Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Speedo woes

Nope .... not that my swimming trunks are too tight! 🙂

Coming home from a drive this afternoon and my speedo, which had been working fine, froze at 40 mph ... on slowing it didn't want to shift then came down in a series of jumps ... seems to work ok up to about 30mph and sometimes reads above 40mph but, referencing the rev counter (and the telegraph poles whipping past) is well under-reading. I'm thinking it's the speedo itself rather than the drive or cable as I can't see how the cable could make it freeze at 40 for a mile and then drop in clunky stages ...though there's the slight possibility of the cable end slipping in the drive ... if anyone's had similar or has suggestions I'd be pleased of the head's up before I get into pulling things apart in the next few days.

Cheers

K

Ps ... 1975 crossflow 4/4

My first Land Rover (from 1966) would gradually show a reducing speed as miles clocked up on a journey (we're talking 30 + miles).
Turned out to be the drive from gearbox and an ever stiffening mechanical cable. Come to a stop and the speedo would spring up to a high speed then drop back to zero as the cable unwound.

Had a few speedo issues over the years with mine!

One problem was the path the speedo cable was taking - the bend was too tight which caused binding. Easy fix - re-route

Another problem was the right angle speedo drive on the gearbox. Went through several before getting a decent one from speedograph (now defunct). Although it started on the 4 speed, it transfered easily to the 5 speed - thread here: https://www.talkmorgan.com/ubbthreads.php/topics/562407/speedo-drive-replacement#Post562407
Also cut a larger access hole ot the gearbox tunnel to make it easier to fanny about.

Another set of issues was with the speefo drive gear in the gearbox itself. If I remember I'd lost a couple of teeth and had to replace. Easy job in situ, after I'd cut an access hole on the other side of the gearbox tunnel.

Final issue was realising the gearbox main shaft drive gear was wrong which involved stripping the entire gearbox back end down to replace the gear.

Even now, the speedo over - reads by about 8%

The first thing I'd do is remove the speedo drive from the back of the speedo so it's in the cab and go for a drive. If it spins well, then fingers crossed all OK! Also, see if you can hold it lightly when driving - mine span freely but as soon as I put a tiny bit of resistance on the cable it stopped spinning (the quill was slipping in the angle drive).

Not had an issue with the Speedo itself (although the MGB one did fail, and ended up replacing as plenty of spares on eBay)

Assuming you still have the gear drive Speedo - and it’s stuck despite the cable not turning… sounds like a Speedo gauge issue.

Yes my 60 year old Land Rover does this, particularly when cold, despite newish speedo cable, often reading very low then sticking. Once a few miles have passed though it becomes increasingly more responsive and accurate particularly in the summer. It appears to be the needle pivot likely compromised by old gummed up lubrication.

Get a Td5 mate, no such worries with electronic speedos!

My Morgan speedo used to do similar shenanigans, it was caused by a strand in the cable breaking free and getting tangled. I fitted a new cable and routed it carefully so now it just wags gracefully giving me a reasonable approximation of the speed.

Thanks Gents .... plenty there to check out ... after yesterday's lovely day it's grey and rainy so I'll slope off to the workshop and work through them.

I'll let you know how it goes.

K

Good luck!

I can tecommend these people who did some work on mine. Quick and not expensive.

https://www.speedycables.com/ - we used to use these guys when they were based in London.