1978 speedometer / odometer head unit

[johaner78]

Hey guys,
I've got the speedometer head unit out of my dash now. When I hook the speedometer cable up to the head unit and turn the cable with a drill, the speedometer needle is not real steady, it jumps all over the place. Anybody know what might be causing this? The cable has been disassembled and lubed with powdered graphite and turns real nice. The speedometer needle has been painted with Hipo Parts speedometer paint. When I spin the cable, the head unit does not sound real smooth - anything ever go wrong with these units? If so, any fixes other than getting a different head unit?

Thanks,
Eric

 

[cipsmithers]

Not helping yer post, but yer racking up some nonexistant miles doin that

 

[johaner78]

Chris - not worried about that. I'm making the odometer "like new" again - just like the rest of my crew. It's been totally rebuilt from the ground up - and i mean EVERYTHING. So the odemeter will reflect the actual miles on teh truck when I finally get it on the road. I just need some answers to why the needle bobs so much.

 

[LEB Ben]

Normally a bouncing needle is the result of a stripped speedo driven gear...beyond that I really don't have a clue.

 

[cipsmithers]

Chris - not worried about that. I'm making the odometer "like new" again - just like the rest of my crew. It's been totally rebuilt from the ground up - and i mean EVERYTHING. So the odemeter will reflect the actual miles on teh truck when I finally get it on the road. I just need some answers to why the needle bobs so much.

I know, just screwin around. I always figured i would do the same thing if I ever had the money to do a rebuild

 

[johaner78]

Ben, after further inspection, i believe there are some gear problems even tho they look ok. Might just have to find another head unit.

 

[Ranger429]

I got an 85MPH head with the blue high beam already zero'd out on my desk right now if your interested.