I'm rebuilding a 57 Chevy and the speedometer was locked up with hard lubricant. I dissembled the thing and got the rotator free. Now I need to know how to re-calibrate or if I need to? Any speedo experts here?
not sure what you mean by re calibrate it? you have to set the needle to zero. You have to get the spring tension right. It still won't be accurate at all speeds, from my experience. hopefully the bushing in there is tight? the one that goes between the two moving parts, it's a little tiny thing.
Like he said. It depends how far down you tore it. I just pull the sweg plug from the speedo shaft and ad lite oil. Run it with a drill both directions until it frees up. I zeroed a couple but is wasa time consuming job. Really don't remember how I did it.
I pulled it all the way down to just the rotator magnet and the back housing. Got it freed up and would like it to be semi accurate. I zeroed it too, very easy to do when it is out and in your hand.
put it in the car, see how it does, compared to a gps. Also check the gearing by comparing the odometer to highway mile markers or something. be sure to check the speedo at different speeds...sometimes they are good at lower speeds, but don't move far enough at higher speeds, etc.
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