Radius arms. which side is up - IRS First Time Rebuild

(Frank Andersen) #142

The preload refers to the bearings, Mark - and the ‘modern’ tolerance is 0,001 - 0,003"…

So as I interpret it; you need to add, say, 0,007" of shims - but it absolutely useless to measure the preload before the hub is mounted and torqued…

xj6 85 Sov Europe (UK/NZ)


(Mark Lee (Pay Pal Patron)) #143

Alright I finally got the parts and the tools to start putting the IRS back together. I’m gonna have to weld up some rust holes in the cage as well as cracks in the bottom plate. So I’m cleaning the years of grime I noticed the bottom plate was nicely dished, and the lip cracked. Obviously, from some yahoo jacking the car up from the plate.

So I was about to straighten but just as I started looking for hammers I stopped and thought about it. If I get the panel straight again, then the other stuff may not line up. like the cage. I’m a bit concerned about getting the differential aligned properly in the cage or getting the bolt holes to line up.

Is this a valid concern?

I’ll be putting up more videos in the next couple of weeks.



(Andrew Waugh) #144

Not really, Straighten it and when you go to refit it (at the end of the IRS rebuild) use a file to adjust any of the 6 holes between the cage and the tie plate which are wildly out.

If it’s been so distorted that the 8 holes for the diff mounts are out then it’s taken one heck of a hit.

I flatten and planish them with a hammer before refitting if they’ve only got the usual apprentice marks, but if there is major distortion and lots of lip cracking I usually replace them.

You can also welded a “V” shaped length of 5/16" rod to the bottom, with the ends of the legs extending close to the diff mounts, and the bottom loop extending past the rear lip (With the lip ground away to allow the bar to lay flat). This sacrifices about 1/8" of ground clearance, but makes a nice rear towing loop.


(Mark Lee (Pay Pal Patron)) #145

Thank you Andrew, I will be planishing my panel into submission. I like the V for a tow strap. Not that any of my XJ’s have hitched a ride. Ummm… Let me rephrase that. All of my XJ’s have hitched a ride. The SWB Series II has a frequent flyers card with the local tow company. :slight_smile:


(Mark Lee (Pay Pal Patron)) #146

Well making progress! I’ve got the bushings in the Radius arms, arms all painted, sanded the rust off, and fixed some broken welds around the small end. I’ve put a video together installing the bushings.

It’s long. Really long. As a matter of fact, I took out about 20 minutes of me dropping stuff, not getting the bushing started straight, having to pop it out again - well because I installed wrong AGAIN! (for the love of God!). Here’s the radius arm install video and yes, that is the kitchen, and the warden was out on her rounds. Safe for now.

Anyway check out the video, Tomorrow I will be shooting the pressing in the Universal Joints in the half shafts. The shims for the carrier(s) are on back order. bad words are springing to mind. Anyway,

Making progress??!?


(Aristides Balanos) #147

Nice video !
And a three car Garage!! lucky you…


(Mark Lee (Pay Pal Patron)) #148

Thank you! For the kind words on the video. I hope its informative to some; and not so much a case of pointing out the obvious.

Unfortunately it’s not a true three car garage. The bay where I parked the Series I (in the video) is about 1/3 of a bay. That’s where I do my welding and keep the car washing stuff. The laundry room took up the rest of that bay.


(Mark Lee (Pay Pal Patron)) #149

New video on YouTube How to assemble the IRS half shafts. It’s another long video about 20 minutes. I do have a question about it; and that is which grease fittings to use. the angled one or the straight type. The grease fitting hole is offset; meaning it’s not coming straight out of the crotch of the trunnion.


(Mark Lee (Pay Pal Patron)) #150

In the half shaft video, I’m at a bit of a quandary as to replace the grease fittings with angled ones or install the straight fittings. The location of the fittings is off center to compensate for a tight squeeze in the corner of the trunnion.

Open to suggestions.



(Robin O'Connor) #151

Go for the angle zerks to be sure of access.


(Mark Lee (Pay Pal Patron)) #152

I’ll pick some up. Thank you


(Mark Lee (Pay Pal Patron)) #153

I’m reading through the Green Bible, in the section about setting the preload on the fulcrum tapered bearings; the book is suggesting I make a “simple Jig”
"A simple jig should be made consisting of a piece of steel plate approximately 7in x 4 in x .375 in. Drill and tap a hole suitable to receive the outer fulcrum shaft. Place the steel plate in a vice, screw the fulcrum shaft into the plate and slide oil seal track onto the shaft"

Does anyone have a picture of the “Simple Jig” the Book is on about? I’m assuming the “Jig” is for setting the preload on the fulcrum bearings inside the hub carrier as well as get the weird 4 piece oil seal in place?

I’m trying to wrap my head around what they’re on about. My pea brain is visualizing a 3/8" plate that is 7 x 4 " with a tapped hole in it (someplace). Then some how putting it in a vise and screw the carrier onto this steel plate. Is it that simple? Shouldn’t the steel plate require surfacing to insure it’s flat so the preload is accurate?

Maybe it’s just me, but couldn’t one set the preload using the fulcrum arm in a vise? Speaking of fulcrum arm, I noticed mine has a bit of a “seal” aka gritted seal wear pattern shouldn’t that be surfaced as well? so the mating bits will last longer? If that’s the case then one should have a variety of shims on hand. Right?

Thanx in advance


(Mark Lee (Pay Pal Patron)) #154

I’m back on it (for now). I’ve got a couple of questions. I’ve assembled one of the hubs, and for the life of me, this just doesn’t seem right. I did a video explaining my quandary.

