Jaguar XJ-S. Manual - part 100

 
 

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a wear pattern that looks like brinnelling but involves no impact.  Doesn’t really matter which, either way the bearings 
are ruined. 

Gran Turismo Jaguar (now defunct) offered a kit to replace the tapered roller bearing idea entirely with brass bushings. 
 Concours West (page 706) offers urethane bushings.  Either of these has the considerable benefit of being an order of 
magnitude easier to install, since there is no need for adjustment and fiddling with shims. 

However, whether or not going to bushings is actually an improvement is far from clear.  First, note that the entire point 
of renewing these bearings is to eliminate sources of slop in this joint, but you cannot adjust the slop out of bushings.  If 
the bushings don’t fit very snugly on the fulcrum shaft, the slop may get worse rather than better.  And even if the 
bushings are really snug, of course, any wear in those bushings would cause slop -- if you’re unlucky, more slop than 
would be caused by the wear rate of the OEM tapered roller bearings. 

There’s also the question of the quality of design and construction.  For example, the OEM assembly provides a stack 
of parts all the way through the assembly so that the fulcrum nuts can be torqued down tight without being concerned 
about distorting the fork on the end of the swingarm.  The same stack clearly won’t work since there are no longer any 
inner bearing races, so a well-designed bushing set would either provide a single sleeve to surround the fulcrum shaft 
and fit inside the bushings, or short sleeves for use with the OEM spacer tubes.  Steve Stewart says, “The solid bushes I 
put in the E-type were from Classic Jaguar in Texas (

www.classicjaguar.com

).  No sleeves at all.  The shafts fit straight 

through the bushings which are a nice push-in fit to the hub carrier and wishbones.”  Apparently you must be careful 
not to overtorque the fulcrum nuts so as not to distort the swingarm. 

Seals are apparently another issue.  Stewart continues:  “I don't believe that grease retention is as good as the roller 
bearing set up though as there are no seals used.  Also instruction to grease these every 3000 miles or so.” 

Actually, urethane or nylon bushings might be better than brass or bronze.  With plastic, it may be possible to assemble 
a really tight fit, and wear could be minimal if the load distribution is within the capacity of the plastic.  The plastic 
bushing might serve as a seal without requiring a separate seal; it might even be molded with a sealing lip.  It still 
should have a metal sleeve around the fulcrum shaft, though. 

All in all, it might be best to just maintain the OEM roller bearings properly and replace them periodically when they 
get worn.  They are not expensive, and replacement is pretty easy. 

 

REAR SWINGARM OUTER PIVOT - SEALS:  One common suggestion here is to reverse the felt seal and cup 
during assembly, but this is probably because the exploded diagram in the Parts Catalogue shows the felt seal and cup 
backwards and these people have just figured out the way it’s supposed to go. 

Even installed correctly, there is considerable history of rust, corrosion, and water damage with the outer pivot 
bearings.  Craig Sawyers says, “The truly awful felt seal ships water like you would expect; it simply acts like a wick.”   

In his column “Tech Talk” in Edition 82 of The Jaguar Magazine, Ron Moore recommends the seal C20178, its 
container C20179, and its retaining washer C20182 be omitted; if you printed this book in color, these parts are shown 
in magenta in Figure 22.  In their place, Moore recommends a “common oil seal PR6354” be installed instead -- 
backwards, with the flat side of the seal facing the bearing. 

More info on that seal:  PR6354 is a Repco part number, and it cross-references to a Federal-Mogul/National 471652 or 
a C-R 11124.  Timken also calls this seal a 471652.  The dimensions of this seal are 1.125 x 1.624 x 0.250.  Duncan 
Williamson says that Farrell Bearings Ltd stores in New Zealand provide a seal number TC12044 23560R.  Sawyers 
reports that Classic Spares (page 690) offers an “outer fulcrum bearing kit” that includes the bearings, an assortment of 
shims, and suitable oil seals instead of the OEM felt seals. 

