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yoc
04-27-2008, 09:06 AM
Hi, I installed a complete speedo cable and speedometer but the needle still keeps jumping. What next?

Mercedesrover
04-27-2008, 09:17 AM
Make sure you don't have a kink in it. Make sweeping bends in it as you route it up to the dash. Wouldn't hurt to drip a little oil down the cable either.

I Leak Oil
04-27-2008, 09:53 AM
If it's routed without any sharp bends then check to make sure both ends are engaged in their drives properly and check to make sure the rear output flange nut is tight as the speedo drive gear is driven by nothing more than a friction fit IIRC.
Jason T.

yoc
04-28-2008, 06:05 AM
Hi, Thanks for the reply Jim and Jason. I don't think it could be the cable being kinked. I'll check the rear output flange nut. Is that the nut with the locking washer just ahead of the od?

BackInA88
04-28-2008, 09:01 AM
Hi, Thanks for the reply Jim and Jason. I don't think it could be the cable being kinked. I'll check the rear output flange nut. Is that the nut with the locking washer just ahead of the od?

NO they are talking about the nut in the center of the emergency brake drum, right over where the the rear drive shaft bolts to.
You have to remove the rear drive shaft to see it.
It should also have a cotter pin in the nut you would have to remove first before you can thighten it.

I hope this works for you.
I checked everything on mine before I finely replaced the speedo and all is well now.

Steve

singingcamel
04-28-2008, 09:52 AM
I use grafite powder, sounds like a dry cable . make sure the end in the tranny is tight

yoc
04-28-2008, 12:45 PM
Thanks guys, cable is new inner and outer. must be in tranny. thanks

Apis Mellifera
04-29-2008, 07:41 AM
Is the speedo new?
If not and if the Landy speedo is anything like the ones in my MGs, it's probably the speedo. Most Smith's speedos have a spinning bar magnet that rotates inside a shallow disc inside the speedo housing. The magnetic force drags this disc (rotates it) as the cable drives the magnet. The needle is attached to a shaft that passes through a brass friction bar and then attaches to the disc. Usually what happens is the one side of the magnet weakens and this unevenly "drags" the needle around. There is a margin of adjustment via the brass friction bar. To access it, remove the needle and face and you'll see it. The bar is supposed to dampen needle movement, so if you get too loose or too tight, the needle movement won't be smooth. It might be possible to re-magnetize the magnet, but I've never tried it. You can test the speedo by isolation with a square-drive bit in a drill. Hope this helps.

Blueboy
04-29-2008, 10:47 AM
my does the samething - I just use the GPS to tell how fast I'm going.

the speedo is fairly accurate though - it just jumps around a 5mph range.


Jaime

KevinNY
04-29-2008, 03:44 PM
Same subject, my Speedo quite working but works when I drive the cable with a drill from the transfer case end?? It started jumping around a bit, got worse then quit altogether.

LaneRover
04-29-2008, 06:25 PM
Wait.... ...some of them DON'T jump?

thixon
04-30-2008, 09:52 AM
Did you lube the cable prior to installation?

yoc
04-30-2008, 10:18 AM
Hi, cable is new inside and out bought new/completly assembled. speedo is also new. haven't checked tightness of nut behind pbrake yet.

thixon
04-30-2008, 10:25 AM
If both are new, then my guess is lube, or too small a bend in the routing of the cable somewhere. Don't use a light oil, it just drips down to the bottom of the cable over time Either use a graphite lube, or a viscuss dino lube of some type. I've used lithium grease before because I did'nt have anything else at arms reach, and it worked fine.

thixon
04-30-2008, 10:27 AM
I just notice you said you bought the cable new, already assembled. If you did lube it, did you pull the inside of the cable out of the housing and lube it that way?

daveb
04-30-2008, 12:53 PM
hi

this procedure should not be necessary if everything is assembled correctly.


I just notice you said you bought the cable new, already assembled. If you did lube it, did you pull the inside of the cable out of the housing and lube it that way?

ps 2nd gear! :)

I Leak Oil
04-30-2008, 05:41 PM
ps 2nd gear! :)
Your the man Dave!
Jason T. (now one post closer to 2nd gear!)

yoc
05-05-2008, 07:19 AM
Hi, Got to work on the rover. 1st. dropped drive shaft at brake drum, removed cotter pin, tightend nut, was tight. 2nd. removed cable at tranny, rerouted, slight bends before and after rerouting. My three screws to hold cable to tranny are slotted what fun they were getting back in. made sure cable was centered to flange. Results, needle now bounces from 0-60 mph when moving in 1st/ 2nd at slow speed. when stepping on the gas needle stops bouncing and read correct. When I installed new complete cable I didn't lube. New from RN. Last time I replaced, I didn't lube and it worked fine. Next?

siii8873
05-07-2008, 06:34 PM
Interesting, mine was working fine untill yesterday. It seems to work just fine at any speed under 40mph. when I get up to about 50-55 it starts to jump between what I think is correct and about 70mph. Corrects itself when I slow down. Very timely thread I'll need to check some of these items.
Thanks

KingSlug
05-08-2008, 01:29 AM
Try googling MG speedo repair, I posted an article over on the GnR board once but cant find it now. Those guys are alot crazier than us, but someone wrote a doc with pics of how to repair a speedo that is exactly like the rovers. A lot of it is really in depth with calcs and such but they had solutions for correcting bounce and truing the speed.

Jared

Alacrity
05-08-2008, 05:25 PM
This it KingSlug?

http://home.comcast.net/~rhodes/speedo.html (http://home.comcast.net/%7Erhodes/speedo.html)