Author Topic: TCS Reverse Gear Detente - This worked for me  (Read 485 times)

0 Members and 1 Guest are viewing this topic.

Offline HoraceM22

  • Newbie
  • *
  • Joined: Mar 2024
  • Location: Daventry, Northants
  • Posts: 35
TCS Reverse Gear Detente - This worked for me
« on: Friday,August 16, 2024, 08:26:41 AM »
After a few drives in my newly acquired UK spec ’74 TCS, I found I just couldn’t cope with the mental or physical strain of second and reverse gears getting too intimate. Searching around here for possible solutions didn’t fill me with hope so I decided to investigate a way of only being able to choose the gear I wanted, not the ones offered by the gear lever!
After removing the gear knob and the “transmission tunnel” cover I checked to see what I was dealing with and what the angular separation was between second and reverse gears. Noting this, I then thought of how I might stop this clashing. I decided to make a solid “stop” block at the first/second gear plane that would then need to be altered to allow the gear lever to go through its détente into the reverse plane.
I cut some cardboard into a rough “L” shape (see the photos) and tried it for size, then did the same in wood and finally in about ½”. thick aluminium (I didn’t have any aluminum…..). Obviously I was careful positioning and drilling the holes to ensure I didn’t hit anything vital in the gear lever location and had to file a clearance slot to miss one of the bolts. (pic Gear Lever 3).
I found a 20mm dia. piece of ally tube with a ½” hole in that fitted nicely around the gear lever. This allowed me to position the L shaped piece with the lever exactly in the 1st/2nd plane. I had already filed the top 16deg. angle of the “L” piece.
Having small hands, I could get through the oval opening and under the gear lever, then loosely bolt the plate in position to check all was OK. I then made the proper tapered stop bar in stainless (that’s all I had that was of the right’ish size, and it doesn't need to be tapered I realised later!). After some small adjustments it all got bolted up tight, not easy to get at but possible. Keep a magnet on a stick handy to pick up your spanners from the tunnel floor!
Having also made the big double tapered shiny (as it’s visible) stainless “washer” that would be positioned near the top of the gear leaver to be used to lift the lower tapered part up, it was just a matter or drilling through both of them and connecting them together with a 3mm dia piece of stainless bar, making the holes a bit larger and using glassfibre resin as adhesive, filing off any excess.
I did have to make a small cut in the rubber gaiter to allow these two bits to rise, and more importantly, fall freely. I made these two parts out of stainless instead of ally to be heavy enough to fall back into place coming out of reverse.
This all worked to my satisfaction and might work for anyone else who feels the need to try and improve their gearchanging experience. The enclosed drawings are the sizes that worked for me, but yours might be different, but this could give you some idea of my design.
ATB
H.
HoraceM22

Offline HoraceM22

  • Newbie
  • *
  • Joined: Mar 2024
  • Location: Daventry, Northants
  • Posts: 35
Re: TCS Reverse Gear Detente - This worked for me
« Reply #1 on: Friday,August 16, 2024, 08:30:41 AM »
There should have been loads of pictures!!!
HoraceM22

Offline HoraceM22

  • Newbie
  • *
  • Joined: Mar 2024
  • Location: Daventry, Northants
  • Posts: 35
Re: TCS Reverse Gear Detente - This worked for me
« Reply #2 on: Friday,August 16, 2024, 08:50:17 AM »
It will probably help if the photo's are seen in order. Don't know why some didn't show as photo's
HoraceM22

Offline EuropaTC

  • Super Member
  • *******
  • Joined: Jun 2012
  • Location: Lincolnshire, UK
  • Posts: 3,116
    • LotusLand
Re: TCS Reverse Gear Detente - This worked for me
« Reply #3 on: Friday,August 16, 2024, 08:57:54 AM »
I think it might be because a couple are PDF's and so being given as downloads where a .JPG file is obviously an image and displayed when you click ?

Offline BDA

  • Super Member
  • *******
  • Joined: Jul 2012
  • Location: North Carolina
  • Posts: 9,888
Re: TCS Reverse Gear Detente - This worked for me
« Reply #4 on: Friday,August 16, 2024, 09:08:23 AM »
Nicely done HoraceM22!   :welder:


Offline HoraceM22

  • Newbie
  • *
  • Joined: Mar 2024
  • Location: Daventry, Northants
  • Posts: 35
Re: TCS Reverse Gear Detente - This worked for me
« Reply #5 on: Friday,August 16, 2024, 12:08:59 PM »
Forgot this photo. It's of the lifting set-up, but of the first try, and look crap, hence the better looking stainless top "washer", but you get the idea.
HoraceM22

Offline Dilkris

  • Hero Member
  • *****
  • Joined: Oct 2017
  • Location: Shrewsbury (UK)
  • Posts: 613
Re: TCS Reverse Gear Detente - This worked for me
« Reply #6 on: Saturday,August 17, 2024, 12:04:59 AM »
I was fascinated, impressed and at the same time somewhat confused with this - were you running the external cam plate and spring loaded ball for the 5th and reverse gears on the rear of the 365 box or had it been removed?
« Last Edit: Saturday,August 17, 2024, 04:01:54 AM by Dilkris »

