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Speedo fluctuates

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AUSMHLY

AUSMHLY

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I purchased a new speedometer cable from Moss. It has printed on the cable, UK.

0-40 the needle fluctuates. I've checked...no kinks. I've taken the right angle drive out of the tyranny and greased that. The connection into the tyranny and into the cable seem good. I played with the connection at the gauge. Seems good there too. Tried it with the connection tight and a few screws back at the gauge. Makes not difference.

Speedometer gauge was rebuilt.

What's the chance that's its the cable? What is the correct length? If the cable is off by, 1 or 2 inches, would it make a difference? Cable is greased and seems OK.

So, whatss sup wid dat?
Roger

And now for something completly different....
 
Did this start after you had your transmission out several times ? Perhaps the copper washer is now missing between the angle drive and the O/drive. If missing this washer, it will bind the angle drive until it breaks. Your speedometer will also fluctuate ....
I should also ask if this flucuation is why you had your speedometer repaired but the repair didn't help ?
 
I would talk to whoever rebuilt the speedometer, but my guess is that they will say the likely culprit is that the inner cable is too long. Maybe by only 1/4 to 3/8 of and inch.
 
OK, here's the story.

One day after installing the tyranny and Speedo cable, I noticed that the odometer was not turning. When I got home I took a look under the car and noticed that I have sandwiched the cable between the car and the transmission tunnel. The load bent the cable and the end which goes into the right angle snapped off. My bad.

I ordered the new cable from Moss, which was stamped UK. (the good stuff?) Put the Moss cable in, now have the fluctuation problem.

As I said, I removed the right angle, to check it. Copper washer was there, and I greased everything. Played with the other end of the cable that goes to the gauge too.

No problem with the old cable, before the end snapped. No fluctuation.
That's my story and I'm sticking to it.

So, what is the correct length. That may be the problem?
Or maybe something happend to the right angle?
Roger
 
Hey Roger,

Photo is just too funny and unfortunately distracted me from offering any helpful advise. BTW when mine is not fuctuatating it's amazingly accurate and within 1 to 2 MPH of GPS.

Gonzo
 
Hey Gonzo,

Dude, your killing me.

"BTW when mine is not fuctuatating it's amazingly accurate and within 1 to 2 MPH of GPS."

OK, Gonzo, so yours is working very well, 1-2 mph of GPS.
And your's Roger isn't....neaner neaner neaner.

Dude, I know where you live. And you've seen how fast I can be on my Pandacycle, taking that turn in the sand box. I'll be over in 10 minutes and you can tell me in person how accurate your speedo is.

Cheers,
Roger
 
Roger -

If the cable binds on the back of the speedo, you will always get this type of fluctuation. If the cable is too long by even a couple of MM it can cause this problem because the cable will push the magnetic spinning cup into the needle assembly.

I would recommend taking your car down to a local speedo shop and giving them your current speedo cable and asking them to make it a quarter inch shorter and see if that makes the difference. Change the cable only, not the cable sheath. It's actually not the length of the cable itself that's the problem, but the length of the cable with respect to the sheath.

Also the other reader mentions the copper washer you put between the angle drive and the gearbox. This washer seems, as Dr. Evil would say "inconsequential," but the reality is this little washer can make a huge difference with a wobbly speedo as well.

Best,

Alan
 
Moss cable are historicaly too long. Measure it against the old one as Healeynut says not the outside but the relationship of the inside to the outside. You can grind it down and round the end a little. Hopefully you did NOT lubricate the cable.
Gonzo, I'm with you. Mine is correct except when it goes hinky for two seconds. I carry a GPS that is right on with the speedo.
Morgan Hill this weekend? Its a 500 miler for me so I'll check the odometer against the GPS.
 
AUSMHLY said:
OK, here's the story.

One day after installing the tyranny and Speedo cable, I noticed that the odometer was not turning. When I got home I took a look under the car and noticed that I have sandwiched the cable between the car and the transmission tunnel. The load bent the cable and the end which goes into the right angle snapped off. My bad.
......
......
So, what is the correct length. That may be the problem?
Or maybe something happend to the right angle?
Roger
Click to expand...

On the drive home from the transmission shop, the speedometer cable was pinched ( not turning ).
This ruined the insides of the angle drive ! You replaced the speedometer cable with a new one from Moss ( I am using one of those that I got less than a year ago and it works fine ) but that angle drive was also damaged on the ride home from the transmission shop. ...
You have said that you tried loosening up the new speedometer cable connection on one end. If the inside piece was a little too long, loosening it up would have corrected the problem.
My money is on your angle drive being the cause of the speedometer jumping . ... But your money will have to by a new one from Moss and they are not giving them away .

Ed
 
Before I buy a right angle. Can anyone please measure the inside cable for me?
Thank you.

I'll be at the Morgan Hill show too.
I look forward to meeting my fellow Healey owners there. Please stop by and say hello.

Roger
 
Try spinning just the speedo, then with the cable, and so on, with a drill and see if you can spot the problem.
 
It is not the inside cable length but how much it sticks out of the out of the casing because that determines how much it inserts into the speedo. Are you re-using the outside sheith with a new inside cable? If so then the inside length is important.
 
Hey ASUMHLY,

Yup, Autumn Classics Meet is a must. We will be there Saturday for the dinner get-together. The AH field will be split: side-curtain and roll-down window varients. Look forward to seeing you there.

With regard the the speedo cable length, I believe this is a topic covered in N. Nock's Tech Talk.

Gonzo
 
tahoe healey said:
It is not the inside cable length but how much it sticks out of the out of the casing because that determines how much it inserts into the speedo. Are you re-using the outside sheith with a new inside cable? If so then the inside length is important.
Click to expand...

TH, no. New unit from Moss.
 
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