Speedo Drive

[davidbolam]

Good Morning,

i have currently got the engine and box out of my car (5 speed) whilst it is away at arch being re-skinned and long front. 

Last night I was cleaning the gearbox and engine and decided to check the speedo cable and drive. On the gearbox itself where you screw the 90 degree angle drive to it ( the brass threaded part) it is loose and I cant figure out how to tighten it.

im worried there is either nothing inside or that it wont work when it goes back together?

also when i try to attach the 90 degree angle drive the threaded part on the gearbox will just turn. I have a quill to insert to replace the broken allen key

Ive never managed to drive the car as it is a restoration that turned out to be a shaped like a banana hence the new front.

Can anyone tell me how to tighten the brass bit? someone on the facebook group said there should be a circlip. i cant see one anywhere (which could be the problem)

Has anyone got any photos or diagrams please?

[Jonathan Kay]

Private Message sent.

Jonathan

[John Vine]

It's a while since I played with angle drives and speedo cables, but IIRC this is what you should have:

A worm drive in the tail of the gearbox, with an oil seal and a hole in the end to accept the square-section quill. 

A brass "top hat" adaptor.  This sits in the gearbox aperture, on top of the oil seal.  The top hat is held in place by a circlip (there's a groove for this running round the inside of the gearbox aperture) but is otherwise free to rotate.  The threaded section attaches to the collar on the angle-drive.

Tightening the angle-drive collar onto the top hat can be a real pain.  You could try gripping the top hat with a pair of long-nosed pliers as close as possible to the gearbox to stop it rotating.  Or you could remove the circlip and the top hat completely, attach the collar, replace the whole and reinsert the circlip.

... to replace the broken allen key.

I didn't quite follow that bit?

JV

[John Vine]

This photo from the Haynes Ford Sierra Manual shows how the standard cable is held in by a circlip: 

The top hat mimics the flange on the cable.

JV

[davidbolam]

Thanks for the replies. i had a go at dismantling it this morning. Ive since bought a pair of circlip pliers as it looks like its not propertly seated

 

David

[paul richards]

If I am understanding you correctly the "brass top hat" is meant to be loose. It is held in by a circlip but this doesn't hold it rigid. It will still spin and move about. To remove the angle drive I hold the top hat with a small screwdriver or similar and undo the angle drive by hand or pliers (if necessary) on the knurled part. 

[SM25T]

The problem with the top hat moving is it allows the wires to chafe and wear through.

[Bricol]

The other problem with it being free to rotate is that it can come loose . . . say when you are reversing out of a parking space in a car park in the Black Forest . . . suddenly notice that the speedo doesn't work a mile down the road after it fell off . . .

Mine has had a collection of tie-wraps around it to try to stop it, or hang on to it if it does it again - 18yrs later, they still seem to be working :)

 

[John Vine]

...it allows the wires to chafe...

Are these the wires emerging from a speedo sensor?   The OP refers to a "speedo cable".

JV

[SM25T]

Ah ... yes ... expensive electronic sender.