The torque value from the manual is 75 ft-lbs, which matches torque table specs for a Grade 5 bolt installed dry. If you use sealer or thread locker I’d use a lower value. These should be 1/2"-13 (UNC).
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Perfect, thanks Rob.
Say, what are you all using for a drift to drive out the fulcrum bolt and not disrupt the bearings & seals? I thought I understood a 5/8" dowel would work or a 1/2" copper water pipe. Maybe the copper was of a metric size from across the pond? My 5/8" dowel measures 0.633" dia and the 1/2" copper pipe measures 0.627’ dia.
Also, driving out the fulcrum bolt is requiring more force than I anticipated. The small end of the yoke came out nicely. I am holding the yoke in my hand and there is no stress on the fulcrum bolt, but I’m hitting it pretty hard to remove it. Comments?
I don’t need to save the position of the seals et. al. at this time, but I thought it was timely to get my insertion rod/pipe figured out.
My torque table shows 57 lb-ft. for a lubricated 1/2 NC grade 5 bolt. Rob- use that torque if you put antisieze on the threads (recommended). Yes, the coefficient of friction makes that much difference in the amount of torque required to achieve a given preload in the fastener.
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A couple of ideas:
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Since the diff is/was not bolted to the cross member, it has probably shifted since the inner fulcrum shafts were installed. As the IRS appears to have been installed without those 4 bolts in place, I presume that the fulcrum shafts were all that was supporting the massive diff in the cage. It wouldn’t surprise me if things are “a little bent”
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With the tie plate removed (as in your photo), the front/rear faces of the cross member may have “sprung” outwards which will tend to jam the fulcrum shafts as they pass through the cross-member. You might want to try putting a clamp and/or spreader across the cross-member and experiment with drawing the edges together or pushing them apart to try to find a “sweet spot” where the shaft frees up somewhat.
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Hi Scott…dont be too heavy handed with the hammer on the fulcrum shafts…as David said the bottom plate removed probably dosnt help…try double nutting one end of the shaft with the other end nut removed and slowly wind it out…in tne UK 15mm copper plumbing pipe is ideal as a dummy shaft…Steve
Good tip remove the grease zerk (nipple) on bottom of the aluminium carrier…its very easy to snap them off…Steve
I used 5/8" rod stock from Lowe’s to drive out the fulcrum shafts, and plan to use it as a dummy shaft when I reinstall. The 5/8" rod worked well to remove one shaft, but I had trouble with the second - I think I had some old grease gumming up the works. I ended up using 1/2" rod stock and that worked for removing the second one.
@davidxk makes some good points about potential misalignment. Another thought I had is - if you eventually plan on removing the differential mounting brackets, might as well loosen the bolts now and maybe take some pressure off of the fulcrum shafts. That may help. I didn’t do this and only thought about it after-the-fact, but my fulcrum shafts weren’t too crazy to remove.
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Okay, I need to go back to my manual again. I appreciate the input.
David, thank you for the ideas. As a matter of fact, the bottom plate was not installed either when my aunt got the car back from the shop. I believe they made a roller out of it so they could push it on a trailer. 8 years later, I bought the car - 2003 - but it only rolled until this past summer. I put the bottom plate on in 2020. It fitted up pretty easily; I was expecting to have to use a clamp, but I did not.
Yep! And the fulcrum shafts: one had loose nuts and the other a missing nut. So yes, the fulcrum shafts took a hit. I will use a clamp as you suggest to see if I can find a sweet spot.
Thanks Steve. I’ll do as David suggests and use a clamp to find a sweet spot. I stopped because I just felt it was requiring too much of a hit to move it. Still, I did not beat it to death.
The UK’s 15mm pipe is somewhere between the USA’s 1/2" and 5/8" pipes. I think I’ll take a 5/8 wooden dowel and turn it down; I doubt that a bit of wobble in the diameter would be a hazard.
[quote=“ryaskovic, post:28, topic:416955”]
I used 5/8" rod stock
[/quote] Or as Rob suggest I find some 5/8 rod stock and find one a bit under 5/8".
Thanks for the zerk fitting tip. I’ll go remove mine now.
