Lotus Elan and Lotus Elan Plus 2 Forums

I rebuilt my rear suspension on my 69 SE with adjustable ride height coil overs and CV axles. I decided on the TTR fast road rear struts which are Konis Yellows with a droop limiter. I noticed that the strut body when inserted into the tube, sits proud of the top of the tube for about 1/8" on both sides. When you tighten the flange caps, they also hit home about 1/8" too high. I spoke to Stuart at TTR about this and he tells me that this is normal. So the question I have is, since these tubes have to filled with oil, has anyone experienced leaks down the road. I intend to use teflon tape and maybe a fat O ring to close the gap and to keep dirt from accumulating on the exposed threads. But would like the comments of those who have installed these to see if this is an issue and if I should be taking any additional precautions. Thanks Allan

Allan,
I believe the situation you have is normal. Keep in mind that the strut insert needs to be forced downward into engagement with the outer tube at the bottom of the assembly. This can't happen if the nut at the top runs all the way home to the top of the outer tube. When the insert is located at both the top and bottom of the outer tube then bending moments are reacted by the full length of the strut insert and the outer tube. I have replaced strut inserts a couple of times in my +2 over the decades and the insert and nut always stand a bit proud of the outer tube and I have not had a problem with the oil between the insert and the outer tube leaking. From what I see in your photos both the insert and nut stand a bit more proud than I have seen in the past. How much thread on the nut is engaged in the outer tube? Your idea of using a bit of teflon pipe thread tape certainly would not hurt, the fat o-ring is also a good idea.

Mine looked just the same when I carried out a TTR rear strut upgrade.

Regards

Peter

Thanks for all the knowledgable replies. While I was not refuting TTR's experienced advice, I just get uncomfortable when things do not fit the way I expect them to, and my mind spins with potential problems that may arise. So, thank you for the hand holding lol.

The flange nut seats on about 75% of the threads. While this is a machine thread, rather than a pipe thread, it does get tighter the further it is threaded into the tube. I assume this is due to the "peen" that was done at the factory to lock the flange nut to the tube, as when you turn out the original nut, it spreads the top threads not to mention wrecks the flange nut threads as well. My attempts to straighten out these internal threads with a die most likely widened these threads further. But the new nut threads on smoothly albeit a little loose until it hits home. But since I didn't see any type of seal, I was worried that the oil would leak out, either from the threaded portion of the nut, or through the shaft and nut. I'll use the Teflon tape and o ring, but do you think some added silicon around the shaft / nut is necessary as well? Thanks again Allan

gearbox wrote:The flange nut seats on about 75% of the threads. While this is a machine thread, rather than a pipe thread, it does get tighter the further it is threaded into the tube. I assume this is due to the "peen" that was done at the factory to lock the flange nut to the tube, as when you turn out the original nut, it spreads the top threads not to mention wrecks the flange nut threads as well. My attempts to straighten out these internal threads with a die most likely widened these threads further.

It's a good idea to drill out the dot punch before removing the cap nut then you don't chew up the threads in the tube - at least not quite so much

Hi Allan

Mine was like yours, the flange nut stood a couple of mm above the strut-tube. I put the nut in the lathe and turned the inside diameter of the nut down a bit further, so the nut could be screwed almost fully down in the strut-tube. It was not that I was afraid that the oil would leak out, but I was afraid that the nut might come undone.