Moore has a point about that backwards installation.  Seals are normally used to keep fluids in, but in this case they are 
used to keep fluids out.  The main lip within such a seal, which has a spring behind it, will hold fluids securely in the 
direction that would result in fluids coming out the flat side, but not as securely in the direction of fluid entering the flat 
side. 

 
 

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That wisdom notwithstanding, this author is going to recommend that you install the oil seal forwards, with the flat side 
on the outside.  Modern oil seals have two lips, the main one facing one way and a tiny one facing the other way, and 
either one of these seals -- facing either way -- is likely to seal far better than the felt seal assembly ever dreamed of 
sealing.  But perhaps more importantly, installing the oil seal flat side out would seem to provide better protection from 
physical damage; most of the delicate parts of the seal are enclosed behind the metal surround. 

Moore also suggests that the spring on the seal be removed and replaced with an O-ring BS024.  This is probably just 
because, with the backwards oil seal installation, the spring will eventually rust away since it is on the side of the seal 
exposed to the elements.  A suitable O-ring sold at Discount Auto Parts is made by O-Tite!, number 64024; it is 1-1/8” 
ID, 1-1/4” OD, 1/16” thick.  It even comes in packages of four.  Of course, you can omit the O-ring substitution and 
just leave the spring in there; it’ll probably last ten years, perhaps long enough you’ll need to be back in there to replace 
bearings anyway. 

If you install the oil seal flat side out, you should not make this O-ring substitution for the spring.  Rust won’t be a 
problem, since the spring will be inside the assembly and presumably well greased.  But the grease used may attack the 
nitrile of an O-ring. 

There is a spacer C20180 within the OEM assembly that holds the outer ring C20179 surrounding the felt seal away 
from the bearing.  A similar spacer is called for with the oil seal, but the oil seal is narrower than C20179 and therefore 
needs a wider spacer.  You have several options.  First and perhaps easiest, you can wrap a length of 0.064” steel wire 
(14 gauge) around a big socket to form a loop, and install it alongside C20180.  Since C20180 is about 0.095” wide, 
this will make the total about 0.160” wide, about right.  Figure 23 shows the oil seal and the wire loop spacer in red.  
Another option would be to cut a strip of sheet metal about 0.150” wide and wrap it around a big socket to make a loop 
and use that -- and throw C20180 away. 

Sawyers provides another option:  “Classic's verbal instructions for their kit of bits is to throw everything away except 
the seal track (C16628).  You just tap in the new grease seal until it is flush, or slightly recessed from the face of the 
hub.”  That’ll work if you’re careful and don’t tap it in too far. 

When you’re putting all this together, remember that water is sneaky.  With a good lip seal keeping the water from 
getting in between the seal and the seal track, that water might still sneak in there between the ID of the seal track and 
the fulcrum shaft itself.  Hence, it would probably be a good idea to put some sealant between the seal track and the 
fulcrum shaft, although it’s not clear how to get any to stay in there through the process of inserting the fulcrum shaft 
while driving the dummy shaft out. 

A better idea may be to apply a sealant such as Loctite 518 to both ends of the distance tube, both ends of each inner 
bearing race, both sides of each seal track and both sides of every shim.  This way, when the assembly is tightened up, 
all those joints will be sealed.  Water could conceivably get in along the fulcrum shaft, but it couldn’t get from there to 
the outside of the stack of parts along the shaft where the bearings and grease are.  A workable plan, but be careful not 
to slop too much sealant on any of those parts; you don’t want a lot of sealant squeezing out and getting into the 
bearings. 

While you’re being so careful to keep water out, note that Jaguar provided a nice little hole above the grease fitting to 
let in plenty of water.  See the section on greasing these bearings 389. 

