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Triumph TR6 - and ON to the overdrive unit...

I have an overdrive unit on my 73. I looked under there and POOF, there it is.

It's not hooked up. No solenoid, but the lever is there. What's to stop me from making a mechanical connection to the lever that actuates the OD unit and using it that way (assuming it's functional)?

I'm making an assumption here (I know, I know) that one does not need electricity to the OD unit itself.

Is this a mechanical overdrive or an electric one? Obviously my knowledge of British OD units is sorely lacking.

Many thanks in advance,

Oh, by the way, I got all the lights working very nicely. Contacts all burnished, lights dependable, grounds tidied up.

And the flipping HORN quit working.

Jim Deatsch

Nope, it won't work. You're going to have to swap it with my '73 4-speed. Sorry. I'll even throw in a horn if you pay shipping.
Brent B

Hi Jim

Don't know if you have this may help with the horn. Go down to the TR wiring and find your 73 print off. Best thing since sliced bread. Again thanks to Dan.

The Dr.Of Darkness Lucas strikes in strange ways. No beep beep? Usually he toasts the lights on a pitch black road in the rain? You must live right.

From description of O/D likely A-type both need solenoid and wires. Whys it unhooked??? Be cautious.

I will report Brents abuse right away as per the disclaimer. Its standard practice to pay shipping if your swapping a horn for an overdrive. What a guy?? :)


Bill Brayford

I restored a '71 over the past year or two, starting with little car and little knowledge. This board is always helpful, and another excellent source has been

Under the technical section, there are detailed instructions WITH PICTURES. I've already been thru carbs and brakes there, going from zero to fixed. I don't have OD, but they have an OD article so its worth checking.

Good Luck,
Mark Hauser

You guy are amazing.

Well all except for Brent. If he thinks for a MINUTE that I'll pay the shipping he's sadly mistaken. Laughing madly here.

By the way, I fixxed the horn. So there.

So, you're saying that it takes more than just moving the lever on the OD to make it work? There are OTHER electrics in play her as well?

Bill, that's just what I was looking for. Thank you.

Mark. Thank you for the link as well. I will look into that.

Again, thanks for the info guys.

Jim Deatsch

Hey Jim--Got a '73? Then you have a J O/D with electrohydrualic actuation on 3rd and 4th only. Yes, there are interlock switches on the gearbox cover to lockout the O/D when in reverse, 1st and 2nd. Never, never, never reverse with the O/D engaged; the unidirectional clutch will be destroyed.

Rick O.
Rick Orthen

Yes Rick, it is a 73.

So if I set it up so that it could not engage OD in reverse, 1st and 2nd then it wouldn't be an issue?

I merely wish to see if the OD is functional by pulling (pushing?) the engagement lever (the one that is moved with the solenoid) BEFORE I spend the money on the solenoid and go through the switches and building the harness etc.

Thanks again,

Jim Deatsch

So if it doesn't work, you won't consider rebuilding it? Word of advice: you'll enjoy the O/D almost as much as a SMOOTH run up to 6K on the tach. I suspect it's inop since the PO left the solenoid off; maybe just the solenoid was broken? Guess you could put the rear end up on stands and run it in 3rd at idle and push the lever to see if O/D engages. If not, then I'd troubleshoot the lockout switches (haa, you'll have to remove the tunnel for that!). Check lube level first.

Good luck.

Rick O.
Rick Orthen

Does one exercise the clutch whilst shifting UP into OD?

The lube is ducky. I've filled all the appropriate fluids to their appropriate level with my very own, former oil pumping device, M1. Works duckily for filling those hard to reach gearboxes and differentials don'tchaknow.

Removing the tunnel indeed!

Jim Deatsch

Jim, I don't always press the clutch when engaging my O/D (j-type) as it is not needed but I do it just because knowing the way mechanical things are, the less shock, the better. Don't really know if it helps, but at the cost of a rebuild on O/D, it can't hurt.
w Holtzclaw

Sounds like a plan to me.

Thanks for the reply. Mine is an A type but I'd wager it couldn't hurt to disengage while engaging.


Jim Deatsch

This thread was discussed between 05/08/2003 and 06/08/2003

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