S3 Speedo pickup on the gearbox

[Jed-S]

Done a search but can't find it so has anyone got the part number for the speedo pickup on the gearbox? Mine is leaking and the GF isn't impressed with the oil marks on her drive.

Jed

[mep12345]

IIRC removal of this (if it is the electronic type) requires a partial strip of the box as it only comes out once the selector shaft and a couple of other items are removed. The Granada Haynes manual covers the strip down if you want to check

[Jed-S]

mep12345 said:

IIRC removal of this (if it is the electronic type) requires a partial strip of the box as it only comes out once the selector shaft and a couple of other items are removed. The Granada Haynes manual covers the strip down if you want to check

Not on mine - remove one bolt and it pulls out and has a cog on the shaft. And yes, it is the electronic type.

[mep12345]

Jed-S said:

mep12345 said:

IIRC removal of this (if it is the electronic type) requires a partial strip of the box as it only comes out once the selector shaft and a couple of other items are removed. The Granada Haynes manual covers the strip down if you want to check

Not on mine - remove one bolt and it pulls out and has a cog on the shaft. And yes, it is the electronic type.

You're right had a look at Haynes manual this morning and the box strip takes it out at about step 4, but that could just be because it is easy to do it then rather than the other stages need to be done first. I assume you have removed yours from what you say. Therefore how does it seal - gasket, o-ring etc?

Mark

[MickS2]

Jed-S said:

Done a search but can't find it so has anyone got the part number for the speedo pickup on the gearbox? Mine is leaking and the GF isn't impressed with the oil marks on her drive.

Jed

When I replaced mine back in 2004 the Part no. was F1012923. The parts man claimed the old part was obsolete so you have to fit the drive gear from your old one onto this one (dead easy). Also the electrical connector is different but that is easily fixed by fitting the one from your old sender.
The only problem was that it cost 65 quid!

Fitting was easy, but I already had the exhaust off, could be difficult with it on.

[spivvy]

i got one from the local ford dealers it is a granada electronic speedo sensor you will have to redo cables as connectors are different and the colouring of the wires is different also i can't remember part number but can check if you wish

[Jed-S]

MickS2 said:

When I replaced mine back in 2004 the Part no. was F1012923.

Excellent - thank you very much. Just need to find one now but having the part number helps.

Jed

[bil]

recently did a search for type 9 gear box seals, can up with this link url http://www.transmission-rebuild-kits.co.uk /url

[mep12345]

Is anyone going to get these details added to the alternative parts list? If not I'll submit them but I'll be working on trust and would hope that someone with the info in front of them would do it to assist the rest of us later if we need the info.

[Bobhon]

Sounds like just the thread I need. I've just brought a TVR S2 . Great car, but eth spddeo always reads massively UNDER, e.g 60mph on speedo is actually 72mph on the GPS.
It had a recon gearbox before I brought it and I am thinking that it has the wrong speedo drive in the gearbox for my electrical speedo?
Does anyone know what it should have? How I can identify what it's actually got? And how to get hold of the right one, part number, etc?

Any help much appreciated.

[Gerald-TVR]

Hi Bob

Welcome to the forum, where abouts in the West Mids are you based??

[Jed-S]

I can't remember the number of teeth on the gearwheel on the transducer but you do have to take the old one and transfer it to the new one so that could be where something has gone wrong.

Before you head down that route I'd suggest checking the following (not knowing anything about your car):

Are the tyres still 205/60-15?

What RPM do you get at 50mph/60mph in 5th? The answer should be close to 2000 and 2500rpm. 3000rpm should give you 73mph. If the rpm reads correctly then I'd suspect you might have a diff but you'd need a 3.09 one to pull 72mph when you should be doing 60 and I can't recall a Sierra/Granada 3.09 diff.

