as to how this big gear comes out? I've undone the nut on it, but what next? Just bash the other end of it?
Also, how do I get the inner bearing races off their various shafts - just hammer them again? Is it wise to use heat?
Lastly, although all the shafts are out, I'm still puzzled as to how this big gear comes out? I've undone the nut on it, but what next? Just bash the other end of it?
Nodge68
Well-Known Member
The bearings are a press fit.
You can tap them out with a brass drift.
I use a cheap bearing puller.
Moderate heat won't hurt anything, although isn't much use either.
You need to get to the rear of the crown wheel, so it can be tapped free. Once out, the shaft with the large gears comes out the opposite side. It uses 2 bearings as the support and thrust bearing.
It sounds more complicated than it actually is.
Thanks again. I shall renew my attach on it with a suitable big hammer and a drift. I've ordered a better bearing puller, as I only have a "Mickey Mouse" one. Might not be until the weekend that I get a chance to do more on it though.
Another question, if I may? The VCA was replaced by the previous owner barely 12,000 miles ago (2 years in terms of time, as they didn;t use the car much). I've no idea whether a genuine part was used, but the bill that came with it was for £280 fitted. Ever since I've had the car, it slows slightly when coasting on full lock. That's subjective, I know, but whilst there is more drag than with a 2WD car pon full lock, it's not a great deal more. If I let the clutch out slowly (in 1st or reverse) on a full lock, the car will happily drive round in circles with no throttle input at all, just the idle speed control. I've heard folk say that if the car feels like the brakes are binding on a lock, it's a sign that the VCU is seizing, but is even a small degree of bind unacceptable? (Don't want to trash this IRD as soon as I refit it)!
Another question, if I may? The VCA was replaced by the previous owner barely 12,000 miles ago (2 years in terms of time, as they didn;t use the car much). I've no idea whether a genuine part was used, but the bill that came with it was for £280 fitted. Ever since I've had the car, it slows slightly when coasting on full lock. That's subjective, I know, but whilst there is more drag than with a 2WD car pon full lock, it's not a great deal more. If I let the clutch out slowly (in 1st or reverse) on a full lock, the car will happily drive round in circles with no throttle input at all, just the idle speed control. I've heard folk say that if the car feels like the brakes are binding on a lock, it's a sign that the VCU is seizing, but is even a small degree of bind unacceptable? (Don't want to trash this IRD as soon as I refit it)!
GrumpyGel
Well-Known Member
There is always an amount of 'braking effect' - even if its not perceivable - and different people's perception appears to be at different levels.
It sounds OK, but you should really do the One Wheel Up Test to see what sort of timings that gives. Video shown here...
https://www.landyzone.co.uk/land-rover/tests-new-freelander-1-owners-should-do-on-their-car.312863/
Do you know who the £280 bill was from? I doubt it was a new genuine GKN VCU - they are usually priced a bit more than that, but it does sound like the price of a recon from someone like Bells.
It sounds OK, but you should really do the One Wheel Up Test to see what sort of timings that gives. Video shown here...
https://www.landyzone.co.uk/land-rover/tests-new-freelander-1-owners-should-do-on-their-car.312863/
Do you know who the £280 bill was from? I doubt it was a new genuine GKN VCU - they are usually priced a bit more than that, but it does sound like the price of a recon from someone like Bells.
OK, thanks. I'll try that when I next get some wheels on it! Don't know if it was a genuine VCU or not. Will try to have a look next time I'm under it.
Right, well I'm starting to reassemble it all now. There was one shim behind the inner bearing on the crownwheel. Both bearings that came out were Timken, but in the repair kit, the inner was a Timken and the outer, a Koyo. I've pressed the crownwheel into its bearings and it all looks nice and spins nicely, but does anyone have a torque for the big nut in the end of that shaft, that goes up against the crownwheel?
I found this article:
https://www.quaife.co.uk/wp-content/uploads/2018/08/LRO-Sept-2018.pdf
which suggests 184 lbft (!) That seems like an awful lot to me! Is that what determines the preload on the bearings? It doesn't look like there's a step in the shaft that will stop them carrying the full induced load from that torque!
