Odometer problem...please help
Thread Starter
Instructor
Joined: Sep 2001
Posts: 129
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From: North Central TENNESSEE
Odometer problem...please help
I have a strange problem on a 67 small block 327. The odometer registers about 2 miles for ever mile I drive, both on the speedometer and the trip meter. The car had a 4:11 rear end and a 4 spd M-21. The speed registers correctly. Can anyone please help me?
Thanks,
Alex :chevy
Thanks,
Alex :chevy
Le Mans Master
Joined: Nov 2000
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From: Going too fast over the hill. Iowa
Re: Odometer problem...please help (Alex in Germany)
It's a gear drive, so I am puzzled. Any chance the car was prepared for sale in Europe with a kilometer read-out gear drive for the odometers? Did you import the car, or was it factory delivered to Europe?
Thread Starter
Instructor
Joined: Sep 2001
Posts: 129
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From: North Central TENNESSEE
Re: Odometer problem...please help (magicv8)
It's an American car brought over about 12 years ago. The speedo is in MPH. Driving at 60 for 1 minute registers just over 2 miles. In any case that isn't correct for Kilometers either. Any more ideas?
Alex :chevy
Alex :chevy
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From: If I say it's safe to surf this beach ......then it's safe to surf this beach
Re: Odometer problem...please help (Alex in Germany)
It would be helpful to have a little history such as......it's been doing this regularly for the past 5yrs., or it just started doing this 2 days ago after working fine for 5yrs, etc.
I don't know if I can help you that much but I've got an idea of what's happening.......I'm thinking its about to break. I've had two odo's go out over the years. One just quit suddenly while I was driving, but the other started giving crazy, eratic readings all over the place before it finally quit altogether. But it was not a steady 2-for-1 reading like you're getting.
Also, you said the car had a 4:11......did you mean it has a 4:11, or has it in fact been changed to something else (not that it should make a difference on the odo).
I don't know if I can help you that much but I've got an idea of what's happening.......I'm thinking its about to break. I've had two odo's go out over the years. One just quit suddenly while I was driving, but the other started giving crazy, eratic readings all over the place before it finally quit altogether. But it was not a steady 2-for-1 reading like you're getting.
Also, you said the car had a 4:11......did you mean it has a 4:11, or has it in fact been changed to something else (not that it should make a difference on the odo).
Le Mans Master
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From: Going too fast over the hill. Iowa
Re: Odometer problem...please help (Alex in Germany)
My guess is that it needs to be cleaned and (very lightly) lubricated. I have not had mine apart for cleaning in more than ten years. If the speedometer is accurate - wait until the next time you feel like pulling the instrument cluster, clean it and lubricate it with a touch of very light machine oil.
BUT FIRST, TRY THIS - disconnect the trip odometer reset cable from the back of the odometer, and see if that has any effect on the problem.
BUT FIRST, TRY THIS - disconnect the trip odometer reset cable from the back of the odometer, and see if that has any effect on the problem.
Burning Brakes
Joined: Nov 2000
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From: da up
Re: Odometer problem...please help (Alex in Germany)
Weird, The odometer is gear driven off the input of the speedo head.
So it cannot increase by itself.
Maybe the speedometer is actually reading slow and someone at one time corrected this by changing the driven-drive gears in the trans.
(a defective speedo could read slow but this would not affect the odometer)
This spring I fixed the odometer on the '64. was a stripped gear
I was just going to swap speedos with a spare I had. But when I tested my extra by driving it with a drill it read 30mph while my original read 55. so I swapped the gear out of it.
rod
So it cannot increase by itself.
Maybe the speedometer is actually reading slow and someone at one time corrected this by changing the driven-drive gears in the trans.
(a defective speedo could read slow but this would not affect the odometer)
This spring I fixed the odometer on the '64. was a stripped gear
I was just going to swap speedos with a spare I had. But when I tested my extra by driving it with a drill it read 30mph while my original read 55. so I swapped the gear out of it.
rod
Le Mans Master
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From: Going too fast over the hill. Iowa
Re: Odometer problem...please help (yooperod)
yooper - great thought
Alex - here is the list of speedo gears that apply to rear end ratios:
ratio__tire size___drive gr_____driven gr_teeth_color
2.73__8.15-G70__3895494____3987918_18____brown
3.31__8.45-G70__3924098____3987919_19____natural
3.36__8.15-G70__3924098____3987920_20____blue
3.55__8.15-G70__3924098____3860344_21____red
3.70__8.15-G70__3924097____3860345_22____green
3.70__8.45-____ 3924098____3860344_21____red
3.73__8.15-G70__3924097____3860345_22____green
3.73__F70______ 3924097____3860348_25____orange
4.10__8.15-G70__3924097____3860347_24____yellow
4.11__F70______ 3924097____3860348_25____orange
4.56__8.15-G70__3924097____3860345_22____green*** uses 3890575 adapter
[Modified by magicv8, 9:03 PM 7/1/2002]
Alex - here is the list of speedo gears that apply to rear end ratios:
ratio__tire size___drive gr_____driven gr_teeth_color
2.73__8.15-G70__3895494____3987918_18____brown
3.31__8.45-G70__3924098____3987919_19____natural
3.36__8.15-G70__3924098____3987920_20____blue
3.55__8.15-G70__3924098____3860344_21____red
3.70__8.15-G70__3924097____3860345_22____green
3.70__8.45-____ 3924098____3860344_21____red
3.73__8.15-G70__3924097____3860345_22____green
3.73__F70______ 3924097____3860348_25____orange
4.10__8.15-G70__3924097____3860347_24____yellow
4.11__F70______ 3924097____3860348_25____orange
4.56__8.15-G70__3924097____3860345_22____green*** uses 3890575 adapter
[Modified by magicv8, 9:03 PM 7/1/2002]