 

REAR SWINGARM OUTER PIVOT - SHIMS:  As described below, there are two separate and distinct shimming 
procedures involved in rebuilding the rear swingarm outer pivot joint.  These two operations require two different shim 
designs; both need to fit on a 5/8” shaft and both require an assortment of thicknesses for adjustment, but the OD’s of 
the shims need to be different.  Craig Sawyers explains Jaguar’s shim numbering scheme:  “The parts book has two 
distinct types of C16626: 

C16626/1 

0.003" 

for fork centring 

C16626/2 

0.007" 

for fork centring 

C16626 0.003" 

for 

preload 

C16626/3 0.007" for 

preload 

 

 
 

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Preload shims: 

O/D 7/8", I/D 0.695 (11/16" clearance) 

Centring shims:  O/D 1-1/8", I/D 0.695 (11/16" clearance) 

“As you'll see, the preload ones are real skinny, with a wall of rather less than 3/32", as compared with the larger ones 
with 9/32".” 

“Centring” is gonna play hell with my spellchecker; why can’t the Brits learn to spell? 

The shims used for setting the bearing preload must have an OD smaller than 15/16” or they will interfere with the free 
movement of the bearing roller cage.  Shims with an OD smaller than 1-1/8” would work as fork spacing shims, but 
they will weaken the assembly somewhat; best to use the intended items. 

A comment from the author as engineer:  The guy at Jaguar who decided to give these two distinct and non-
interchangeable types of shims the same part number with different suffixes deserves a thump on the head. 

Note that you will need some preload shims to do this job.  The selection procedure involves assembling the bearings 
with too many preload shims, measuring the slop, and removing shims accordingly.  You can’t do that if you don’t 
have too many shims to begin with.  Just order a couple of each of the four shim part numbers while ordering the other 
parts you’ll need, and just put it down as the cost of a rebuild. 

Of course, you can find generic shims.  Grainger (page 708) offers an “arbor shim assortment”, stock number 3L739, 
for less than $10 that contains 19 different thickness 5/8” ID shims.  The OD is 1”, which really isn’t right for either 
preload shimming or fork shimming, but you could conceivably cut the OD down to use them as preload shims. 

You could also make shims, of course, by simply cutting them out of steel or brass shim stock. 

You need to know just how thick your shims are, so you know how many to remove to set the preload correctly.  It’s 
probably not a good idea to rely on Jaguar’s indication that its shims are 0.003” and 0.007”; Patrick MacNamara says, 
“My C16626s came from the dealer at .004".”  This author measured his brand new shims as 0.004” and 0.006”.  If you 
can, measure yours for yourself. 

 

REAR SWINGARM OUTER PIVOT - BEARING PRELOAD SHIMMING:  The first shimming procedure involved 
in the rear swingarm outer pivot assembly is to preload the tapered bearings properly.  When you tighten the nuts down 
on the fulcrum shaft, you’re gonna be jamming the cones of both tapered bearings down tight into the cups, so there is a 
“distance tube” -- or maybe two distance tubes end-to-end -- that space the cones apart.  Shims C16626 (.003”) and 
C16626/3 (.007”) need to be selected and installed to space the cones the precise amount necessary to provide the 
correct amount of preload; too many shims and the bearings will be rattly, too few and they will be jammed too tight.  
The shimming procedure is described in Section 65.15.07 of the ROM in steps 18 through 28, and also in the Haynes 
manual, Chapter 11, Section 22, in steps 10 through 16.  Basically, the idea is to put the assembly together with too 
many shims, measure the axial play, and then take it apart and remove shims equal to the play plus .002” -- yes, the 
assembly should be two thousandths tight when done. 

Both the ROM (step 22) and the Haynes (step 14) mention using an inner swingarm pivot thrust washer in this trial 
assembly; you measure the play between the washer and the edge of the hub carrier with feeler gauges.  Obviously, if 
you don’t have the inner swingarm pivot apart, that washer isn’t available -- and you aren’t going to want to take it 
apart just to borrow that washer for a minute.  All you need is a flat washer with a 5/8” hole in the middle and an OD of 
at least 1-3/4”.  Note, however, that it would be best to have a really good flat washer, as anything flimsy or with a 
rough or uneven surface may affect the feeler gauge reading -- and you’re looking to get the shim measurement right, 
not just close.  You might opt to file or machine on the face of that washer facing the hub carrier to get it as flat and true 
as possible.  Also: mark both the washer and the hub carrier housing so that you are always using the feeler gauges at 
the same spot. 

