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MG Midget and Sprite Technical - Speedo for MOT?

Might seem like a silly question but do you need a working speedometer for an MOT ? I got underneath the car to attach the speedo cable and couldn't . On closer inspection the PO has blanked off the nylon insert presumably when he raced it so it didn't lose oil. If I do need to have a speedo please tell me I can get the nylon threaded fitting out without removing the engine ! By the way it's a mk2 midget with 1275 engine and possibly original gearbox.
Thanks. Mike
m fairclough

this came up on PH recently and I 'think' the answer was no but what about your main beam warning light, etc.

have a look here and see what you think - http://www.motuk.co.uk/

I'd be tempted to fit the speedo even if not working to prevent hassle if the examiner is only going to move the car a few yards he'll (or she'll) not notice it not working (?and he'll perhaps be please to see a mileage for him to enter into the system?)

if you find out for sure let us know as this comes up every now and again
Nigel Atkins

Sorry should have said there is a speedo in the dashboard with the main beam light that works. Its the gearbox end where the problem lies.
m fairclough

in that case if the examiner is only going to move the car a few yards he'll probably not notice it not working

be nice to know for sure but I couldn't find anything when I briefly looked before (note it wasn't and isn't my car going in for the MoT)

my mate said it has to have 30 mph marked on the speedo but I don't think that relates to the MoT

they don't be testing the accuracy of the speedo (that I know of)

before you take i in I'd suggest greasing the font suspension to try to prevent any comments about 'play'

and just before going in get your engine fully warmed up and warm at the test even though your exhaust fumes aren't part of your test

a friendly nature and set of spare bulbs may help too as they don't like blackened bulbs
Nigel Atkins

Maybe they check it on the brake roller?!
Dave O'Neill2

As long as the pinion is fitted on the gearbox shaft you should be able to do everything else from underneath. There is a mating pinion and shaft which protrudes through the gearbox casing and which has a plastic moulding surrounding it. This moulding has an external thread on one end to screw into the gearbox and on the other end onto which fits the speedo cable. It has an internal O-ring which seals off around the drive pinion to keep the oil in the gearbox. I'm not sure whether this can still be purchased - I bought one secondhand as mine had a damaged thread.

If you were stopped and had a non-working speedo then that would surely be an offence. I would have thought the mot people would want to see it working although I don't believe they check the accuracy.
G Williams (Graeme)

Mike

I've probably got the parts, if you need them.
Dave O'Neill2

Dave,
I think the brake roller was covered in the PH thread, I think the answer was that the wheels aren't driven as such which makes sense otherwise the car would need strapping down

from the link I gave earlier -
Speedometer
This inspection applies to Class 5 vehicles first used on or after 01 October 1937.
A Tachograph is an acceptable alternative to a speedometer providing it satisfies the requirements of this inspection.

cars are Class 4, have a look on your MoT paper, so the speedo isn't part of the MoT test

and as far as I could tell, for the MoT at least, you don't need an odometer/mileometer or for it to be accurate
Nigel Atkins

Interesting. The examiner will note the odometer reading. If it hasn't changed from last year, might he question the speedo? The car definitely has to have a speedo (or some way of measuring its speed) to be road legal, but it's likely the examiner won't notice if it's not working. However, when the car is on the brake rollers, and the examiner is sitting inside, he may notice if the speedo isn't registering. Although the car won't be in gear, the turning of the rear wheels will make the speedo operate.

Incidentally, if the pinion gear is in the gearbox, oil won't be lost just because no cable is attached. The PO probably blanked it off to keep dirt out.
Mike Howlett

a classic could be trailed in for MoT and some classics really do only show the few miles of getting to and from the annual MoTs (! sadly) or very few miles registered or traveled each year - think of some MGBs for example

whether the examiner notices if the speedo is working or not it's not part of the MoT and he records the mileage as shown on the odometer without knowing how accurate it is everytime

I don't think it matters if the mileage is negative as long as the car isn't sold fraudulently based on a lower mileage
Nigel Atkins

