Speedo cable series 2 with 948

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Birchall
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Speedo cable series 2 with 948

Post by Birchall »

Hi,

My 53 series 2 has the early speedo (in front of the steering wheel) and has had a 948 engine and matching gearbox fitted.
I have bnought a new speedo cable, but I must have bought the wrong one, the speedo end seems fine but the gearbox end seems to have the wrong size threaded connector?

I looked through all of the usual parts specialists and they don't seem to list one, so I thought that they might all fit the 948 gearbox?

Does anyone know if I need to get a cable made or where I can buy a new one? or should a standard one fit?

Also do I need to worry about the ratio of the speedo drive? Will the speedo read correctly with this combination of speedo and gearbox, the reason I am asking (even though the car has had this combination for a while) is because I am replacing the speedo head, the one in the car was (for some reason) one with a black face and I want to fit a replacement that I bought that is the original colour (remember that this is not the usual central speedo, it is the earlier smaller off set speedo.)

Thanks
Steve B

bmcecosse
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Re: Speedo cable series 2 with 948

Post by bmcecosse »

I can't answer about the cable, although I'm sure this must be a common conversion. Check the TPM number of the black speedo against the 'correct' one you plan to fit. I suspect the black one may have been fitted to get the correct readings - there is a considerable difference in the speedo drive revs between the two gearboxes. I don't know if the early drive can be fitted to the later gearbox. I'm sure someone who does know will be along shortly!
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Birchall
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Re: Speedo cable series 2 with 948

Post by Birchall »

bmcecosse wrote:I can't answer about the cable, although I'm sure this must be a common conversion. Check the TPM number of the black speedo against the 'correct' one you plan to fit. I suspect the black one may have been fitted to get the correct readings - there is a considerable difference in the speedo drive revs between the two gearboxes. I don't know if the early drive can be fitted to the later gearbox. I'm sure someone who does know will be along shortly!
Hi bmcecosse,

Thanks, as usual you are always an active forum member and always quick to try to help!

I suspect that I may therefore have to keep the black speedo after all. Not a big problem and the black speedo has the advantage of having a trip meter!

I even thought of swapping the faces over, but that would only work if the numbers are in the same place (and I would be covering the trip reading! (I might have a look and see if it is a possibility

All I need now is to find out about the cable

Cheers
Steve B

mike.perry
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Re: Speedo cable series 2 with 948

Post by mike.perry »

As far as I am aware all the speedo cables are interchangeable. Normally changing boxes would not affect the speedo reading which is dependant on the final drive ratio. However the 803 box has a 2/9 speedo drive pinion ratio compared to the 5/13 of the 948, 1098, 1275 boxes.
The tpm of a Series 2 speedo, both types is 1000. The only other speedo to fit the early Series 2 is the Series MM speedo which has a tpm of 1600, the same as the Series MO Oxford. The only other possibility is a Morris Six or the Wolseley versions of the MO which I have not yet checked but which I imagine would not be easily available.
In conclusion I would suggest trying a Series MM Speedo and see how it goes but check your present speedo against a sat nav so that you have an accurate bench mark
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dalgrae
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Re: Speedo cable series 2 with 948

Post by dalgrae »

I also had this problem with my 1953 early series 2 I purchased a new cable from the Morris Centre Bristol as I intended to replace my existing cable as the speedo was erratic up to 30 ish MPH and then have the speedo serviced , the threaded part at the g/box end needed to be at least .100 inch bigger in dia ,I returned the cable to the MCB they had a spare adaptor handy which screwed straight onto the cable , so I do not know ,I refitted the existing cable.My g/box appears to be original so maybe there are a couple of different sizes
Birchall
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Re: Speedo cable series 2 with 948

Post by Birchall »

As usual from this great forum, LOTS of very useful help, thanks everyone.
Yes my connection on the gearbox is slightly bigger than the connector on the new cable tgAt I bought.

I will try to get an adapter although with this being a reasonably common swap )I thought) I was hoping that I could get a cable.

I will contact a few of the many parts specialists and see what happens.

Thanks
Steve B

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Re: Speedo cable series 2 with 948

Post by 54woody »

mike.perry wrote:The tpm of a Series 2 speedo, both types is 1000...the Series MM speedo which has a tpm of 1600
What is the tpm of the later cars which used the 948 engine and gearbox? My recently purchased 1954 traveller is fitted with a 948. The PO did tell me that the speedo works but is not accurate. I've only driven the car around the block thus far so I don't know how far off it is. I was planning to replace the speedo cable as the one that's on the car looks like it's had better days so I'm interested to hear what solution you come up with.