Of course, you could measure the end play using other methods.  You can set up a dial indicator, for example. 

The shims can be installed anywhere in the stack between the bearing cones -- at one end, the other end, or in the 
middle between the two distance tubes -- and it will accomplish the same thing.  The manuals describe putting them in 
the middle between the two distance tubes (steps 27 and 28 in the ROM, step 11 in the Haynes).  However, at some 

 
 

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point Jaguar figured out that manufacturing one long tube requires less machining than two short tubes.  The Parts 
Catalogue, ©1987, shows it as a single long tube C.16623/1.  In fact, every XJ-S owner who has reported says they 
found a single long tube rather than two short tubes.  So, just put the shims at one end or the other; it doesn’t matter 
which end. 

The cross-section diagrams in the ROM show a shim in the center between two short tubes.  If you have one long tube, 
don’t waste too much time trying to figure out what that drawing is trying to show you there. 

The ROM recommends tightening the trial assembly to 97-107 ft-lb, and the Haynes recommends 95 ft-lb.  Basically, 
this is final assembly torque.  Here, I will differ with the official recommendations and suggest you do not tighten the 
trial assembly that much; go to 40-50 ft-lb only. 

Here’s the reason: at trial assembly, you will be turning the two nuts against each other, and somewhere in the stack 
between them there must be slippage.  This slippage will probably occur at the shims.  In achieving full assembly 
torque, the thin shims may decide they’ve had enough and get ripped out of the stack forcefully by the shear loads.  
This isn’t a problem at final assembly, because the ends of the swingarm fork are involved; they positively prevent any 
twisting within the stack, and force the nuts to slip on the swingarm fork faces as they are tightened.  The shims won’t 
be harmed by pure compression. 

 

REAR SWINGARM OUTER PIVOT - SWINGARM FORK SHIMMING:  The second shimming job isn’t as critical 
as the bearing preload; the idea here is merely to make the bearing/seal stack nearly the same as the width of the fork on 
the swingarm so that as the nuts are tightened down the swingarm doesn’t get distorted.  Basically, insert shims 
C16626/1 (.003”) and C16626/2 (.007”) until the hub carrier fits snugly between the ends of the swingarm; put in as 
many shims as you can and still fit the hub carrier into the swingarm fork.  And put some of the shims at the front and 
some at the rear in order to position the hub carrier approximately centered in the fork. 

This shimming procedure is described in the ROM in Section 64.15.01 in step 10.  Or, I should say, isn’t described in 
step 10.  It just says to put the shims in.  The description in the Haynes, Chapter 11, Section 22, steps 18 and 19 is much 
better, brief as it is. 

Richard Dowling says, “When it was time to check for the large shims which ensure the assembly is a neat fit in the 
fulcrum fork, I first put all the bearings etc. into the hub and tried that in the fork.  It is just too clumsy and difficult to 
make sure the bearings are tight and at the same time check the end float for shim size.  Instead I went back to just 
putting the bearings, spacers and shims on the shaft and torquing it up with some spacers.  I then offered the shaft up to 
the fork and checked with feeler gauges.  Of course the shaft is not fully into the fork but it is easy to handle and 
measure.  On final assembly it is simple to see if you got that wrong, either the hub fit into the fork is too tight or there 
is obviously too much endplay.” 

Both the ROM and the Haynes seem to imply that these shims get installed between the hub carrier assembly and the 
swingarm fork, and the exploded diagram in the Parts Catalogue confirms it.  Don’t put them there!  Install these shims 
inside the oil seal track, between the oil seal track and the bearing. 

 

REAR SWINGARM OUTER PIVOT ASSEMBLY:  Confused?  Yeah, that’s understandable.  So, here is a brief 
summary of the assembly procedure using the oil seal in place of the felt seal.  Refer to Figure 23, which shows the 
assembly together at the right as well as the individual parts to the left -- indicating the order they should be installed.  
This procedure assumes that all parts are clean and ready for assembly, and whatever you decide to do with the grease 
relief vent has been done and any metal chips or whatever have been cleaned out.