Jag IRS hub outer fulcrum shaft question
 

I'm trying to prep some parts for the ERA FIA car that I have on order and I started working on the Jag IRS hubs this weekend. Setting end float on the wheel bearings is easy enough but I'm having trouble with the outer fulcrum shaft preload.

I bought rebuild kits from xks.com, the kits came with bearings, shims, seals and distance tubes. Oddly enough, the kit is for a series II with the one peice distance tubes and they sent 2 distance tubes (not two short tubes for a two peice set up but two long distance tubes that should be in the series II). Anyway, my plan was to put all of the inner shims (the ones between the bearing and distance tube) in there, measure end float and subtract what I need to set preload, seemed pretty basic.

I put new bearing tracks in the carrier, a nut on the shaft, spacer on the shaft, bearing on the shaft, distance tube on the shaft, shaft into the carrier, all of the inner shims that came with the rebuild kit , another bearing, spacer, a spacer to take up the extra space on the shaft and torqued to spec. Even with all of the spacers I still ended up loading the bearings, no end float what so ever. I took the bearing back out and added all of the old spacers, retorqued and the same thing happened. I'm not able to achieve any end float.

I was wondering if anyone here has ever experianced this issue? Is it possible that the new distance tube is slightly shorter than the factory one? It is possible that I'm just doing something stupid, but I figured I'd check here if anyone experianced in the Jag IRS hubs has any advice.

I rebuilt mine on ERA 178. No issues. It went together per the manual with no surprises.

Your problem description sounds about right. Did you try to assemble with the old distance tube? I would think the float would be really close if you used the old distance tube and shims.

John

I am going to try to rebuild one with the old tube, if I can find it. I'm sure I put it in a box somewhere. In an act of foolishness I ended up thinking I wouldn't need them seeing the rebuild kit from xks.com came with new ones. I actually took one of the old tubes to the band saw to make myself a spacer to take up the empty section of rod while setting preload, and I really wish I wouldn't have.

I pulled the outer fulcrums apart today and inspected the tubes and they are actually deformed on one end now (the end that I stacked the shims on. I'm guessing the metal used for the repo peices is too soft. This has also seemed to have taken a toll on the shims. If I ever end up doing this again I'm definatly just reusing the tubes. I guess my options now are find an old one and measure it to have some harder peices made. Or I'll talk to ERA tomorrow and see where they get theirs if they replace them.

ERA will be a good source. When I did mine, they were cheaper for Jag shims and knew what I needed.

I am impressed that you tackled the Jag rear. Most people are scared to do them.

John

Bearwolf, the last time a thread like this came up the discussion turned to the price difference between the traditional Jag rear and the ERA outboard braked rear. At that time, the price had gotten down so low that it seemed like it was almost a "gimmee." ERA takes Jag rears in on trades up, so when you chat with them ask them "if I send you my rear in trade, what's the out of pocket cost to move up to the ERA rear?" Doing anything on the ERA rear is easier than it is on the Jag rear.

By the way, I remembered reading this guy's Jag rebuild blog and his page on setting the float for the outer fulcrum bearings. He writes that If you are installing new bearings, you should install more shims than necessary to get a large enough float to measure. Usually 0.010" - 0.020". See Step 20 It took me a while to find it (and I didn't want to quote it from memory). Here you go: https://relicrecyclery.com/Jaguar/page30/63XKE_30j.htm

That's a pretty good blog. I was doing it right all along, I think the aftermarket distance tubes were just too soft. I talked to ERA and they are sending me new distance tubes and shims. I can't say enough good about ERA and I don't even have the car yet. I also talked to xks.com, who I got the first set of parts from. We will see how it goes with them.

Just curious, but is there a reason you went with the original design instead of this?

Team CJ system bronze

I am of the understanding that the original style bearings have less of a tendency for binding than bushings and will travel more freely while cornering, making for a more predictable suspension. However I've never dealt with this Jag stuff before so I could be wrong. The bushings look a little easier but the bearings aren't all that hard (if I receive quality parts).