Speedometer fault

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Stoneporch
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Speedometer fault

Post by Stoneporch »

After going over a bump in the road my speedometer stopped working. I fitted a new cable.No difference. I ran the cable with an electric drill and the speedo worked perfectly at all speeds.I replaced the drive pin and oil seal in the gearbox. No difference. I ran two other spare speedos on the electric drill, and both seemed ok. Connected all 3 speedos to the gearbox in turn and all run erratically, with no relationship to the actual speed of the car.
All thoughts/ suggestions gratefully received.
Thanks, Stoneporch.
oliver90owner
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Re: Speedometer fault

Post by oliver90owner »

If it is running erratically, the outer icould be snagging the inner drive cable resulting in ‘wind-up’ and giving a swinging speedo indication instead of a steady one.. Only apparent, perhaps, when the speedo cable has a bend - so seems to be OK while straight. Does the odometer record correctly?
les
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Re: Speedometer fault

Post by les »

I'm at a loss as to what's going on here. There are two threads (no doubt duplicated) about this issue in the mechanical section, one has no replies, so far, and the other with one reply, so far (mine) Then the query was repeated in this section about 90 minutes later, to which there is one reply so far.

oliver90owner
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Re: Speedometer fault

Post by oliver90owner »

I noticed your post on the subject had ‘apparently’ disappeared. Same problem with another thread, but that was all in the same section...

Inners and/or outers was not included in the OP and am not sure if the poster really means doesn’t work at all or is not working properly. Hence the question of the odometer.

Now I have seen the other thread, there seems to be more information provided.

Need to wait for the OP to sort out the deatails and get back to us with some semblance of order. I note the OP was logged in this evening.
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geoberni
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Re: Speedometer fault

Post by geoberni »

The Forum that I'm a Mod on, we have a rule about making multiple posts in different Topics, which is what this OP has done.

Finger (or IT) trouble to post twice in 'Mechanical' at 8:47, but then a deliberate posting in here, 'Other', at 10:26. :roll:
What's needed is a nice Admin/Mod to merge the topics together and make some sense of all this :D
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biomed32uk
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Re: Speedometer fault

Post by biomed32uk »

Quite why going over a bump would do this not sure, but it sounds like the gear on the output shaft of the gearbox has come loose.
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The gear is not keyed to the shaft, that is just for the tab on the lockwasher.

The bad news is that to do anything about it the gearbox has to come out, so you need to be sure. Not sure if you can feed a finger in where the drive emerges from the box.
Stoneporch
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Re: Speedometer fault

Post by Stoneporch »

Thanks for the replies, gents. Sorry if I have made a breach of etiquette. 2nd posting seemed, with hindsight, to be a more appropriate site.

After running with yet more "spare" speedos giving no apparent solution to the problem, I think I've noticed that after an increasing period of sensible behaviour (currently about 4-5 miles), the speedo slowly becomes increasingly erratic. On the last occasion, returning home with a wildly oscillating needle, I instantly disconnected the speedo and connected it via a spare cable to an electric drill and watched it behave perfectly. I have, therefore, ordered a new, British made cable in the hope that the new one I bought from a different supplier last week is now the cause of the problem. As for the odometer, I am currently unable to tell whether it is recording accurately. Meanwhile I will remove my first "new" cable and attempt to get some thin oil into it.
Stoneporch.
Darren.
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Re: Speedometer fault

Post by Darren. »

I think that you have proberbly worked out the issue. i bet that its the cable. I would order the outer cable as i suspect you just got a new inner :D
P.S make sure that you have routed the cable correctly to ensure a snag free cable
Stoneporch
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Re: Speedometer fault

Post by Stoneporch »

Thanks for the interest and advice. A brief update: I have now received, and fitted, a reconditioned speedo from Charles Ware, together with a new inner and outer cable. The speedo now performs as normal for about 5 miles after which it again becomes increasingly erratic, leading my wife to comment that no other car we have owned has been able to go from 0 to 80 mph in such a short space of time. When the weather becomes less clement I will remove the gearbox and take it from there.
Regards. Stoneporch.
Stoneporch
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Re: Speedometer fault

Post by Stoneporch »

Thanks for the interest and advice. A brief update: I have now received, and fitted, a reconditioned speedo from Charles Ware, together with a new inner and outer cable. The speedo now performs as normal for about 5 miles after which it again becomes increasingly erratic, leading my wife to comment that no other car we have owned has been able to go from 0 to 80 mph in such a short space of time. When the weather becomes less clement I will remove the gearbox and take it from there.
Regards. Stoneporch.
Stoneporch
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Re: Speedometer fault

Post by Stoneporch »

Thanks for the interest and advice. A brief update: I have now received, and fitted, a reconditioned speedo from Charles Ware, together with a new inner and outer cable. The speedo now performs as normal for about 5 miles after which it again becomes increasingly erratic, leading my wife to comment that no other car we have owned has been able to go from 0 to 80 mph in such a short space of time. When the weather becomes less clement I will remove the gearbox and take it from there.
Regards. Stoneporch.
biomed32uk
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Re: Speedometer fault

Post by biomed32uk »

Not really leaving much else now, it's only the tail housing of the box that has to come off, just the whole lot has to come out to get to it.

Are you able to feed a small screwdriver in where the cable drive goes just to be sure, see if you can turn it on the shaft.

Why on earth the scroll is not keyed to the output shaft baffles me, I put some loctite on it for good measure as well when rebuilding the box prior to tightening the nut up.
Declan_Burns
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Re: Speedometer fault

Post by Declan_Burns »

My mate had a similar issue on his MG TD. The early XPAG gearbox output shafts were not keyed. The later ones were. After a gearbox failure the only useable second hand shaft available was one of the early ones. It was a matter of eroding the key slot which was not too difficult when you have an eroding machine. We eroded an oil drilling on an old BSA crankshaft with the same machine but that took ages and soon after the machine packed up! Another job on the cards.

Regards
Declan
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Regards
Declan
StillGotMy1stCar
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Re: Speedometer fault

Post by StillGotMy1stCar »

Spark Erosion Machine, everyday's a school day:-
https://www.youtube.com/watch?v=9oPmFb4liVM
Regards John
Stoneporch
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Re: Speedometer fault

Post by Stoneporch »

Thank you for those postings.
I have just returned from a 1500 mile tour of northern Europe in the Minor, using a free 'ap' as a speedometer. During the trip the speedometer became more accurate, but rarely to a reliable degree. I am resigned to removing the gearbox over the winter to resolve the problem. I should add that the Minor ran entirely trouble-free for the whole of the trip, apart from a slight leak through the front windscreen rubber.
Thanks again all.
Stoneporch.
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