1980 Jumpy Speedometer
Thread Starter
Instructor
Joined: Jun 2003
Posts: 135
Likes: 1
From: St. Pete Beach FL
1980 Jumpy Speedometer
Just replaced the Cruise Control transducer and have CC back, but also still have a jumpy speedometer. Since there are two cables, is there a way to check which one is culprit, or should I just go ahead an replace both???
Race Director
Joined: Dec 1999
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Re: 1980 Jumpy Speedometer (azswede1960)
You should check the square ends of the cable for being rounded off, if that's not it, lube the cales as good as you can and make sure the cables don't have too sharp bends, that usually fixes 99% of jumpt speedos (a worn CC transducer will cause a jumpy needle too but yours is new)
Marck
[Modified by Twin_Turbo, 2:12 AM 9/9/2003]
Marck
[Modified by Twin_Turbo, 2:12 AM 9/9/2003]
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Re: 1980 Jumpy Speedometer (azswede1960)
To test, you'll really have to have 3 test scenarios.
1) New cable from tranny to CC xducer, old cable to speedo. (testing old xducer->speedo cable)
2) Old cable from tranny to CC xducer, new cable to speedo. (testing old tranny cable)
3) new cable for both (testing new xducer)
May as well just replace both.
-Steve
*edit* Marck is spot on - lube is frequently at fault. Grease em and the jumpiness will prolly go away.
[Modified by Pacin'California, 12:31 AM 9/9/2003]
1) New cable from tranny to CC xducer, old cable to speedo. (testing old xducer->speedo cable)
2) Old cable from tranny to CC xducer, new cable to speedo. (testing old tranny cable)
3) new cable for both (testing new xducer)
May as well just replace both.
-Steve
*edit* Marck is spot on - lube is frequently at fault. Grease em and the jumpiness will prolly go away.
[Modified by Pacin'California, 12:31 AM 9/9/2003]
Team Owner
Joined: Aug 2000
Posts: 21,440
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From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
Cruise-In VI Veteran
St. Jude Donor '08-'09-'10-'11-'12
Re: 1980 Jumpy Speedometer (Pacin'California)
On my '80 4spd car that I used to have, it took one brand new cable to stop that "jumpiness". Car had about 94K on it when I replaced it. One other possibility is a worn plastic speedo gear, but it's usually the cable. :yesnod:
Safety Car
Joined: Jun 2002
Posts: 4,738
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From: Buckeye, AZ
St. Jude Donor '12-'13
Re: 1980 Jumpy Speedometer (azswede1960)
I bought one of the speedometer grease lube fittings from Mid-America. You disconnect the speedo cable, put the fitting in and pump in grease through a standard grease gun. Works really well. If it gets a little jumpy again I re lube it. I have lent this to several club members with good success.
