TR2/3/3A TR3A inner speedo cable too long at trans.

[SPACER]

My post TS 60000 TR3A (non Overdrive) has a new speedo cable from VB.

The inner cable square end is 3/4" long protruding from the outer aluminum fitting. This is at the the trans. end.
Problem is, my trans sq. hole is only 5/16" deep.
I assume I can cut off about 1/2" with a dremmel tool, hpefully without unwinding the strands.
This does not seem like a lot of engagement but I hope it will work.

The cable fits fine at the speedo end with good engagement & no binding.

Anyone else have a problem of this nature & how did they fix it???

Thanks,
Bob

 

[TomMull]

I have had no problem cutting the square ends of speedometer cables. However, 1/4 inches into the transmission does not seem enough. Is it possible there might be a piece of the old on still in it?
Tom

 

[TR3driver]

There is certainly some problem there. 1/4" is barely enough to get to the square portion of the bore; the cable should go in by at least an inch or so. That allows for the relative lengths of the inner and outer cable to change, as the cable is bent around curves and so on.

I just checked an original TR3 gearbox, and the hole in the trans is at least 1.5" deep. (My probe was only that long; if memory serves the hole is actually closer to 2".)

If this was an overdrive, I'd suggest you had the drive gear from a Volvo (which uses a very slightly smaller square on the speedo cable). But I've never heard of that happening with a non-OD trans (although I suppose the gear would fit).

 

[SPACER]

I agree, there should be more engagement


Don suggested I try a dental pick which I have on hand.
I tried the dental pick; no luck but I think something is in there.
Bentley manual page 180 shows item 22 locating screw.
I think if I loosen this screw, I can pull out item 18, the speedo drive.
I can work on it on my bench easier
Both Bentley & Haynes use the same diagram & numbering.
I think item 21 the screwed adaptor is the offending part & I cannot get at it with a wrench in the car.

Edit: Now that I think about it, the blockage may be in item 18, the speedo drive.
I hope I can pull it out from outside of the gearbox extension. I am doing this too early in the morning.
Am I on the right track?

Bob.

 

[TR3driver]

Right track, yes. Remove the retaining bolt, then remove items 18, 19, 20, 21 as a unit. It probably won't want to come out easily; one approach is the screw the cable end back on and then use a pry bar (or better yet a pair of them) under the edges of the cable nut.

(This photo is of a TR6 gearbox, but the process is similar)

 

[SPACER]

Hi Guys,

Yes Randall, that is exactly what I did.
I cheated & used vise grips gently to break the seal.

Thanks for all the good advice.

Took most of the day but got it fixed.

Here's how:

Remove trans tunnel (16 bolts) in car to gain access to speedo gear bushing locking bolt.

Much easier to remove speedo gear & bush now

Yes the shaft was full of the remains of a broken cable.

Using a drill vise & small drill press I drilled out the remains to a depth of 1 1/8" , using a jewellers screw driver to bend strands. then re drill to remove stuborn strands.

Repeat drill & pick about 10 times as well as sharpen drill a few times to get to that depth..

It was more work than I expected but it is all buttoned up & I am happy now.



Thanks again & I hope these posts help others.
Bob