KYB rear shocks for 1977 X1/9

[MSiege]

Good point, thanks

 

[JimD]

Looking at @MikeHynes pictures you can see the silver cone is keyed to the shaft. You can grab the cone with a vice grips and tighten the main nut. Note that there are two small notches in the top edge of the cone, there is a factory tool that fits those notches to hold the cone during tightening. I have never found the factory tool. A vice grip works fine, just get a good pinch on the edge of the cone.

I have never tried to torque them to a specific value, I just tighten them up and then check them for a few drives.

 

[Ics19]

and the large washer

Large washer? There is no need for this in the correct rear setup of the 'late' struts - see @MikeHynes excellent explanation and pictures above. You can only use the 'late' rear perch units with the rear KYB's due to the lack of machining at the top. I'm guessing you have an early perch unit + washer + alloy cone, or indeed no cone if the washers are deforming? Best to take a picture of the disassembled pieces you are using.

Regarding tightening up, then see this picture by @Cratecruncher if you clean up the notches in the top cones, then a C-spanner can be used. Although this is a front strut, see how much clearance there is between perch top and mount - this is what you should have at the rears too.

There are torque settings for the top rod nut and pillar bolts, which curiously are the same:

As @JimD mentioned, there is a proper tool, but I must admit I've only seen it listed for Scorpion/Montecarlo, but a C-spanner looks cheaper and easier:

 

[ng_randolph]

I am revitalizing this old post because I am putting rear KYBs back together on my '77. I'm following everything discussed and pictured above and I seem to have a mishmash of parts - old upper assembly, but new mounting brackets. There is very little threaded rod coming through at the top end of the upper mount. I have replaced the upper mount with those new, much more robust rubber bushings and the large washer because the old ones were literally deformed to a concave shape by wear and tear, and whatever torque value was used in mounting. This has reduced the length of the shaft available for the upper nut.

My questions - Is it ok if the nut and shaft are basically flush when tightened down? What's the torque value for that top nut and should it have a final tightening before the assembly and upper mount is bolted in or after? I can leave the spring compressor on while its being mounted, tighten the shaft and then remove the compressor. It's hard to hold the assembly to tighten the nut without using the mount for leverage. Without enough rod protruding, there's no way to use a wrench on the machined part of the rod at the top, against the tightening of the nut.

Thoughts on this would be much appreciated, thanks.

The manual calls out "Not, strut assembly top mounting, M12 x 1.25: 59 Nm (43 Ft-lb)"

When torquing this nut, you are compressing the rubber in the top strut mount, so you'll be turning that wrench quite a bit to get to the torque spec. When properly torqued, mine shows about 10 mm of the threaded strut shaft above the nut. I have KYB struts all around, and I have the Mark Playa / Chris Obert designed / supplied upper strut mounts.

 

[MSiege]

Here’s what I took off the car. It looks like a combination of new and old. Do I understand that I can eliminate the three pieces that were between the upper perch and the upper mount? The large washer, the plastic bushing/spacer piece and the rubber gasket? That leaves the upper mount sitting directly on the perch and centered by the cone from above.

 

[Ics19]

Here’s what I took off the car. It looks like a combination of new and old. Do I understand that I can eliminate the three pieces that were between the upper perch and the upper mount? The large washer, the plastic bushing/spacer piece and the rubber gasket? That leaves the upper mount sitting directly on the perch and centered by the cone from above.

ahhh - no, you're missing the vital late type perch unit that replaces all you have and allows the KYB to be used properly. What you have there is the early perch that operates in the same way as a front strut and needs the same pivot components to give the correct height i.e. the large washer, thrust bush and rubber seal - the PO "conversion" has simply lost the alloy cone (shown below) as the rod can't fully fit in place - it's unsafe at best:

This explains why your washer was being deformed - the pivot parts are not suitable for the KYB struts which are only available with the late rod top style. You need to get the correct late type perch units and just use as is - have a look on MWB or place a post in FSW

 

[MSiege]

Alright, I finally have it now! Thanks for everyone’s patience. PO installed KYBs but somehow decided not to buy updated perches and tried to seat them incorrectly on the old perches. That explains why the large washer tried to become a lower cone. I also found one upper mount had only two studs - a real mess all around!

All I wanted to do was replace the uppers so I’d know it was stable back there. Ordering the correct perches now. I will put it back together and get back to other projects.

 

[MSiege]

I now have the correct assembly. Thanks again for your patience. I've done a lot on little cars but never strut suspension work like this.
So, last question (I think) ... how do I align/rotate the strut assembly so that the three mounting bolts on the top mount and the two bolts on the lower mount meet the three upper body holes and the two lower bolt holes? Can the piston nut be loose enough to allow the upper mount to rotate into place and then after the three bolts are tightened, it gets tightened for the last time? Or is there an alignment mark or standard I should use?

 

[kmead]

I now have the correct assembly. Thanks again for your patience. I've done a lot on little cars but never strut suspension work like this.
So, last question (I think) ... how do I align/rotate the strut assembly so that the three mounting bolts on the top mount and the two bolts on the lower mount meet the three upper body holes and the two lower bolt holes? Can the piston nut be loose enough to allow the upper mount to rotate into place and then after the three bolts are tightened, it gets tightened for the last time? Or is there an alignment mark or standard I should use?

You can rotate the upper three bolt mount relative to the top of the shaft.

 

[Steve Thomas]

You can rotate the upper three bolt mount relative to the top of the shaft

without tools or dissassembly