1954 Series II Traveller
bmcecosse
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Re: Speedo cable series 2 with 948

Post by bmcecosse »

Should be 1508 or thereby.
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mike.perry
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Re: Speedo cable series 2 with 948

Post by mike.perry »

TPM is dependent on the final drive ratio not on gearbox ratios, provided that the speedo drive gear to pinion ratio is constant in the gearboxes. This holds true for the 948, 1098 and 1275 boxes which all have a ratio of 5/13 but not the 803 which I am informed has a ratio of 2/9, or the 918 box which I have not managed to extract the speedo drive from yet.
The 803 with a diff ratio of 5.375/1 has a speedo TPM of 1000, the 918 with a 4.55/1 diff has a TPM of 1600, 948 also with a 4.55/1 diff has a TPM of 1504 and the 1098, 4.22/1 diff has a TPM of 1408.
There are a selection of Mini sourced speedos for 3.9 and 3.7 diffs and larger tyres but in practice I have found that with a 3.9 diff and slightly larger diameter tyres the 1408 TPM speedo gives the most accurate reading.
I would be interested in the findings of others with different speedos checked against a sat nav.
There is a table of speedo applications on http://seriesmm.mmoc.org.uk/caridentifi ... tification
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bmcecosse
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Re: Speedo cable series 2 with 948

Post by bmcecosse »

But no-one has answered the OPs question about a speedo cable to fit the 803 gearbox ! Surely this must be a common thing??
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mike.perry
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Re: Speedo cable series 2 with 948

Post by mike.perry »

Can't answer about the 803 cable and box but I have both the original cables with brass fittings and the later cables with alloy fittings. I have just been out to the garage to check them, both cables are the same length and both fit a 1098, small 803 and 918 speedos. They all fit a 1098 and 918 gearbox.
Last edited by mike.perry on Thu Jan 19, 2012 9:53 pm, edited 1 time in total.
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Birchall
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Re: Speedo cable series 2 with 948

Post by Birchall »

bmcecosse wrote:But no-one has answered the OPs question about a speedo cable to fit the 803 gearbox ! Surely this must be a common thing??
Thanks!

I have emailed a few of the parts companies (Wares, ESM, etc.) without much luck.
Scott from ESM replied quickly (as he always does) stating that they only stock std cables, but suggested good old Speedy Cables (I have used them in the past for tricky combinations and they are very good, but I just assumed that this would be a relatively common one and so I didn't think I would have to get a one-off made)

So I will keep looking around
Cheers
Steve B

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Re: Speedo cable series 2 with 948

Post by bmcecosse »

So the next question must be - can the 948 speedo cable drive be fitted into the 803 gearbox ?? Is the scroll on the output shaft the same in both boxes - and just the gear that runs against it slightly different??
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Birchall
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Re: Speedo cable series 2 with 948

Post by Birchall »

bmcecosse wrote:So the next question must be - can the 948 speedo cable drive be fitted into the 803 gearbox ?? Is the scroll on the output shaft the same in both boxes - and just the gear that runs against it slightly different??
Not sure about that.

I have the 948 gearbox not the 803.

Steve B

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Re: Speedo cable series 2 with 948

Post by mike.perry »

I would imagine that the pitch of the teeth and drive would be different
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Re: Speedo cable series 2 with 948

Post by bmcecosse »

Well - if it's a 948 box - then the standard speedo cable should fit! Or - do you have an 803 box with a 948 remote extension grafted on the end???
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Birchall
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Re: Speedo cable series 2 with 948

Post by Birchall »

bmcecosse wrote:Well - if it's a 948 box - then the standard speedo cable should fit! Or - do you have an 803 box with a 948 remote extension grafted on the end???
Hi,
No, it is a standard 948 box.

But good old Speedy Cables seem to have the answer. There are two cables they stock for this combination. One with a three quarter inch connector and one with a seven eighths inch connector.
That certainly sounds like the cause of my problem, there wasn't much difference but it definitely wouldn't fit.

I may be wrong (I often am, just ask the wife) but on the 53 a few things seem to have changed during that year, including thigs like the interior etc. and the guy from Speedy said that this other cable is listed as relating to cars in the second half of 1953.mine is an August build and so that makes sense too.

So I have ordered the other cable (part number DF1118) from Speedy and I will let you know how I get on when I receive it.

Thanks for the help though it is appreciated.
Steve B

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