Does the speed change when you turn on the fan/lights? If so then check out the infamous yellow connector under the steering column cowl near the ignition switch. My experience of this connector is that it made the speedo read fast but it could go the other way I guess.


good luck
Jed

[Bobhon]

Gerald, I'm based in Solihull

Jed, thanks for your help. I've done 3 runs at each indicated speed of 40, 50 and 60 mph and I'm getting a consistent error where 10 mph indicated rise gives 13 mph actual (GPS) rise.
Hence I suspect that the speedo pick up is wrong, say giving 10 pulses per gearshaft rev v an expected 12? I guess that when the recon gearbox was fitted they put in the incorrect bit in the gearbox, but I can't go back to check as it was the previous owner who had it done.
But I don't know if it's an easy change or complete gearbox strip out to fix it? Or what the right one should be?
Heater on heater off, etc make no noticeable difference. Wheels and tyres are standard so no change in gearing from this source. The revs you give in 5th seem about right with what I'm getting, so I suspect that the gearing is standard throughout.

I've googled the Speedo Healer which would seem to do what I want and at about £80 it's probably the cost of a new transducer anyway. The manufacturers in the USA have identified the part number of the kit I need and I'll get a cost and delivery time for it tomorrow.

[Jed-S]

Bobhon said:

But I don't know if it's an easy change or complete gearbox strip out to fix it?

I found it easier to access with the exhaust removed but someone suggested going in from above though the gear lever hole. There is a smallish bolt that needed removing and then the unit could be slid out - but it was a pain to slide out on mine.

Unfortunately I don't recall the number of teeth on the gear wheel.

[Jed-S]

Bohon,
I fitted the new speedo pickup to the gearbox last night and the drive gear had 14 teeth on it. There are pis on my site under yesterdays date.

Jed

[Bobhon]

Jed

Just looked on your website and the plastic gear bit of your drive is VERY different to mine. Mine has a lot more teeth and has a spigot coming out of the bottom of the gear which runs in a bearing in the gearbox housing.
The electronic aluminium casing looks the same.

My drive gear has 24 teeth on it and gives about a 10% under reading on the speedo. The Ford parts book lists one with 22 teeth.....BUT it's obsolete. The 2 in 22 ratio difference would make up the 10% I'm looking for.
No scrap yards have any drive gears out of an S2/3/4, say that they go like hot cakes. So I'm guessing they are almost as rare as Sherpa front indicators?

Now I have brought a 22 tooth normal cable drive gear and am having the top machined out to drive the electronic speed transducer (like yours). It's good to have a friend with a milling machine.

I'll let you know how it goes when I've fitted it.

[PompeyTim]

Looks like you're well on the way to getting this sorted, but if not I just noticed that TVR car Parts are now stocking the speedo drive gear for the princely sum of £3.56...

http://www.tvrcarparts.com/pages/partdetail.asp?id...

[Bobhon]

Tim

And I only paid £19 at my friendly local Ford dealer, for the wrong one that I'm having to have machined up.

But looking at the link mine isn't like that anyway? It has about twice the number of teeth and a long spigot (30mm or so) sticking out of the bottom.

I don't know if the 1990 S2's had some non standard type of drive, but it wouldn't surprise me.

[Bobhon]

Okay, so the red speedo drive gear on the right is the 24 tooth one that was fitted when I brought the car and gave a 10% under reading error on the speedo .
The brown one on the left was a cable drive 22 tooth gear that I brought from my local Ford dealer, part number on the invoice is F1546881.

The equivalent 22 tooth electronic speedo drive gear is sadly obsolete and likely to become as costly as a new front indicator, if you could ever find one.

This one then had the middle machined out by a friend with a lathe/milling machine (handy eh) and an aluminium adapter made and araldited in place.
I fitted it today and went out for a calibration run using my GPS as the REAL speed. And the speedo is now accurate throughout the range (well up to 70mph anyway) with a dead on reading at 30mph and only a 2mph error at 70mph .

Now I can get on with fixing all of the other things on the car .