Speedo drive, where is it?

[nicbowman]

Hi

I know it is on the gearbox somewhere, any clues before I lie on my back in the cold?

Ta


Nic

[spend]

That one just tells the ecu if you are moving.

The drive for the speedo is off the diff.

Should save you a bit of crawling/creeping..

Dave

[nicbowman]

Ta Dave.

Nic

[shpub]

Not on a 4.3 Griff .... LT77 cars usually have a gearbox sensor behind the rear drive flange and under the remote.. Held in place by a two pronged fork.

[nicbowman]

Hi, now dirty, still looking! It is not on the diff or drive shaft, no tooth wheels or such like. There is a small sensor on the left hand (nearside) tail end of the gearbox, could be? It is a 4.3 pre-cat, Rover gearbox. Anyone got a picture or other description.

Thanks again.

Nic

[spend]

shpub said:

Not on a 4.3 Griff .... LT77 cars usually have a gearbox sensor behind the rear drive flange and under the remote.. Held in place by a two pronged fork.

Is that all 4.3's or just early pre-cats, Steve? I understood that the early 500's LT77/GKN had the layout I described (as does my Chim) I assumed the others would also, or is is a case of what the factory felt like on the day..

Dave

[nicbowman]

Hi all, I have removed somthing that looks like a geared drive, held on the rear of the box by a two pronged thingy. Looks suspiciously like a speedo drive. Thanks for the advice all.

Cheers.

Nic

[shpub]

spend said:

shpub said:

Not on a 4.3 Griff .... LT77 cars usually have a gearbox sensor behind the rear drive flange and under the remote.. Held in place by a two pronged fork.

Is that all 4.3's or just early pre-cats, Steve? I understood that the early 500's LT77/GKN had the layout I described (as does my Chim) I assumed the others would also, or is is a case of what the factory felt like on the day..

Dave

Yes but Chims are not Griffs. They were about 1 year after the pre cat Griffs and I suspect it was also a case of what was lying round at the moment. Typically the LT77s used the gearbox sensor, T5s used the diff mounted sensor. But not totally set in concrete.

Edited by shpub on Saturday 3rd February 17:59

[antonyj]

nicbowman said:

Hi all, I have removed somthing that looks like a geared drive, held on the rear of the box by a two pronged thingy. Looks suspiciously like a speedo drive. Thanks for the advice all.

Cheers.

Nic

Nic , sounds like you have found it.
Be careful when you look for a new spare, some are 4 pulse per revolution and some 8.
I got mine from rimmer bros.
Does it say something on ot like DRC8007A? Seem to remember this being stamped on the body somewhere.

IIRC the 8 means 8 pulses, so it may be 4007A for four pulse.

Some people say you cant test them without a oscillscope, but I used an analogue meter measuring resistance across the terminals and the needle definately swung when the unit switched.

The problem with mine wasnt actually the sensor inside, it was the connections as the wires go into the unit, unfortunately not repairable.

Edited by antonyj on Saturday 3rd February 18:45