TR2/3/3A TR3 Speedo cable

[Meyer'sTR3]

Hello all you British roadster fans. Before I get to my question, just want to say I am finally back in the game!:wink-new: I have owned a few Healey's and one TR3 over the years beginning in high school with a 60 Healey 3000 I purchased for $450 and a set of stereo speakers. Most fun I ever had and ever will have on four wheels, partly because I was only 17 at the time. Fast forward to today, I am retired and recently acquired a 1960 TR3A that is unrestored but a real nice driver that turns a lot of heads. Every where I drive this thing people stop and stare. Going down the freeway people roll down there windows and yell at me. When ever I park it someplace someone will stop and take pictures. It is almost embarrassing, but I have to admit enjoyable all the same. I can't believe how fun it is to drive this thing. I had forgotten the feeling of how these old british roasters feel when yanking them around some curvy country road. What a blast! It's been a long time, and I can't really remember how my Healy handled, but this TR3 is a joy in the curves. Pretty stock suspension except for the added sway bar. Anyway, on to my question. The speedo cable is absent. Missing in action. That's how I got it. When I went to order a new one at Moss there was an option for one that goes on a overdrive model and one without overdrive. Well, this car does have a working overdrive, but it is an added overdrive. The original car did not have overdrive. Sooo....do I need to get a speedo cable for what the original non-overdrive car had, or now that it has an aftermarket overdrive, should I get the "overdrive speedo cable"? What does the overdrive have to do with the speedo cable? Does the added overdrive attach where the original speedo cable goes? I'm a little in the dark on just how these added on overdrives are installed. Any help will be appreciated. :eagerness:

 

[NutmegCT]

Congrats on your new TR3.

If it were mine, I'd order both drive cables, and see which fits. Most suppliers (Moss, TRF, etc.) will let you return an item if it doesn't fit.

My two cents!
Tom

 

[CJD]

Welcome to the forum!

The non-overdrive cable came out the left side and went forward. It is relatively short. The OD cable exits the right of the tranny, and goes forward, up and over. It is relatively long.

I can bet the non-overdrive cable will not work. It is likely the OD cable will, and if it doesn't, it at least gives you a starting point to go from.

 

[TR3driver]

Just to amplify a bit, the non-OD gearbox has a long housing at the back, with nothing inside but a plain shaft and the speedometer drive. When installing OD, either by the factory or afterwards, that housing gets removed and the OD goes in it's place. Since the speedometer drive needs to be located behind the OD, it gets moved to the very back of the overdrive.

In short, you need the OD cable. The routing is "interesting" as well; the cable actually comes out through a hole in the side of the transmission tunnel and runs through the handbrake boot before going back through the floor in the same hole where the handbrake lever sticks up. You will probably have to remove the tunnel to install the cable.


From there, it makes a wide turn under the floor and runs out against the RH frame rail. Up the firewall and then across on the ledge in front of the battery. There should be a clamp with a screw to hold it to the ledge (which your car may be missing); and as I recall there is also a clip under the floor somewhere to hold it down there. It looks strictly Rube Goldberg, but seems to work surprisingly well in practice.

You'll probably also want a new grommet for where the cable goes through the firewall (in front of the driver). Old grommets usually are not stretchy enough to install over the cable end without tearing. (It's tough even with new ones.) I find that coating it with silicone spray a few minutes beforehand helps.

Check how far the new cable extends at the speedometer end. Some of them are too long, which puts pressure onto the speedo mechanism and leads to early failure. With the inner cable pushed into the outer cable as far as it will go, the inner cable must not protrude more than 3/8" from the outer, measured at the flange inside the nut.


I would also check that the speedo turns easily (use a small screwdriver or similar to spin it). If it is stiff, it will probably get hot in service, bind, and ruin your new cable. A very small amount (no more than 2 drops) of WD40 or similar applied at the edge of the shaft inside the opening might help, but most likely you will have to either disassemble, clean and lubricate the head yourself; or send it off to one of the many services that will do it for you (for a price).

 

[Meyer'sTR3]

Thanks to all for some very good info.