TR2/3/3A TR3A choke geometry questions

[Don Elliott]

In Fig. 7 on page 7 of Bob Shaller's book, the rod connecting below the front carb has the "yoke" on the side of the brass choke arm which extends downwards from the carb body. It is shown on the side closest to the inner fender. I have mine like this. The judges a TRA will check that it's is like this. With the cotter pin installed to hold it all in place, the cotter pin ends will scratch the outer covering of your wiring harness every time you pull the choke out. So I have made a curved sheetmetal plate over this to protect the cotton covering on my wire harness.

 

[jdubois]

TRF P/N RFP128

Ta!

 

[TR3driver]

The judges a TRA will check that it's is like this.

Ok, Don, I'll bite ... why do they accept Bob S. as an authority over the diagram in the factory "Practical Hints" publication?

 

[jdubois]

Thanks for the better close up. I still don't understand this picture. It looks like the fork isn't even hooked up, as the lever arm looks too far toward the rear of the car for the holes to line up.

 

[Don Elliott]

Randall - I had mine connected like the black and white you show (see in my photo how mine used to be) and I had to use both hands to pull the choke knob out a half inch. Now I have it like Bob shows and I can pull out the knob three inches with one hand and there is no resistance. I could never figure out which way was the best, but I know that my 1958 TR3A came brand new with the yoke under the front carb exactly as everyone would have thought to be the most logical engineered way - that is - the yoke around the both sides of the brass part extending downwards.

And it worked way back then just fine.

 

[ekamm]

And Randy maybe he just wants his engine to run well. After all there aren't any there when I start my car.

 

[TR3driver]

Well, I guess the factory photo IS open to interpretation. My interpretation was that the cable wasn't actually attached in the photo, and should go on the near (outboard) side of the lever, with the clevis entirely on the inboard side of the lever. That's the way mine is, and it works very nicely.

BTW, here is Bob Schaller's diagram.

 

[ekamm]

Tell me then what was the purpose of the fork?

 

[TR3driver]

Hard to explain, but the forks do actually keep the pins from twisting sideways, even though they don't straddle the levers. The pins are a relatively loose fit in the levers, so they would twist otherwise.

All I know for sure is that it doesn't work nearly as well with the forks straddling the levers, the way it looks like it should be.

 

[Andrew Mace]

It also seems obvious (at least to me) that the forked-end design, on threaded rod, provides an easy means of length adjustment of that rod if necessary!

 

[mountainman]

Don,I have the same problem with pulling out the choke[two hands]. As soon as I get my car back from the body shop I am going to fit it as per dig&pict shows. Thanks to you & Randel
WHAT A GREAT FORUM
Greg

 

[sp53]

Hi Don I am a little confused on what side (it) goes. Could you please post a picture of how you have it now.
Steve

 

[Don Elliott]

Steve - I have my choke rods and cable secured just like the sketch that Randall included. Here is a photo of mine that I just took a few minutes ago.

BTW, maybe you can also make out the sheetmetal protector I made, painted and inserted around the wire harness to keep the cotter pin from cutting into my new wire harness. You can see where already some scratches are down to the primer. I'm glad I did this. At a concours show, it'll take me about 30 seconds to remove it before the judges come by.

 

[Don Elliott]

And here is a clearer side view.

 

[TR3driver]

Sorry I don't have any photos yet, but my setup is the mirror image of Don's, at the front. Which puts the cotter pin inside, away from the harness and leaves extra room between the nut & harness.

The motion is so automatic, I had to check myself this morning ... I grab the choke knob between thumb & the side of my first finger, to pull and rotate it (so it locks). But I don't have the stock choke cable with the distinct notches; it's an aftermarket "infinitely adjustable" one from Moss.

 

[Geo Hahn]

...to pull and rotate it (so it locks)...

Whereas, I'm under the impression the original would pull and lock and you rotate it to release it.

I changed mine to the text-book version and I think made it harder to work, guess I'll try Don's (Bob's) arrangement.

...At a concours show, it'll take me about 30 seconds to remove it before the judges come by.

I'm tellin'.