Overdrive switch location

[Chris Ob1]

I’m 3 weeks into the ownership of my 1st Stag, a TV8 with manual A-type overdrive. There doesn’t seem to be an isolator switch in the overdrive circuit as I can get overdrive in all gears including (worryingly) reverse. Looking at the repair operations manual it would seem the switch should locate below the gear-lever on a bracket of some description. This doesn’t seem to exist on my car so am I correct in thinking this is where the switch should be?
Any thoughts gratefully received.

[trunt]

ISTR On the Stag gearbox it should be on the extension cover just in front of the gear lever (same as 74-on TR6). **EDIT-

See this from buckeye triumph website..

https://static1.squarespace.com/static/5c6dec53b10f25d4edf0b3f7/t/5d019590f90de40001aacd9b/1560384913595/Gearbox+Cover.pdf

[trunt]

I looked at the Rom and saw the bracket you mentioned.. not a clue! There is a similar bracket on the J type but never seen it associated with the inhibit switch.

Ha! found a reference in a post.. "very early stags had a bracket" Post#6

https://www.socforum.com/forum/forum/stag-owners-club/soc-forum/23254-overdrive-install-details

[NeilR]

Only ever seen an O/D inhibitor switch in the extension, on both A & J types, in line with 3rd & 4th selector rod.
Doesn't mean they were never fitted on a bracket though.

[richardthestag]

the switch as stated above is located on the tip of the selector extension. remove the gearstick gaiter and you can just about see the bracket and switch on the handbrake side of the gearstick hole.

There should be 2 wires going to it and it sits in series with the solenoid, I say this because it is entirely possible that an issue occurred and a new wire was run straight to the solenoid, avoiding the inhibit switch.

Like with most 1970s switches, most are very simple in operation and rarely need much more that a clean up with contact cleaner

[Chris Ob1]

Thank you all for your help. Next question - any ideas where I can get said bracket? Searched Rimmers and J Paddocks sites with no luck. Alternatively does anyone have photos of an example I could use to fabricate the bracket? May then be able to install it without having to drop the gearbox!

[richardthestag]

Hi Chris, there is a chap called Tony White who has a huge stock of triumph used parts. He has a thread here

https://www.socforum.com/forum/forum/stag-owners-club/for-sale-wanted-swap/783547-after-25-years-of-hoarding

Post a request and he should get back to you.

[trunt]

Thank you all for your help. Next question - any ideas where I can get said bracket? Searched Rimmers and J Paddocks sites with no luck. Alternatively does anyone have photos of an example I could use to fabricate the bracket? May then be able to install it without having to drop the gearbox!

Are you sure it needs the bracket? That’s a very rare and very very early version of the gearbox? Plus I can’t see how it could work on both 3 and 4 gear? What year is your car?

whatever you do it will probably involve dropping the tail of the gearbox at a minimum

If you don’t have a hole in the normal position there is the possibility of adding the switch to any top cover as detailed in the link below… this is how mine is set up as I did not have a correct top cover. Alternatively any TR overdrive gearbox top cover can be used..

https://static1.squarespace.com/static/5c6dec53b10f25d4edf0b3f7/t/5d0195838ed02e0001596bc0/1560384900296/OD+Isolator+Switches.pdf

[Chris Ob1]

Thanks Richard, found a number for him and left message

[Chris Ob1]

It’s a 1971 car. I may end up getting the gearbox taken out anyway as finding 3rd gear can be a bit hit and miss although having driven a TR6 they may all be a bit like that. It looks as if it would work as the 3rd 4th selector shaft extends beyond the rear of the housing and seems to have a notch in it which would operate the isolator switch - arrowed in the pic below
IMG_20230907_094839_resized_20230907_094906902.jpg

[DJT]

Just to confuse matters, this was the gearbox on my first Stag, built Nov 1971, showing the reverse light switch on the top of the extension. The OD inhibitor switch was at the base of the gear-lever on a bracket, but unfortunately I don't have a picture of that.
DSC00022.jpg

[Chris Ob1]

Thanks Dave, spoken to Tony White and he’s looking to see if he has such a bracket. If not then overdrive fuse out to avoid accidents until I can get the box taken out and a switch put in the cover.

[NeilR]

It is possible to remove the cover without taking the box out, just needs lowering which needs exhaust downpipes & gearbox mount removal.
I've done that twice (on different cars) to replace selector shaft seals.

[richardthestag]

Here is an extract from an early ROM that only has the A-Type over drive

a-type.jpg

The bracket I have seen ( on a 1971 Stag with a-type overdrive) had a bracket the wrapped 1/2 ish of the diameter of the gearstick hole, one fixing was the one shown holding the vertical bracket. The inhibit switch iirc was mounted level with the gearstick hole on the extension and a little higher up than the item shown above. Maybe it wasnt a stag ?

Here is how buckeye adapted an early gearstick extension to accommodate the multiple switches.

https://www.buckeyetriumphs.org/gearbox

The switch I worked with was operated in line with the tail end of the 3 / 4 gear selector rod.

I cannot be the only person who has seen this. Am going to search triumph 2000 and TR5/6 to see if I can find proof that this exists

[Chris Ob1]

Thanks yet again Richard. The diagram is the one I’ve seen in the repair ops manual. Not heard anything back from Tony White about whether he has a bracket available. Might try fabricating one.