Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing 1994 +8 Speedometer cables.

Hi Everyone, I need to replace the speedo cables on my 1994 +8 due to the speedometer needle flicking. I’ve tried cleaning/lubricating the original cables with no benefit so the next step is replacing them. Unfortunately I seem to have met a dead-end.

My car has the usual setup of a VDO speedometer connected via a long upper cable (102cm), [current Morgan part number MED0680], to a road speed sensor, a small box in the engine compartment on the bulkhead. Then it has a short lower cable (59cm), [current Morgan part no. MED0690], from the sensor to the gearbox, (LT77). This set-up has never been altered since the car came out of the Factory. The replacement cables I have had from Brands Hatch Morgans and Melvyn Rutter with these part numbers do not fit due to one end of each cable being different to mine.

Below is the upper end of the sensor with the thread down near the green cable.



Below is the lower end of my long cable on the left; the Factory cable on the right has the shorter fitting which won’t reach the sensor thread.



Below is the gearbox takeoff.



Below is the lower end of my short lower cable on the right and the Factory cable on the left.



Below is the inside view, my fitting on the left has a deeper recess.



Below, my cable fits flush to the gearbox take-off and can be clamped in place.



Below, the Factory cable bottoms-out on the raised centre of the take-off and cannot be clamped in place.



I have emailed the Factory but I have been told it is a bit hit and miss if and when I might get a reply! I know of Speedy Cables in South Wales who will make cables but I have been told by a Morgan dealer that, at the present time, one can expect a wait in excess of 4 months.

Has anyone with a +8 built around 1994 successfully replaced their speedometer cables with something off the shelf rather than going bespoke? Part numbers gratefully received.

A couple of other suppliers you could try... both can (or could, not used 'em for a while) make what you need

DJA Auto International Ltd
Unit 1
Glover Street
Smallwood
Redditch
Worcestershire
B98 7BG

and...
Speedograph Richfield Ltd
Darlton Drive
Arnold
Nottingham
NG5 7JR

This is probably a silly question but how do you know it is the cables causing the speedometer needle to flicker?

Britmog ... you're right, it can be other things .... but they're hard work and expensive so I'd always try the cable first. 😁

Usually a bit of the twisted inner gets loose and snags on the outer, winds up the inner a little bit til the extra strain frees it, then repeats and repeats causing the needle flicker ... will fail eventually.

K

Years ago I had the same problem with my plus 8 with an almost identical setup. I contacted both speedycables and speedograph. Both said they could help but I had to send my cables to them to act as templates. I was idly fiddling with the road speed sensor when I noticed it was very stiff. So I managed to open it up and found it full of semi solid grease. After cleaning and reassembly the flickering needle problem disappeared. Opening the sensor required drilling out the rivet heads which was easy enough but reassembly required the rivet shanks to be drilled and tapped for set screws

Yes my Land Rover suffers from that particularly for the first few miles in cold weather due to thick oil/grease in cable, when needle osciillates 10 mph. I think the needle bearings are contributory though as it also reads low until warmed up.

Thanks CooperMan, I'll give those two suggestions a go if I get no joy from the Factory.

Yes Grumpy2, I remember some one on here stripping down the road speed sensor, could even have been you! I wasn't sure from the report how they reassembled it. I could cope with machine screws so I will have a look at it, thanks.

Hello,
both lower speedo cables are not correct. Even the old lower cable is wrong, but nevertheless sold many years from Morgan as well.
The lower part of the lower cable needs a kind of recess to be centrated on the transmission. There has to be a small outside recess which cares about centrating
of the cable on the speedo drive gear. When there is no recess the needle of the speedo can flicker, as you have it.
Since around half a year or a year Morgan delivers correct lower speedo cables now.
Unfortuantely I don`t know how I could post pictures here, for to point how the lower cable has to look.
Regards
Frank
Morgan Park Hamburg

Thank you Frank.

Yes there is confusion here between Smiths and the later VDO speedo cables and then there is all this grease stuff. The MMC mistakenly supplying the wrong part is interesting. Thank you for that as well. These things explain why people are having so many problems.

Speedo cables should not per se use grease, though perhaps a tiny smidgen of white lithium grease is less bad than other gobs of other greases. Ideally, speedo cables should use powdered graphite...though there is a thin graphite lubricant available recently. I haven't tried it. Aside from the grease,and the wrong cable from the MMC, another common reason for a joyously bouncing speedo needle, is binding..at either end but more commonly at the speedo. The cable has to be placed PRECISELY in the right place into the speedo which is a pain considering the severe u-turn it has to take to get there. Happily, it can be tested before one commits by install the cable into the speedo., taking the other end and spinning it in reverse with a battery driven drill. If you have a steady or steadier cable, connect the other end. [/quote] If that proiduces a jumpy needle, you know where the problem is.


Is the image below what you wanted to post?

gomog

P.S. BTW, I haven't kept up. Is Lutz still working with you?

Well, in the last couple of weeks MMC must have gone back to their old ways!
Picture no. 6 in my original post shows a good flush fit on the gearbox takeoff ready for clamping with the original cable. Picture no. 7 clearly shows Morgan's latest offering which wouldn't fit flush and could not be clamped in place.

Sometime in 1994 Land Rover changed the Rover v8 gearbox from the LT77 to the R380 which presumably was used until 2004 when the +8 was discontinued. It may be that a different cable fitting was used for the R380 and there was only a small number of LT77 compatible cables around.

The quest continues.