Offline S2Zetec54

  • Full Member
  • ***
  • Joined: Feb 2021
  • Location: UK
  • Posts: 225
Re: TCS Reverse Gear Detente - This worked for me
« Reply #7 on: Saturday,August 17, 2024, 01:36:13 AM »
Good idea 👍

Offline jbcollier

  • Super Member
  • *******
  • Joined: Nov 2013
  • Location: Edmonton, Alberta, Canada
  • Posts: 5,935
Re: TCS Reverse Gear Detente - This worked for me
« Reply #8 on: Saturday,August 17, 2024, 10:14:17 AM »
Nice, did the same for mine as well.

https://www.lotuseuropa.org/LotusForum/index.php?topic=1692.msg15341#msg15341

Makes shifting a breeze.

Offline HoraceM22

  • Newbie
  • *
  • Joined: Mar 2024
  • Location: Daventry, Northants
  • Posts: 35
Re: TCS Reverse Gear Detente - This worked for me
« Reply #9 on: Tuesday,August 20, 2024, 12:03:06 AM »
Dilkris, As I had just bought the car and have subsequently found out about the vast amount of money that has been spent on it in 2016, I assumed, and still do, that the gearbox is totally as standard. In the invoice detailing the big spend by the owner two before me it just says "send gearbox off for specialist repair"
After talking to several Europa specialists, asking about improving the gearchange on these, ( one telling me that mine was one of the best he'd driven!!! ) one of them told me of a couple of guys who had spent a load of time fiddling around with the ball bearing linkage/setup at the back which often didn't work and occasionally was made worse. As I have to work on my car alone ( my wife will come a press the brake pedal but that's about it), I decided that, as I couldn't see what goes on at the back whilst gearchanging at the front, not to try that route and make a positive stop block in the 1st/2nd plane which definitely won't allow it to get reverse gear.
It definitely give me peace of mind, but I still find coming from 5th to 4th occasionally a bit of a challenge , not being able to find a gear where 4th should be, so going to 3rd instead. I assume it's just the synchro design not being good enough.
HoraceM22

Offline Dilkris

  • Hero Member
  • *****
  • Joined: Oct 2017
  • Location: Shrewsbury (UK)
  • Posts: 613
Re: TCS Reverse Gear Detente - This worked for me
« Reply #10 on: Tuesday,August 20, 2024, 12:29:17 AM »
HoraceM22 - I understand.
Gearchange on the 365 box is a subject discussed at great length on this forum - with a variety of suggested solutions. (Some even maintain removing the external lotus add on "Heath Robinson" cam plate affair and replacing the original ball and spring within the gearbox - which to my knowledge no one really knows why it was removed by Lotus in the first place....)   
Everyone seems to agree though that changing gear on a 365 is an "art" to perfect and practice makes perfect.
Sounds like you're doing good.   

Offline 4129R

  • Super Member
  • *******
  • Joined: May 2014
  • Location: Norfolk, United Kingdom, not far from Hethel the home of Lotus.
  • Posts: 2,707
Re: TCS Reverse Gear Detente - This worked for me
« Reply #11 on: Tuesday,August 20, 2024, 12:50:16 AM »
Gearchange on the 365 box is a subject discussed at great length on this forum - with a variety of suggested solutions.
Everyone seems to agree though that changing gear on a 365 is an "art" to perfect and practice makes perfect.

To get into 5th, I have to think and make the change deliberate and precise. 1st through to 4th is quite easy, but 5th can be a challenge every time.

My new reverse and 5th detent housing, ball, and spring, arrive today from SJS, so hopefully I can get 5th on the current car I am working on.

Offline 4129R

  • Super Member
  • *******
  • Joined: May 2014
  • Location: Norfolk, United Kingdom, not far from Hethel the home of Lotus.
  • Posts: 2,707
Re: TCS Reverse Gear Detente - This worked for me
« Reply #12 on: Tuesday,August 20, 2024, 03:24:45 AM »
I have just spent 2 hours fitting the ally detent housing to the steel gearbox rear mounting plate to get R and 5 to work.

1st problem, the holes in the gearbox mounting plate were too big for the 5mm bolts needed to secure the housing to the mounting plate. Therefore the housing moved around on the mounting plate as soon as I started moving the gear selector rod.

So I aligned the housing exactly, and it has to be exact both in angle and distance from the cam, and drilled 2 x 4mm holes through from the back plate into the ally housing and put 2 short roll pins in to precisely locate the housing to the back plate with zero movement.

2nd problem, although the housing was rigid and properly aligned and distanced, it would work for R but not for 5.

I carefully filed the cam horn a very little, and the ball then retracted properly. It may have been corrosion on the cam horn but the difference between failure and success is minute.

Next problem, when you drop the back of the gearbox down to take the mounting plate off, the hose always comes off the water pump. So next, careful jacking up of the rear of the gearbox while trying to get the hose back on the pump.