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Is a Triumph overdrive tranny all that?

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glemon said:
OK, I just logged in, I did take it out of the box today, everything is clean, got the mainshaft, O/D Unit, Soleniod, Gearswitch, some gaskets/

It is clean, it spins fine when I put the shaft in, at this point that is about all I can report.

I have not had this newer type O/D apart before, the older ones I am familiar with have a bunch of springs between the O/D and the box, don't see any on this one, are they missing or are they not supposed to be there?
Click to expand...

Excellent news!

Mine hasn't arrived yet. I assume that what you received was as per what was pictured in the auction?
 
This is a little late, but I thought it interesting for this thread. Can you guess who may have offered up this response to the question posed him? (some of you may have read this somewhere recently).

Q. What is your favorite TR modification and why?
A. I really loved the overdrive transmissions and used them in all my cars except the Spitfires and the GT-6.



This was a response from....

....Kas Kastner in the most recent issue of British Motoring (www.britishmotoring.net)

Just an FYI
 
From the guru himself! Thanks for posting that, very interesting.

Also regarding OD, you'll note that few topics will elicit more opinions and observations here than ones about overdrive.

It's a relatively expensive mod, but most certainly one of the best IMHO.

I wonder why Kastner didn't use OD in racing Spits and GT6s??

Odd . . .
 
If I were to race, though I don't, cept when driving
to work...(California living), I'd want to know just
what gear I was in and no chance, I mean no chance of
bumping in or out the wrong way, one way or another.
Might just be some racing guys will come along saying
they use the overdrive all the time. We'll see.
 
My OD has arrived from New Zealand: I have to pick it up at the post office tomorrow. The seller sent it on 27th. December, so that is what I call quick shipping. (It sure beats the heater motor guy in NH who shipped it to me on 17 November, and it has still to arrive!)

Let's see, 27 Dec to 2 Jan is 6 days, i.e. 144 hours, and New Zealand to LA is 6500 miles, which is an average speed of 45mph - and it's not even in the car. I think this bodes well ...
 
jjbunn said:
(It sure beats the heater motor guy in NH who shipped it to me on 17 November, and it has still to arrive!)
Click to expand...
Julian- I wouldn't count on the heater motor showing up at all.
 
DNK said:
jjbunn said:
(It sure beats the heater motor guy in NH who shipped it to me on 17 November, and it has still to arrive!)
Click to expand...
Julian- I wouldn't count on the heater motor showing up at all.
Click to expand...

I wrote November, but meant December ... so there is still hope!
 
My overdrive unit arrived as well. Looked a lot like
a frozen turkey: Plastic bag covering; smaller
parts stuffed down inside the opening. Was ready to
get out the thermometer.

The unit looks good; pretty clean; turns smooth,
though I didn't install the main shaft when I checked
this.

Received: Overdrive unit; gasket; solenoid; switch.

Did not receive installation instructions, though seller
said he would include them.

So, I suppose I will be needing some wiring and
a switch of some type to go onto the steering
column or something of the kind, right?

Haven't looked back in this post yet, but there
was a mention of a vendor selling these types of
parts. I made a mental note of that, but since I
really didn't know, really, what would be included
with this purchase, I let it go at that. Guess I'll
be looking back.

Thanks,
 
2wrench said:
Received: Overdrive unit; gasket; solenoid; switch.
Click to expand...
Should also be a mainshaft and angle drive for the speedo in there.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Did not receive installation instructions, though seller said he would include them.[/QUOTE]Hard part is installing the OD on the gearbox; the rest is pretty easy.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]So, I suppose I will be needing some wiring and a switch of some type to go onto the steering column or something of the kind, right?[/QUOTE]Yup, that's the idea. The wiring is pretty simple, so no need to try to buy a sub-harness, IMO. Some of it might even already be in the original harness (at least it was on my Stags). Please don't be tempted to leave out the lockout switch on the top cover, though. It's all too easy to forget just once, and the OD will be junk if you back up far enough for it to engage. There is a one-way sprag clutch in the tailhousing that will break the clutch ring & housing if it's forced to turn the wrong way.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Haven't looked back in this post yet, but there
was a mention of a vendor selling these types of
parts. [/QUOTE]The parts are available from most of the usual suspects, tho I don't know of anyone else putting together packages like Quantum Mechanics does.
 
What I have in my package is:

1) J O/D
2) Solenoid
3) Angle Drive (I asked him to add this, at extra $$$)
4) Lockout switch
5) Early type mainshaft
6) Gasket


Everything is in pristine condition, and well packed. It did indeed look like a Christmas Turkey!

I already have the O/D escutcheon for the steering column, and the O/D wiring harness (for an A-type, but easily modified).

What I need to find from elsewhere is an O/D column stalk switch ... does anyone have one spare they want to sell?
 
Perhaps you will need a relay? (I am not familiar with J-Types so perhaps not) and as you note, the stalk switch.

I also added a discreet indicator light to glow when OD is engaged (for night driving).

You may want to modify the gearbox tunnel to provide some access holes for common maintenance and adjustment (unless 6s come with those holes in place).

The switch is readily available from the usual vendors. FWIW - to any adding an OD to a TR4 or for whatever reason needing the OD switch -- the one usually supplied is the TR6 flavor which works fine but has a black stalk rather than the chrome stalk. I found I could peel off that outer black covering and the shaft underneath was shiny metal. Not quite chrome but very bright. I cleasr coated it to keep it shiny and you would have to look very closely to know it is not chrome.

Randall had recommended a slo-blow fuse on the power to the solenoid to protect it should the pull-in coil fail to disengage. Seemed like a good idea so I added one.
 
