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Speedo does not function

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T

Tinster

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Ctypty's speedo does not function.

I replaced the speedo cable assembly
(Moss Motors) while I had the tranny
cover off for the carpet install, last weekend.

The speedo does not function. I disconnected
the new cable from the speedo gauge and the
inside square cable does not rotate when the
car is moving down the highway.

I pulled on the tag end of the square cable and
it would not slide out. So probably not broken.

I have 15 minute hydraulic lift time reserved
for later this morning. Any ideas what I should
look for? Or do?

thanks

D
 
Is it in properly where it connects to the gbox?
I'd check that first
 
Alan- that is my first thought also but
what should I look for? The install seemed
very straight forward.

Insert square cable, tighten housing nut.
How could I have meeded that up?

D
 
Does it spin freely by hand at the speedo end? If so, it may not be in properly or it is broken.
Or it could be binding at the tranny end. Try loosening the the trans. end and spin at speedo endto see if it goes into place.
 
While we're on the subject, the speedo in my 3 bounces around dramatically at most speeds - is this likely a kink in the cable or something in the gauge?
Thanks,
k
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Insert square cable, tighten housing nut.
How could I have meeded that up?[/QUOTE]

Likely you didn't /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif

Check its not broken at the tranny end (which is where mine went).
Then check it spins freely.
If these 2 criteria are met, try attaching the tranny end to a drill and spinning it slowly - see if the cable spins at the speedo end.
If it does, hook it up to the speedo and spin with the drill again. If the speedo moves, then it's the drive gear in the tranny.
If not then its the speedo.
You get the idea - isolate the components individually.
My bet is the cable either binding or broken.

Oh and wifegonnakillme - yours I'll bet good money is that the cable is binding somewhere.
 
IIRC, you need to spin the cable with the drill motor in reverse to get the speedo to move upward.
 
Thanks Guys!

I get the hydraulic lift at 11:15 AM,
So now I can make best use of the "air time".

d
 
Tinster said:
Insert square cable, tighten housing nut.
How could I have meeded that up?
Click to expand...



<span style="color: #993399">Leet's see, let me count the ways.....</span>
 
Diagnostics indicated a functioning square, inner cable.

I originally installed the cable directly as it arrived.

Today I pulled out some more length on the tranny
end and reinstalled the cable and hooked up the speedo.

Bingo! I now know that 3000 rpms on Crypty registers
65 mph on the speedo. In the zone with highway traffic
in the fast lane.

Thanks one and all

d
 
Aloha,

Regarding instrument needle bounce, it can usually fixed or minimized by lubricating the cable. I find that powdered graphite is a good product to use for this. I would first remove the cable form the flexible tube and wipe it down the remove any caked grease and check for damage. If everything is fine reinsert the cable while shooting in the graphite as you go.

The speedometer or tachometer are usually fine and don't require anything action as long as the drive spins freely. A quick test is to remove it from the dash and spin it with a drill as others have discussed.
 
AHA- The old argument starts anew. Shouldn't 3000 be 60 mph??
 
Hey Andy!

It could also be the slightly oversized tires I have
on the car. A little bit more distance is covered per
tire revolution.

So for local driving conditions, I know I am safe
from the policia radar guns at 3000 rpms since that
is expressway high speed lane traffic flow.

D /bcforum/images/%%GRAEMLIN_URL%%/savewave.gif
 
Tire size has NOTHING to do with the reading on the Speedometer...only on ACTUAL road speed. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
martx-5 said:
Tire size has NOTHING to do with the reading on the Speedometer...only on ACTUAL road speed. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
Click to expand...

Good point. The speedo is measuring the 'speed' of the prop shaft, so any change in tyre size or diff ratio would affect the actual speed and not the measured speed (relative to engine RPM that is). I just about fell into the tyre trap while reading this myself. It must be a Friday.
 
Friday the 13th even. DOOH!, it's my brothers birthday. I better go get that book I've been meaning to buy for him.
 
martx-5 said:
Tire size has NOTHING to do with the reading on the Speedometer...only on ACTUAL road speed. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
Click to expand...


"But officer, they told me on British Car Forum that my new tires didn't affect my speedometer reading."

I don't understand all that, but I do know that when I installed my overdrive, and new tires (slightly different diameter), I had to do the flag-on-the-speedo-cable-roll-it-down-the-street-59.5ft and give this info to Nisonger to calibrate my speedo.
 
What I was suggesting is that, for example, Tinster's tachometer might be a bit tired and reading a bit low...or that it and/or the speedometer were never totally accurate to begin with. Certainly the latter is a strong possibility, given that relatively few cars then or now had/have absolute precision, "certified" gauges.

I always wondered about "certified" speedometers one would see in police cars. Were those speedometers "recertified" as tires wore down or as they were replaced with a different brand (or possibly even size) of tire? /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
TR6BILL said:
martx-5 said:
Tire size has NOTHING to do with the reading on the Speedometer...only on ACTUAL road speed. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
Click to expand...


"But officer, they told me on British Car Forum that my new tires didn't affect my speedometer reading."

I don't understand all that, but I do know that when I installed my overdrive, and new tires (slightly different diameter), I had to do the flag-on-the-speedo-cable-roll-it-down-the-street-59.5ft and give this info to Nisonger to calibrate my speedo.
Click to expand...

That's because your tire size does effect your actual speed but it doesn't change the reading on the speedo. They had you do the tire thing so that they could get your speedo to more accurately reflect your indicated speed to your actual speed.
 
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