  • Not on the video is how to prepare the felt seal.
    I squished as much grease in it as I could, but when I bolted it all together as a test fit, it would appear the grease squished back out. Is there a better way? Oil or some sort of magic lube that sticks to felt and keeps everything else out?
  • on the same note of felt seal, in my little pea brain I would think there would be some sort of cover to protect the felt grease (or is it an oil seal, meaning I should soak it in oil) seal. because with the orientation of how it came apart, it would appear that all of the moisture & dirt would wick into or onto the felt contaminating the bearing resulting in an eminent failure. either that or have a team of lube technicians following you around and lubing the fulcrum shaft every time it you park the car.

Am I over thinking this? Have I and the PO put the fulcrum kit back together wrong? Please review the linked video. It’s short I promise less than 2 minutes - it’s just for the J-L members, or should I say, “Members Only” It’s nothing fancy no stupid tricks like light sabers or anything.

Thank you in advance


(Mark Lee (Pay Pal Patron)) #155

Just an FYI, I picked up some angled Zerks and just my luck by the time the fittings were tight, the angle was pointing to the center of the u-joint. I’m still giggling over that one. I know I have some rubber / stainless washers that will fit over the end of the Zerk. that should point them in the correct position or closer. I’ll install them as soon as I find them. I have all these fancy plastic bins and these wonderful washers aren’t in the bits. Go figure.


(Frank Andersen) #156

Video is ‘unavailable’, Mark - but what 'doesn’t seem right"…?

xj6 85 Sov Europe (UK/NZ)


(Mark Lee (Pay Pal Patron)) #157

Really? I just tried it… hmm…

How about now?


(Mark Lee (Pay Pal Patron)) #158

The video explained or questioned rather, the order of the myriad of parts that hold the carrier on the fulcrum arm (thingy).

the order that it came off working from the center out

  1. spacer tube
  2. little shims
  3. bearing
  4. bigger shims
  5. felt inner seal / spacer
  6. spacer / felt seal cover(ish)

pressed in the carrier

  1. fulcrum bearing race
  2. thin ring about the
  3. felt seal retainer

My quandary in order.

  1. why the thin ring is between the bearing race and the felt seal retainer
  2. is the felt supposed to be facing outwards?
  3. Is oil / gear lube a better choice to lube the felt rather than grease, that just squishes out?
  4. In a nut shell what is the proper order? I’ve looked at the manual for the Series 1, 2, 3 XJ and the Series I is probably the best at illustrating, but it doesn’t say which way the felt goes. There is a cut away illustration that from what I can gather; I do have it in the right order, but I still don’t know about the felt. The video explains it better.

Thank you as usual Frank


(Aristides Balanos) #159


When I did mine I omitted the felt seals and put a lip seals instead, as suggested by Kirby in the Book.
I used a seal that had an outer lip as well and put them with the spring lip on the inside, to keep the grease in.
I think that this is a much better solution than the felt seal.

If you want to use the felt seals though, the felt retainer washer should be the other way around, at least this is how I understand it from the manual:


It makes sense, you don’t want the felt exposed to the elements collecting water and dirt.

As for the grease Zerks, It’s been a very long time since I did that but I think that Kirby’s Book has also a solution.



(Frank Andersen) #160

I think viewing the functions may be helpful, Mark…?

The central pieces are the bearings. Their outer races fits into the hub carrier - and the sleeves keeps the inner races from sliding inwards (distance pieces). And the shims adjusts the distance to ensure the inner and outer bearing races are running true with the correct preload(!)…

The smaller rings bears on the inner bearing races from the outside - pressing the inner races firmly against the inside sleeves/shims by the wishbone (when the nut is tightened) - locking the bearings in place.

The parts outside of that relates to the seal itself. The function of the seal is to ensure that the grease is caught and held by the felt - basically ensuring that the grease is applied to both the inside and the outside of the bearing.

As Aristides remarks; a lipped seal does that preventing water/dirt ingress from the outside - which, as he also says, is the task of the retainer washer when felt is used.

The main point of the ‘seal assembly’ is to prevent the felt from being squashed flat when the nut is tightened to the wishbone. Helped by the outer small shims, which applies nut (whishbone) torque to the inner races via the inner small rings. And the large spacers applies nut (wishbone) torque to the outer bearing races to keep them firmly fixed to the hub carrier - and enough on the seal retainers without undue squashing of the felt. There should be a clearance between the wishbone and the seal retainer…

It is of course essential that the assembly is symmetric - ensuring that the preload on the bearings are equal…

xj6 85 Sov urope (UK/NZ)

I don’t think the seals are ‘sided’, but if they are; the ‘soft’ side likely is closest to the bearings…?

Overall; the pint of the shims are to get the proper preload on the conical bearings. The preload is spec’ed to 0,000 - 0,002" - the shim pack to be adjusted accordingly.


(Mark Lee (Pay Pal Patron)) #161

alright, I’ve got the carrier assembled, received my “spacers” for what ever reason evidently I ordered a shit ton of the same sizes. SIX mind you of the .140 and SIX of the .136. I have now idea how I did that. Anyway, Just to make sure I understand this whole spacer .
I’m going to speak inches (because that’s what I’m use to - stupid American)
.032 - is my endplay
.004 is the median of acceptable tolerence (.002 - .006)
.028 is the actual endplay. .032 - .004 = .028

.150 “master spacer” the JD15 tool space enforcer.
.028 actual endplay
.122 is the shim / spacer size I need. Right?

.150 - .028 = .122

The one I pulled out was an .0137. I have a honing stone & a couple diamond honing stones, I guess I can try my hand at reducing the size a couple thou.

Am I missing something?

“Master Spacer” it reminds me of the first time my Dad and I went fishing - I think we all know where this is going…
After I got the hang of baiting the hook, My dad said nicely done! you are now the master baiter! At the time, I had no idea what that ment other than I could bait a hook.
I was proud of my new title. I told everyone I was the master baiter.

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