Lotus Europa Forums > Technical Articles and DIY tools and tips
TCS Shift Linkage Center Bushing - Polyurethane
3929R:
I installed the bronze oilite bushings on the linkage at the shift lever and put the linkage back into the car. With new bushings at the shift lever and center pivot I was able to determine that one of the roll pins at the center pivot was worn and allowing movement. I put in a new roll pin and the whole linkage is as tight as it ever was and I can now find the gears! (The linkage at the transmission is tight so I am saving any mods to that for another day.) The car is much more enjoyable to drive. I can shift through and know what is where.... except for 5th.
I can not shift into 5th. But it was there a month ago and though SLOPPY, I could pop it into 5th without too much agony or searching! Now I can not find it at all. I believe that on my TCS the reverse and 5th detent cam ramp profile has been modified such that it should be (and was?) easier to shift into 5th (see picture below). I need to double check but I see no evidence that the detent mechanism has slipped or come out of adjustment. Thus I am hesitant to mess with it.
I am wondering if I changed the effective length of the shift linkage when I drilled a new hole and added a new split pin to the universal joint at the center pivot (part #FB9)? It does feel as though I can push the shift lever too far left for 1st gear, though I'm not sure if this is too far left for reverse. But how much could have turned the loose end? Maybe 1/8 of a turn? Is that enough to lose 5th?
Any thoughts????? Is there something else I should be looking at?
pboedker:
Hi Mark,
I've come into this discussion a little late due to summer vacation, but this all looks good. :)
Your FB13 bushing, I believe, will work well and probably maintain its shape better and longer than the standard rubber bushing. Should be interesting if you will notice any vibrations from the stiffer material, probably not. On mine (rubber bushing) it had a tendency to slide through the pivot sleeve so that the pivot sleeve would grind on the bracket. I solved this by drilling for a set screw into the side of the pivot sleeve. So, just check if your new bushing stays put.
BTW (should I answer this post, the thread on our good old Europalist or both, sigh!) the alu block at your shift lever is precisely as mine. And it should be with only 25 between the VIN numbers. But I think they all are alike from TC (late S2?) and onwards, it's just the paperwork that needs some updating.
About your missing 5th gear...
Provided that you haven't touched the detent cam and ball, the problem must be in the middle joint. I don't think the length change will be very important, but maybe you've turned it a little bit so that the shift lever itself is not able to move far enough to the right. The lever goes through the ball joint and there's only so much movement possible left/right in the ball joint. Or the bottom of the lever could be restricted by something inside the tunnel.
The manual says to adjust a new linkage BOTH at the middle and then at the detent cam. Since the detent cam follows the internals of the gearbox, your's must still be good and it's just a matter of rotating the front part of the linkage sufficiently.
I had a similar problem because I broke the forward part of the middle universal joint on removal, so it had some threads left but not enough to put a pin through it. >:( But I made quick and dirty fix using a lock nut instead and it hasn't loosened in 9 years now. The nut had to be grinded flat so as not to interfere with the ball joint and the fore/aft motion, but it really gave an infinite possibility for the angle adjustment. I'm not saying it's good and stable solution, just that it was a desperate try that ultimately turned out to solve the problem OK.
3929R:
Thanks for the reply Peter. I really appreciate the insight. I am happy enough to just have you reply here. I also posted my question to the Europalist just to cast a wider net, and possibly get more feedback. So far no replies on the Europalist.
I've got some time today and I'm going to tinker with the middle joint. What you said about the length not being very important but the rotational adjustment being off enough to not allow me to reach 5th makes sense. I have to figure out how to adjust it back without drilling so many holes for pins as to trash it. Currently it has 2.5 pins on the front threads and 1 on the back. The .5 being some odd solid pin on the collar(further toward the front of car than the original pin) that does no extend all the way through. Removing this may be difficult as its hole does not extend through. I may convert to a lock nut, such as you and others have done.
I did notice some minor vibration on the gear shift while driving but not enough to be any sort of annoyance. I will keep an eye on the bushing in the pivot sleeve and if it slides, use your set screw idea.
3929R:
1 step forward. 2 steps back.
Part of the reason that I couldn't find 5th is because one of the bolts that anchors the middle pivot to the bell housing was missing :WTF: . I didn't take it out but I should have noticed it was missing. I replaced the bolt (it is the same diameter and pitch but longer than the bolt above it in the bell housing) and could shift into 5th in the garage. Took the car out on the road and shifted 1 to 4th, then a grind and bam :blowup: the shoulder bolt on the bottom of the shift lever sheared off causing the shift linkage to fall uselessly into the frame tunnel. I pulled over, reached into the frame tunnel, and managed to get into 1st gear so I could crawl home.
I don't see how the attempted shift into 5th could have sheared the bolt unless it was already damage and just waiting for an excuse to fail. I think it must have been damaged due to over tightening when the bushing was missing.
Anyone have a spare shoulder bolt for the bottom of the shift lever on a TCS they are willing to part with? RD sells them but I think they are not the same dimensions as stock.
3929R:
--- Quote from: pboedker on Friday,August 10, 2012, 03:34:03 AM ---....using a lock nut instead and it hasn't loosened in 9 years now. The nut had to be grinded flat so as not to interfere with the ball joint and the fore/aft motion, but it really gave an infinite possibility for the angle adjustment. I'm not saying it's good and stable solution, just that it was a desperate try that ultimately turned out to solve the problem OK.
--- End quote ---
Any idea what size nut you used?
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version