Mike: the oil filler point for the gearbox is higher than the speedometer coupling so, even if the levels were marginal, there is likely to be something escaping.
When I replaced mine, there was oil on everything even though I drained the level a bit first.
G Williams (Graeme)

Thanks for all the replies I have only just had time to log back on. I would like a speedo so I might have a go at removing the threaded insert to see if I can get out the obstruction,any idea how I can get a spanner on that? Will I dislodge anything inside? it feels like something has been pushed inside and it sits flush with the end of the threads, it looks a coppery colour Im wondering whether its a 1/2 p piece. Its a bit difficult to tell peering through that "bung" in the tunnel
m fairclough

Mike (and others),
I thought there might be something in the MoT about perhaps cracked glass or damaged face of speedo or something to stop driver seeing it so I had a scratch around the VOSA site, only took about 5 mins

turns out once again I WAS WRONG, below is copy & paste of what I found plus I emailed them about anomalies with milometer reading (I'll post when I get reply)

'Speedometer not fitted / incomplete / cannot be illuminated / inoperative / cannot be readily seen by driver - (See Note 1) - (see Action 'IN')

(Note 1) – Vehicles first registered on or after 1 October 1937 are required to be fitted with a speedometer unless the vehicle is legally limited to a speed not exceeding 25mph or is one which is incapable by reason of its construction of exceeding 25mph.

(Action 'IN') – Advisory defects not considered serious enough to prohibit the vehicle. They are reported on a Vehicle Inspection Notice explained in the following paragraph –

Where Examiners find on a vehicle roadworthiness defects not serious enough to warrant prohibition, they will advise the user/ owner using a Vehicle Inspection Notice. This notice is advisory only and does not in itself prevent further use of the vehicle.

Even if not prohibitable, some of the defects may mean that the vehicle is unroadworthy and does not comply with the law. Continued use of a vehicle issued with either a Delayed Prohibition or a Vehicle Inspection Notice listing advisory defect(s) risks prosecution under the Road Vehicles (Construction and Use) Regulations or Road Vehicles Lighting Regulations and so it will be in the user’s interest to repair defects as soon as practicable after they are noticed.'
Nigel Atkins

Mike: the plastic unit comes out easily enough although you won't do it through the bung hole I don't think. It has a substantial face to get a spanner on to!

I would also play safe and drain some oil out of the gearbox just in case! If it is all complete you should see the end of the drive which mates with the speedo cable. In the plastic unit you remove you will see internally there is a lip seal* which fits around the drive pin. Moss catalogue p140 items 45 to 48. The pinion drive I refer to is item 45

* I thought that was an O ring but looking at the pic has reminded me! Same principal though.
G Williams (Graeme)

On my Midget I fitted an electronic speedo driven by a Hall effect sender on the diff. Therefore I didn't need a speedo cable so I simply left it off. No oil ever escaped from where it should have been plugged in.
Mike Howlett

My car after 10 year lay up went for MoT at Christmas. Speedo present and passed MoT. On first drive found speedo and mileometer not working. No advisories so no test of speedo carried out. Required as part of vehicle operation but down to owner / keeper and owner to ensure working correctly. Miles recorded on MoT from the mileometer which of course broke before I had car sometime.

BTW for all of you that thought the driver is responsible for the legal and maintenance side of the vehicle think again its changed since the 70's.
Dave Squire

Mike: If the main body connector is left in place then that is sealed around the little drive pinion so won't leak. I think it may well leak when you remove it however. On your back under the car particularly in the middle, which is not the easiest to reach, having oil run down your arm is best avoided.
G Williams (Graeme)

Mike,
whilst your at it you might as well do a thorough oil change on the g/box, get the old oil as hot as possible and drain for as long as possible, you could also upgrade to modern synthetic

Dave,
>>BTW for all of you that thought the driver is responsible for the legal and maintenance side of the vehicle think again its changed since the 70's.<< please do expand on this
Nigel Atkins

Looks like it might be worth having a go for the MOT if i can't remove this- it looks like loads of fun!


m fairclough

Difficult to see from the pic, but is that an alloy cap that is threaded onto the original plastic unit ?

