The Stovebolt Site Forums The Shop Area Driveline It Rattles and Spins Wildly

A 1949 Chevy panel truck, that is the speedometer cable has a loud spinning noise and it makes the speedometer needle to go all over the place when above 30 mph. It's a new cable and the correct one for the truck so why does it do this? More important is how can I get it to stop doing this, could it be that the speedometer heard need to be removed and cleaned and oiled, please give me your insight. Thank you.

God bless,

Dave

yes, it's the speedo that's the noisey problem, not the cable

Bill

If you pull the speedo and pull the head out of the housing you will see a very small cupped soft plug. The plug is even with the mounting area, SEE PICTURE
Under the plug is a felt wick. If you put a few drops of light oil on the wick you will most likely stop the noise.

Dave:


Thank you, I greatly appreciate it.


God bless,

Dave

Dave:

Would a lack of lubrication also explain why the needle swings wildly back and forth at speeds above 30 mph, the cold also seems to make it worse. Again, thanks.

God bless,

Dave

Light binding in the speedo head causes the cable to wind up then release causing the needle to bounce.

David:

Thank you, I greatly appreciate your insight.

Dave

Dave;

How do you get that plug out? I wouldn't want to destroy it trying to pry it out of there. My speedo is starting to bounce a little bit. I'd like to get on top of it before it gets out of control.

I use a small screwdriver with sharp corners and pry it out.
If you happen to damage the plug I can help you out.

Dave;

Ok. Thanks.

I need to get myself a decent set of screwdrivers. Right now all I have is a couple of those all-in-one interchangeable tip screwdrivers. It's time I bought a real set of good screwdrivers. Its amazing how often I wish I had a real screwdriver to use.

If I jack up the plug, I'll PM you for help.

You don't have to pull the plug out though, correct? You just put the oil on top and it soaks into the wick?

Pre 68 Dave

Can't seem to get the plug out, and what can I do if it gets damaged? There also seems to be another cap on the side, does this also need to be pulled? Thanks.

Dave

Only the plug in the link above needs to come out.
I don't know if you want to send it to me but that would be OK.
If you damage the plug I have replacements.

I have a 1940 Chevy 1 ton with the same problem. I know the speedos have a different face but I'm wondering if this would fix the problem on my truck too?

It is worth a try.
Have you lubed the cable? It is the first thing to try.

I used a slight amount of light-weight oil on the cable to get it into the jacket but other than that very little oil was used; and as far as the actual speedo no oil was used. I don't recall a plug on the unit but maybe I could let it drip in.

I was thinking about you not being able to get the plug out. I think you could obtain the same results by soaking the threaded part in a small container of light oil. The oil will wick up the shaft to the felt and lube the shaft at the same time.

Dave:

"Light oil" would 30 wt. engine oil be ok?

Dave

I would prefer ATF but 30W may be OK if it is warm.

Dave

Thanks, I'll try the atf

Try using an old style (tweezer) fuse puller. Small pair of needle nose pliers,like on a swiss army knife?