Ah! Jackpot! Page 75 of this catalogue looks like the same animal (not that it seems we can buy any of it)! At least it's a higher resolution photo though.
https://fzth.de/fileadmin/user_upload/broschueren/Hetzel_4WD_Single_Parts_2019.pdf
Ah! Jackpot! Page 75 of this catalogue looks like the same animal (not that it seems we can buy any of it)! At least it's a higher resolution photo though.
https://fzth.de/fileadmin/user_upload/broschueren/Hetzel_4WD_Single_Parts_2019.pdf
Well tonight's update, is that it is more or less finished! I ended up resorting to the angle grinder and a die grinder though. Angle grinder to get the inner races of Bearings 17 and 23 off, and a die grinder to get the outer race of the Bearing 17 that sits inside the big gear on the diff assembly. That was a shocking bit of poor design, with no possibility of getting any kind of puller under the lip.
I've stuck the cooler assembly in place now so I just need to find a seal (20) and I should be able to start re-fitting the bloody thing.
Question for those who have done it before: I've re-assembled it dry and tightened the covers down. I can turn the whole thing on the propshaft pinion easily, and I can turn the input shafts by hand with a bit of a struggle to grip them. Does that seem about right for a re-assembled IRD? I think there's more than 5 thou of pinion backlash, but haven't bothered with a dial gauge. I'm guessing it's probably about double that.
I've stuck the cooler assembly in place now so I just need to find a seal (20) and I should be able to start re-fitting the bloody thing.
Question for those who have done it before: I've re-assembled it dry and tightened the covers down. I can turn the whole thing on the propshaft pinion easily, and I can turn the input shafts by hand with a bit of a struggle to grip them. Does that seem about right for a re-assembled IRD? I think there's more than 5 thou of pinion backlash, but haven't bothered with a dial gauge. I'm guessing it's probably about double that.
Nodge68
Well-Known Member
The IRD should turn pretty easily, but not freely. The bearing pre-load seems good, considering there's no adjustment with shims. Light finger pressure at the end of some loosely clamped Mole grips is about how mine was when I did it some years ago.
OK, that's good. I can easily turn the input shaft with Mole grips. I'll try to nip out tomorrow lunchtime to our local hydraulics place and see if they can sort me out with a seal, then I should be able to start putting it back in.
Well, it's finally all back together! Thank you all for your help and encouragement. I've just been out and done 20 miles and it all feels fine. The various whines, whirrs and vibrations have gone, so I can now moan about wind noise instead! I've left the undertray off and I'll check for leaks / top up as necessary tomorrow.
Lessons learned, if it might help anyone in the future:
1. On a TD4, FL1, there's no point in taking the exhaust off.
2. Taking the IRD pinion housing off before removal helps lighten it a bit and gives you a bit more space.
3. I was lucky because someone has replaced the right hand bottom balljoint at some point and it is bolted through the wishbone, so I was just able to take the bolts out and that let me slide it out far enough to get the right hand driveshaft out of the IRD.
4. slackening the subframe bolts and leaving it hanging on them, gives you a bit more space to get the IRD out.
5. Go for an IRD rebuild kit with a cooler. It really is easy to break them while trying to take them out!
6. IRD bearing kits seem to come with an element of luck! There are shims in the IRD which, I'm sure, ought to be added to or subtracted from, to get the right clearances. I ended up swapping one from the big bearing on the driveshaft end of the IRD to the big bearing on the crownwheel side, and it was only luck that gave me the correct clearance! It seemed to have become necessary because instead of sending two Timken bearings, (which is what the box had in it when I opened it up), they'd sent one Timken and one Koyo. They were the right size, but I think the Koyo was thinner than the Timken.
7. Make sure you get all the seals too (and ideally, the O rings). Mine came with no o-rings so I've reused them and am trusting to luck!
8. Getting the old bearings out of the IRD is the hardest part of the job. An impact gun for the big nut on the crownwheel is your friend. Some of the outer races for the bearings (in particular, the one inside the big diff gear) are very hard to remove. You can't get a puller of any description under the edge of them, or poke them out from the other side. I ended up using a die grinder to carefully grind the inner race away until I'd weakened it enough to relax its grip on the housing.
9. A bearing splitter / separator is a worthwhile investment for some of the other bearings.
10 As Nodge said, it was one of the big bearings behind the crownwheel that had failed. The others (whilst there was some wear evident), didn't look too bad.
I didn't bother stripping the pinion assembly. The bearing in it felt fine and it's another one that needs to be shimmed - plus there's a collapsible spacer in there and you can't get replacements now.
Lessons learned, if it might help anyone in the future:
1. On a TD4, FL1, there's no point in taking the exhaust off.
2. Taking the IRD pinion housing off before removal helps lighten it a bit and gives you a bit more space.
3. I was lucky because someone has replaced the right hand bottom balljoint at some point and it is bolted through the wishbone, so I was just able to take the bolts out and that let me slide it out far enough to get the right hand driveshaft out of the IRD.
4. slackening the subframe bolts and leaving it hanging on them, gives you a bit more space to get the IRD out.
5. Go for an IRD rebuild kit with a cooler. It really is easy to break them while trying to take them out!
6. IRD bearing kits seem to come with an element of luck! There are shims in the IRD which, I'm sure, ought to be added to or subtracted from, to get the right clearances. I ended up swapping one from the big bearing on the driveshaft end of the IRD to the big bearing on the crownwheel side, and it was only luck that gave me the correct clearance! It seemed to have become necessary because instead of sending two Timken bearings, (which is what the box had in it when I opened it up), they'd sent one Timken and one Koyo. They were the right size, but I think the Koyo was thinner than the Timken.
7. Make sure you get all the seals too (and ideally, the O rings). Mine came with no o-rings so I've reused them and am trusting to luck!
8. Getting the old bearings out of the IRD is the hardest part of the job. An impact gun for the big nut on the crownwheel is your friend. Some of the outer races for the bearings (in particular, the one inside the big diff gear) are very hard to remove. You can't get a puller of any description under the edge of them, or poke them out from the other side. I ended up using a die grinder to carefully grind the inner race away until I'd weakened it enough to relax its grip on the housing.
9. A bearing splitter / separator is a worthwhile investment for some of the other bearings.
10 As Nodge said, it was one of the big bearings behind the crownwheel that had failed. The others (whilst there was some wear evident), didn't look too bad.
I didn't bother stripping the pinion assembly. The bearing in it felt fine and it's another one that needs to be shimmed - plus there's a collapsible spacer in there and you can't get replacements now.
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Nodge68
Well-Known Member
I'd change the oil again after a few miles, just to remove any left over fragments that might not be picked up by the magnetic plug.
I think I forgot about those, but it's been many years since I've needed to rebuild an IRD. I don't recall any difficulty with alignments though.
I actually only replaced that bearing last time I did it. I stripped the IRD down, found the numbers on the failed bearings, and simply ordered replacements.
I think the metallic contaminants in the oil will cause wear, but not much if it's caught in time.
That's a whole world of pain, which is best avoided.
Well done on getting it running again.