I can't see the plastic threads in the pic so it may be capped.

R.
richard boobier

Nigel, registered keeper not driver.
David Smith

David, thanks, now I follow what was meant
Nigel Atkins

I've had a reply from VOSA and it includes a very interesting bit about the future requirements which I'll ask about -

'Dear Nigel.

Thank you for your email enquiry dated 11th February 2013 concerning the MOT.

At present a speedometer is not tested as part of the MOT (although it will be introduced in the near future).

Modification of the odometer will have no bearing on the MOT and a change in the reading between two certificates will not cause any problems.

I hope this information has assisted you with your enquiry, but if you have any further questions please do not hesitate to contact us again.

Kind Regards

Mark J Evans
Customer Service Centre
VOSA Operations Directorate
Tel: 0300 123 9000'
Nigel Atkins

My speedo hasnt worked for the last 2 mots! Another one now due. worrying thing is that the odometer will say the same figuee. . I am changing the speedo cable tomorrow but I really could do with changing the number of miles

How do I unclock the speedo?
d j kirk

Try googling it! There are several sites that tell you how to do it. I think you insert a narrow blade between the digit rings but it is all about turning them in the correct order and in the right direction.

Also this might be useful: http://home.comcast.net/~rhodes/speedo.pdf

and this (particularly at the end): http://magnetic-speedometer-repair.com/odometer.html
G Williams (Graeme)

from my post just before
>>Modification of the odometer will have no bearing on the MOT and a change in the reading between two certificates will not cause any problems.<<

they didn't say anything at the last two Mots did they

sometime the MoT will shown the last three reading but they only print off now to give people a bit of paper - it's all entered into the computer now
Nigel Atkins

I asked VOSA about the 'will be introduced in the near future' bit here
>>At present a speedometer is not tested as part of the MOT (although it will be introduced in the near future).<<
but I've not really got a reply to that only want happens now so I've given up and if anything crops up in the future no doubt we'll here about it then

here is the reply to my enquiry about the 'will be introduced in the near future'

'Dear Nigel.

Thank you for your email enquiry dated 19th February 2013 concerning the MOT.

Please find following the response to your enquiry from our PVSM team:

The speedometer test is detailed in Section 6.7 of the current MOT Manual which can be viewed on-line at http://www.transportoffice.gov.uk/crt/doitonline/bl/mottestingmanualsandguides/mottestingmanualsandguides.htm

It is also important to know that testers are not required to drive a vehicle to ascertain that the speedo works. However, should they have a need to carry out a road test or decelerometer test and the speedo was seen to be inoperative, then it would fail.

Odometers are not testable so this is not an issue, other than recorded mileage variations when selling a vehicle on.

All the best

MOT Standards Team

Roadworthiness and Testing Policy Group

I hope this information has assisted you with your enquiry, but if you have any further questions please do not hesitate to contact us again.

Kind Regards

Mark J Evans
Customer Service Centre
VOSA Operations Directorate
Tel: 0300 123 9000'
Nigel Atkins

Thanks for all your investigations Nigel, it sounds like I can put off crawling underneath the car for a little while longer

Mike
m fairclough

Mike,
please note the bit
>>However, should they have a need to carry out a road test or decelerometer test and the speedo was seen to be inoperative, then it would fail.<<

and if the Police stop you the gauges do have to be functioning, how they'd tell if you're at a standstill is another matter but if they had to drive or be in the car with you they might notice but I'd guess if that was the case you might have bigger worries
Nigel Atkins

Finally got round to tackling this job , anyone know what size socket I need to get on the pinion . Tried all my stuff and think a thin wall socket may be only option .The po seems to have filled it with araldite


Mike Fairclough

Mike

It is 1-1/8"

I have a socket you can borrow and a pinion, if you want it.

I also have a slimmer socket than the one in the photo.


Dave O'Neill 2

Cheers Dave I'll drop you an e mail
Mike Fairclough

This thread was discussed between 10/02/2013 and 26/05/2017

MG Midget and Sprite Technical index

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