Geo Hahn said:
Perhaps you will need a relay? (I am not familiar with J-Types so perhaps not) and as you note, the stalk switch.
Click to expand...

I don't think the relay is needed for the J (but I have one if not)

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
I also added a discreet indicator light to glow when OD is engaged (for night driving).
[/QUOTE]

Did you just wire the bulb in series with the lockout switch? That was how I was planning on doing it, and then mounting the bulb on the dash support console (I have a spare hole).

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
You may want to modify the gearbox tunnel to provide some access holes for common maintenance and adjustment (unless 6s come with those holes in place).

The switch is readily available from the usual vendors. FWIW - to any adding an OD to a TR4 or for whatever reason needing the OD switch -- the one usually supplied is the TR6 flavor which works fine but has a black stalk rather than the chrome stalk. I found I could peel off that outer black covering and the shaft underneath was shiny metal. Not quite chrome but very bright. I cleasr coated it to keep it shiny and you would have to look very closely to know it is not chrome.
[/QUOTE]

My headlamp stalk switch is chrome. My flasher switch is the black ... a replacement part. So I suppose the '71 TR6s had chrome stalks.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Randall had recommended a slo-blow fuse on the power to the solenoid to protect it should the pull-in coil fail to disengage. Seemed like a good idea so I added one. [/QUOTE]

Could one use a bulb/light in place of the fuse? That would serve two purposes: some current protection and also a O/D engaged indicator?
 
I don't know if a bulb would give you the reliable protection that a designed fuse would. Here is the set-up I used:

The kit -- inline fuse holder from Ace & fuses from Radio Shack:

SFu%20Fig%201.JPG


Put together to easily connect to the harness between the relay (on an A-Type) and the wire you choose to fuse:

SFu%20Fig%202.JPG


In place, well everything still works and I am more protected:

SFu%20Fig%203.JPG


This is what I used for an indicator lamp:

https://www.hotrodwires.com/cart/tek9.asp?pg=products&specific=jnrqhqj8

I was able to find it at the local CarQuest.
 
jjbunn said:
I don't think the relay is needed for the J (but I have one if not)
Click to expand...
Not needed. The J-type solenoid draws much less current than the A-type does (2 amps versus roughly 20 amps for pull-in), so no relay needed. Not that it would hurt if you want to use one, but it's not necessary.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Did you just wire the bulb in series with the lockout switch? That was how I was planning on doing it, and then mounting the bulb on the dash support console (I have a spare hole).[/QUOTE]Wiring the bulb in series will not work, as then the solenoid will not get a full 12v. Instead, connect it from the load side of the operating switch to ground. That offers another advantage as well, it will stay on even when the gearshift is in neutral or first (which IMO is mostly when you need to be reminded that the OD is switched on).

Geo Hahn said:
You may want to modify the gearbox tunnel to provide some access holes for common maintenance and adjustment (unless 6s come with those holes in place).
Click to expand...
The J-type was redesigned to move ALL maintenance and adjustment points to the bottom. The only operation from the top is filling the gearbox with oil.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I found I could peel off that outer black covering and the shaft underneath was shiny metal. Not quite chrome but very bright.[/QUOTE]Check out https://www.jmwagnersales.com/ltslssr.html for a cheap way to get very good looking chrome on one of these stems.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Randall had recommended a slo-blow fuse on the power to the solenoid to protect it should the pull-in coil fail to disengage. Seemed like a good idea so I added one. [/QUOTE]
That's only suitable for an A-type (or D-type). The J-type has no pull-in coil (which is why it draws much less current), so a fuse is not needed for that reason. And because of the lower current, you can just take power for the switch from the "green" (fused ignition) circuit, so no extra fuse is needed even to protect the wiring.
jjbunn said:
Could one use a bulb/light in place of the fuse? That would serve two purposes: some current protection and also a O/D engaged indicator?
Click to expand...
Nope. Again, the bulb would not pass the current needed for the solenoid. Two devices in series must split the voltage applied to them (with the lower resistance device getting less voltage). With a fuse, the resistance is basically zero, so the series device gets full voltage. But a bulb is designed to take full battery voltage (and draw relatively little current).
 
Hi Randall,

Yes, of course parallel rather than series for the bulb. I think the holiday break has fuddled my grey cells!
 
Julian, can you post a pic of the angle drive?
Guess I'll have to contact him in this regard or
shop around for one. How hard are they to find?

If you come accross parts you think I could use that
you already have, will you PM me?

Thanks,

Oh, and Randall, I did receive the main shaft, just
inadvertently omitted that part.

Thanks,
 
Ok you 2, I want 1 of you to devise a trick way to have a shift mounted switch.
 
Easy ... get the OD shift lever from a TR3 or Stag and the knob/switch from a Stag (or I think late Spit is similar). Bend or cut-n-shut to get the shape you like ... the Stag lever could probably be used unchanged (tho it's longer than the stock TR6) but the straight TR3 lever will run your knuckles into the console when you shift.

Or, what I did many years ago, just tie-wrap a push-pull switch to the lever. I put mine where I could reach it easily with my two middle fingers, while my palm cupped the knob.

You _might_ be able to drill a stock TR6 shift lever for a single very thin wire (then use a relay to control the OD), but you'd still have to cut and reweld it near the base (need two intersecting holes to follow the curve). Or, mill a groove along one edge, then cover it with heat shrink.

Finally, a really clever guy might figure out a way to stick a battery-powered transmitter in a shift knob, but I think that's a little far out.

Angle drives are readily available in the US, just kind of expensive. Something like $60-70 from the big 3, last time I looked. I'm running a used one I won on eBay for $25.
 
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