Also thanks Rob on loosening the mounting brackets, that might just free things up. I have to remove the differential just to assure myself what the shims are.
Thanks everyone! 
How high was the rear sitting …… because sometimes the springs can be too stiff and the result is the car sitting far too high at the rear…… don’t ask how I know this ! …. It’s something that can be corrected with the irs in the car but it is a pain … took 3 sets to get correct on one of my cars …. One original set, one from a well known supplier and a set from sngb with boge shockers …… just right!
you know Danny, I didn’t measure the rear height. It always looked right to me and I believe the springs are the originals. The front always looks a bit high, but there’s no bonnet on the car and no interior, so folks here tell me my front height is about right as is sits. I’ll have to compare the new Boge/Sachs I got from Welsh with the Konis (and 1 Girling) now that they’re out of the IRS.
Do you have a reference as to how you measured the three sets?
Removed the right side fulcrum bolt. This did not go as expected. It took considerable encouragement to get the bolt to come out. I loosened the one bolt I could on each side of the differential mounting brackets. Then I applied a clamp across the fulcrum bolt on the outside of the cage; and then a spreader. Regardless of what I did, I could no longer even turn the fulcrum bolt! Bummer! I got my engine lift and pulled up on the cage, tried spreading, tried squeezing the cage. No dice. I tried lifting just the pumpkin to take it’s weight off the cage and spreading/squeezing. No dice. Tied turning the fulcrum bolt in all weight-relieving arrangements; could not turn it with a 2 ft breaker bar. To the eye it is not apparent what is bent but something is I’m guessing. I got a bigger hammer and made the right side fulcrum bolt come out. It took quite an effort unfortunately. The bolt was under considerable tension until about half-way through the yoke and then it started to slide a bit easier. But not enough to take out without using the hammer.
With the bolt out, it looks like the yoke and cage are aligned. Today I’ll see if I can slide the new fulcrum bolt in as a check.
Notes: this is the side that hosted the damaged fulcrum bolt; damaged most likely by beating it in place. All the while, the yoke rotated freely on the fulcrum shaft…always. When I loosened the one bolt holding the fulcrum mount to the differential, that caused more stress on the bolt; I tightened that bolt back up but that did not relieve the stress.
On the pics below, observe the multiple parts that were on the rear part of the yoke arm vs. those that came off the front. Who would do such a thing!
I’m a bit bummed, but at least I’m on the necessary path to correct whatever is wrong. Also, there are no shims that I can see. I briefly looked at the manual about shimming the fulcrum; looks like a process I’ll have to go through.
Oh yeah, took my calipers to the hardware store and bought a 5/8" mild steel rod for the re-insertion time. I did not want to beat on it to get the wayward fulcrum bolt out, so I used a piece of rebar.
Hi Scot. …as your refurbing the whole thing i woukd deffinatly re shim the diff mount brackets to the diff…that way your sure that the fulcrum shaft fits perfect through the cage and diff mounts…its quite easy and fully detailed in the service manual…in one of your photos the hole in the cage for the fulcrum shaft looks quite large almost like there is a bush in it…is it just the photo?..Steve
Oak dowels, sanded down by hand, worked for me. I just wrapped them with coarse paper and twisted until they were snug. BTW, 1/2" copper tubing was too big for me too. There’s different wall thicknesses. I’ve got no idea what tubing I had but there was no way it was going in those holes.
Mine fought back the whole way too. You’d think at some point you could just pull them out but no dice.
Ah …. It beat me …… what surprised me was that the ones that came with the car were wrong …… but there again the car had been pulled apart and so maybe some bodge done …… the second set I bought on eBay advertised as for e type…… third set from sngb fine …… just goes to show you …… I know that there are threads on here that talk about springs and their ratings etc …. But I just looked at the heights …. My car sits at 590mm at the arch using the centreline of the hubs and full weight of spare in trunk and 3/4 fuel ( how often do you run with a full fuel load?)
It’s a good thing you are rebuilding this properly now …. You’d be really pissed off if the diff “fell out” ….it would be very disappointing on a newly recommissioned car
I’d say “fell out” would be putting it mildly. I’d think it would have wrenched and twisted itself right out of the cage if any sort of power had been applied. 
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I was being polite clive
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