Speedo service?

My speedometer started making a howling/whining sound the other day, and the needle started bouncing around. Can I open it up and grease it? I wanted to ask before I just tore into it.

 

Speedometer service is pretty delicate ... I would not do much to the speedo head beyond some gentle cleaning with gentle air or a Q-tip and a tiny bit of oil on the jewels. The mechanism is more like a clock than anything.

More often problems come from the speedometer cable, not the speedo head. Make sure the cable routing is good, with not sharp bends. You can take the core out of the cable and clean and lubricate it. We have covered this in detail in earlier threads if you search. Use Google - "site:earlycj5.net <your search terms>".

 

There is also a tiny external oil hole on the back-side of the speedo, just above where the cable attaches.

You have to stand on your head behind the dash to find it.

 

Thanks for the tips! I unhooked the cable, and the growling stopped on my way home. Lubing the cable is an easy task, I will try that first.

 

Speaking of cable routing, my old speedo cable broke right where it enters the transfer case. Since the case is so close to the frame, the cable has to make a rather sharp bend. Any thoughts on this or how to avoid it?

 

My cable has a big spring around it that keeps it from bending too sharp.

 

Can't help with the sharp bend, but generally ... anywhere there is a change in stiffness of a stressed material there will be a stress riser. So the point where the cable goes into the transfer case is the most likely breaking point. You could make a standoff that supports the cable somewhere up from the connection. This would reduce the stress on the connection and make breakage less likely.

 

Just in case you or anyone else need one repaired - http://www.deluxespeedometer.com/

 

Interesting...have a source for this cable?

 

Stewart Warner used to make a 90* coupler for this purpose. Don't know if any are still out there. Installed many of them years ago.

 

I just use a heavy piece of slit fuel line over the bend at the transfer case, secured with wire ties. It has worked for decades and keeps it from rubbing directly on the boxed frame.

 

I went to a local shop that stocks the speedo cable on a roll. You take the old one in so they know what length and what ends you need. I had them make it a bit longer so I could have gentle bends.

On a side note. If you remove the tcase brake drum (mine was inop) it's much easier to access the speedo cable connection.

Another note. I put an o-ring on the tcase end to keep the oil from leaking out.

 

I ordered the stock replacement for my 71. I'll make the turn where it enters the T-case as large as possible and hope for the best

 

I got around to taking out the cable today. There was very little grease on the cable and what was there was dried out and tacky. I lubed it up good and it stopped the growling. :tea: