Crazy speedo problem

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Joshpow
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Crazy speedo problem

Post by Joshpow »

I got a speedo question. What makes a speedo read fine to 25, wiggle to 30, fine to 40, wiggle to 50 and then smooth out from there on? From 25-30 and 40-50 my speedo on the 72 jumps 3-4 mph. All other speeds are smooth as silk. Got any idea what is going on? The cable or speedo one makes a little click while it is jumping. It echoes so I can't determine which.
Josh

72 F-100 Ranger XLT SWB
71 F-100 Custom SWB
67 F-350 Dually Dump
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re: Crazy speedo problem

Post by heep70 »

The cable housing might be gummed up inside or the cable itself might have a fray.
Greg

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Joshpow
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re: Crazy speedo problem

Post by Joshpow »

Can the gummed housing be fixed? I know tha cable fray would require a whole new cable.
Josh

72 F-100 Ranger XLT SWB
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67 F-350 Dually Dump
02 F-250 Stroke
http://www.cardomain.com/ride/2972100
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Post by FLATBEDFORD »

After messing with my speedo for a different problem. http://www.fordification.com/forum/view ... hp?t=35428
I'd say it's a cable problem. There are no major moving parts on the dial itself. Not even a gear or anything. It's a spinning magnet that makes the needle move. The cable may be gummed up or fraying causing it to bind at different speeds, but not all speeds.
Steve

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Joshpow
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re: Crazy speedo problem

Post by Joshpow »

Is there hope of dleaning a gummed cable?
Josh

72 F-100 Ranger XLT SWB
71 F-100 Custom SWB
67 F-350 Dually Dump
02 F-250 Stroke
http://www.cardomain.com/ride/2972100
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re: Crazy speedo problem

Post by heep70 »

Spray some brake cleaner into the housing and spin the cable with a drill motor. Maybe some graphite when all is done and the brake cleaner has evaporated out of the sleeve.
Greg

1971 F250 "Highboy". SOLD to "Highboy_Firefighter_71"
2000 Subaru Outback limited.
2000 F250 4X4 PSD SuperDuty Crew.
2010 Polaris 800RMK Dragon 155"
2013 Polaris Pro 800 RMK 163"
1980 Built Toyota "Trail Rig".
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Joshpow
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re: Crazy speedo problem

Post by Joshpow »

Sounds good. Can I pull the cable out of the housing without removing the gear in the transmission? Also, Just graphite like you use in a lock? Thanks for the help guys.
Josh

72 F-100 Ranger XLT SWB
71 F-100 Custom SWB
67 F-350 Dually Dump
02 F-250 Stroke
http://www.cardomain.com/ride/2972100
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re: Crazy speedo problem

Post by SteveC »

yea lock grafite used it in my speedo cable housing and it helped the bouncing some. Mine bounce 0-40 then stabled out ... made getting tickets realll easy
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Re: Crazy speedo problem

Post by NM5K »

Can also be the speedo gears on the tranny.. That's why mine acts funky...
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Re: Crazy speedo problem

Post by Jake11 »

How to. Disconnect at speedo. Pull out cable. Clean it with a rag & solvent. Coat with motor oil and put it back in
housing. twist and work it in & out. Pull it out and wipe it again. Recoat with oil and install. Wipe oil off of last 5"
so it don't get in speedo head. If that don't fixee, time for new cable. 8)
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Re: Crazy speedo problem

Post by Joshpow »

FIXED! Crazy goof who routed the cable had let it hit the exhaust sometime in the past. The housing was ruined! I had to get a new cable. Pulled the cable out before I noticed it. Wouldn't go back, thus problem found upon investigating why. Fixed now with smooth as silk operation. THANKS GUYS!!!!!!!!!! :fr:
Josh

72 F-100 Ranger XLT SWB
71 F-100 Custom SWB
67 F-350 Dually Dump
02 F-250 Stroke
http://www.cardomain.com/ride/2972100
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