I found this article:
https://www.quaife.co.uk/wp-content/uploads/2018/08/LRO-Sept-2018.pdf
which suggests 184 lbft (!) That seems like an awful lot to me! Is that what determines the preload on the bearings? It doesn't look like there's a step in the shaft that will stop them carrying the full induced load from that torque!
Nodge68
Well-Known Member
The nut is large and is done up tight. It takes a lot of load, as it's keeping the crownwheel from parting company with the rear output pinion.
From memory, the bearing pre-load is set by close tolerances, so the nut shouldn't lock it up. It's been a while since I rebuilt an IRD, so my memory is a little foggy on it.
Thanks. It's looking like I've done something wrong, I think. I put it in and torqued the nut up (well, I only got to 150lb, but just thought I'd try the pinion in at that). Not good! The pinion assembly hasn't been stripped yet, so it's just as it was when I took it off. When I push it over the studs into position, I can't get it to mesh properly. There's about a 5mm gap between the two housings, and already the two sets of teeth are binding up. It's as if the crown wheel is now in a different position (too far away from the oil cooler end / too close to the pinion centreline), compared to where it was before I stripped it. I can only see one shim in there and it was a ring about 1mm thick, between the bearing outer race that is closest to the intermediate shaft (40 on the drawing below) and its housing. Looks like No. 39 on the drawing. Would anyone know where I could get hold of other shims and a crush spacer (37) please?
Nodge68
Well-Known Member
Is bearing 40 the correct way round?
I've never needed to pull the pinion housing apart, as the bearings don't seem to wear. I've just flushed them through with WD40, then oiled them.
Yes, that's definitely the right way round. They're taper roller bearings and they sit back-to-back, so they can't work if one's in the wrong way round. I'm wondering, however, if I've got the wrong bearing in. The boxes that came in the kit aren't labelled. I'm jus ta bit surprised that I've got one Timken and one Koyo, whereas two Timkens came out. They all seem to be slightly different sizes to prevent you getting the wrong ones in the wrong places though. I think that's my next job - check, just in case I've done something daft.
That also seems to be true in my case. The pinion bearing assembly feels "ok" to just turn by hand. I was thinking about leaving it because (a) I didn't want to disturb that crush collar and (b) , if it does need changing at a later date, I can do it without taking the whole IRD off.
Nodge68
Well-Known Member
I replaced each one in turn last time, so I didn't mix them up. Marking each one I'd changed with a sharpie once it was replaced.
It's difficult to set the correct mesh, without measuring very accurately with a DTI and surface plate. That's why I've never done it on an IRD.
andyfreelandy
Well-Known Member
Good diagram, where did you get it please? Are there other parts shown exploded?
The image appeared in this forum post:
https://content.invisioncic.com/r226025/monthly_10_2011/post-34135-0-81592000-1319821871_thumb.jpg
Can't see any others though.
I wish I'd done that, but of course, once the shafts were out of the casting, I set to and belted all the outer races out of it and then washed it in the parts washer.
However, the good news, is that I think I'm sorted now. I can't get those two bearings in the wrong places. One has an ID of 40mm and the other, and ID of 41, so that the bigger one can go on the end of the shaft closest to the crown wheel without having to be pressed over a surface of the same diameter for the other bearing. In the end, I belted everything out again and swapped the spacer from the end it came out of, to being under the outer race of the other bearing (the one nearest the crown wheel. This meant the bearings were still the same way round as I had them, but the whole assembly sat nearer the oil cooler end of the IRD. As a check, I put white marker on the other end of that shaft (where he needle roller bearing goes), and put the end casing back on, then spun it round a few times and took it off again. The needle rollers made a track in the white marker, exactly where they'd previously been running on the shaft (so that was a good sign)! I then shoved the pinion in and tightened it on three studs and it meshed nicely. Like you, I didn't bother with a DTI, but it had a darned site less backlash than before I replaced the bearings and it all felt nice without being tight. I think I'm going to go ahead at that!
Just doing the needle roller and right hand driveshaft bearings now.
