Speedo Bounce -The Final Word (Hopefully)

Thompatruck · Post by **Thompatruck** » 26 Jun 2003, 19:02

I, like most older Citroen owners have a speedo bounce [:(]and have decided to fix it.
After reading the vast amounts of postings on this subject I'm confused!
Realising there is no 100% answer I'm asking your opinions are as to the cause and solution of the problem
From what i've seen the options are....
Changing the speedo cable (upper/lower/both)
Jamming an LHM seal into the back of the speedo head (What does LHM stand for[?])
Changing/cleaning the sensor on the gearbox
Pinning the speedo cable down within the body
New speedo head (Don't think it's this one)
It's got to the stage where I have a +/- 40mph bounce and when I accelerate the speedo goes down! (not all the time!)
I'd appreciate any help, sorry to re-cover old ground, but I could do with a hand working things out before I start![:D]
Mark
'95 1.9TD ZX (Speedo head changed 45k miles ago at 51K)

Post by **RichardW** » 26 Jun 2003, 19:30

Dunno about the speedo - you'll probably need to do all of them[}:)] - but LHM stands for Liquide Heuile Minerale which directly translates to Liquid Mineral Oil. It's what us up and downers put in our systems....[:D]
Richard

Bob Smith · Post by **Bob Smith** » 27 Jun 2003, 00:30

A few weeks ago I checked a BX speedo head on the bench using two different upper cables. There was a considerable difference in the speedo action between the two. One cable could be twisted more than the other, and it was this one which caused most speedo flicker. A few weeks ago someone on another board reported on his BX16v that the flicker was considerably reduced by fitting a genuine Citroen part. I suspect the real reason for the flicker on RHD cars is the increase in length over the LHD version. Maybe some of our LHD members ,(Anders?) could comment.
To be pedantic, according to the Citroen workshop manual LHM stands for Liquide hydraulic minerale (Mineral hydraulic fluid)
Bob

AndersDK · Post by **AndersDK** » 27 Jun 2003, 01:05

Yoy're right Bob -
It's definately related to the RHD long cable runs & sharper bends.
In fact some wellknown RHD specific problems exists on BX :
pedal box cracking -
speedo cable problems -
clutch cable problems -
- never seen/heard of these problems on LHD species in Scandinavia.
BTW : there used to be speedo cable "connectors" around for the Rally people - used to insert accurate trip counters for precisely tracking nasty test track maps during drive. These connectors was also found as angle connectors (a simple small crownwheel angle gear).

alan s · Post by **alan s** » 27 Jun 2003, 07:15

I have no problem believing that one cable will give better performance than another due to the "drag" factor.
I have seen the suggestion of oiling the inner cable which I have always been led to believe by instrument repairers to be the biggest 'no-no' that can be done to a speedo cable due to the fact that the construction of the cable means that inevitably, given time, the oil will find itself into the speedo head & will actually cause variations in readings rather than prevent them.
Wear, dust & oil can & will all contribute to this problem & I agree that the LHD/RHD conversion & subsequent cable extension does nothing to alleviate the problem. I did a speedo cable on my BX 16V a while back & took note of a few points & sent them to a guy to add to his website; this was what I discovered which has worked OK for me.
Scroll down to find the part applicable to the speedo refitting along with a couple of tips associated with it.
http://www.btinternet.com/~weird_world/citroen.html
Alan S