Speedo cable on 3.8 RH/drive

[Echezeaux]

Can anyone show me where the speedometer cable enters the firewall on a 3.8 RH/Drive, top or bottom hole ?

I tried to stop the needle waiving, so I removed the cable,cleaned it, checked for kink, found some oil in the sleeve, gear box side. I cleaned that too according to the manual, but not much indications on how to run it behind the motor.
Any help appreciated. And maybe a picture or two ?

Many thanks in advance.
Thierry

Edit : Looking on Angus Photobucket, bottom hole looks like the right one .

[1954Etype]

Thierry, on the left hand side of the engine stabiliser mounting bracket, there is a hole where a spring cable retainer is fitted for the cable (not used on the LHD cars). This might aid you in ensuring the cable run is correct. (You might want to verify this on Jag-Lovers though).

Angus

[Echezeaux]

Thanks a lot Angus, I will check Jag lovers again.

Thierry

[38E]

On my 3.8, the cable comes up the left side of the gearbox, attaches to the left side of the stabilizer bracket by means of a steel clip, then comes across behind the engine and enters the bulkhead between the wiper motor and the bellows about 1" up from the bottom.

The RHD cable is slightly longer than the LHD cable. I know because I was sent an LHD in error at first.

[Echezeaux]

Many thanks Clive for the advice, the cable follows the proper route now .

Thanks again for your time.
Thierry

PS : Clive, do not forget ...

[PhilBell]

Can anyone tell me the correct length of inner cable that should protrude from the outer at the angle drive end please? It's a Moss box 3.8.

Brief history is that after years of tolerating a jumpy needle I had the speedo head and angle drive rebuilt, and fitted a new cable. After a few joyous miles with a smooth, steady speedo reading there was a brief clicking sound at the speedo head before the needle dropped to its rest stop. After having the seized speedo head and broken angle drive repaired I ordered a new cable, then another, then another... Each time I had problems with them being either a bit of a snug fit in the speedo (which can cause binding and damage), or too long at the angle drive end to allow the outer cable/sheath to but up properly. The latest one looks too short.

The lengths of protruding inner cable at the angle drive end one my various cables have been:

1. My original cable (though clearly replaced in the past): 9/16in
2. Replacement cable 1: 13/16in
3. Replacement cable 2 (different supplier): 11/16in (still 3/32in too long so I sent it back)
4. Replacement cable 3: 5/32in (too short?)

Without a period original cable for comparison I've nothing to judge the latest replacement against, and I don't want to risk another speedo/angle drive failure.

[mark10337]

according to this post http://etypeextravaganza.com/?page_id=80
it should be 3/8" into the speedo.

Speedograph richfield can make them to specification, or take one of theirs if you haven't already tried them as a supplier.

They reassuringly list different parts for the 3.8 and 4.2

The booklet Smiths Instrument Care Guide in the KB (viewtopic.php?f=16&t=700) has details about the drive cable - but not it's length. If you know what the correct length should be, you can always order just that inner shaft from a supplier.

[PhilBell]

I have a problem whereby my new speedo cable seems to fit the speedo head properly and angle drive (at the gearbox end) individually, but when all three are connected up it's impossible to turn the angle drive.

If I connect the cable to the back of the speedo head, it's easy to turn the far end of the cable anticlockwise by hand quickly enough to make the speedo needle move. If I disconnect the speedo head, but connect the the angle drive to the cable, it's easy to turn the angle drive by hand in order to check that it makes the cable turn.

However, I noticed that when I turn the angle drive it pushes the inner cable out at the speedo head end, which would push the nylon insert on the inner cable hard against the speedo head, explaining why it becomes impossible to turn.

Having had one speedo head failure and two angle drive failures previously I want to make sure that everything is operating freely before I fit it to the car this time. I'm now on my fifth speedo cable, and no two have come with the same length inner cable.

Has anyone been through this and found out what's wrong. Over-length speedo inner cable seems the obvious culprit, but could the rebuilt angle drive be at fault?

[PhilBell]

Found a new old stock cable for a 3.8, still in the Smiths box, at Beaulieu on Saturday, so hopefully that will solve my problems. Inner cable protrudes 3/8in at the speedo end, 7/8in at the angle drive end.

[marc]

so perhaps before fitting the cable you could measure and give us the exact cable length, for our future questions?
all the best
Marc

[PhilBell]

I'd already fitted it before I saw your request. But beforehand I did measure the full length of the outer cable, which was 5ft, if I remember correctly.