speedometer problem

This happened to me on my 69 bug about 12 yrs ago. Was driving on some backroads between Chico and Sacramento in my college days. The noise got to be such a pain in the butt that I eventually stopped, opened the front, and disconnected the speedo.

My solution: Few months later, someone abandoned a year-compatible bug in front of my apt complex. Parts is parts, got me a new-to-me speedo out of it early one morning. :-)

Course, this was back when you could find abandoned cars and strip any parts off em before the wrecker would come and get them.

-Rob

Patrick Glenn wrote:

There is a brass bushing at the "inlet" to the speedo. The internal drive shaft rides in the bushing. When it finally loses all lube, it squeals like a stuck pig.

You can probably squirt some very light lube in there without taking the thing out although it is at an odd angle.

Speedy Jim

Ditto what Jim said. I had the identical problem with my '69 and a quick spray of silicone lube cleared it right up.

Patrick Glenn wrote:

Dis-connect the speedo cable before you drive again. The speedo needs lubrication. If you don't disconnect the cable, you'll break the cable. Although it's only a few $$, and really easy to replace.

Remove and re-build the speedo. This is really easy. Remove the negative connection to the battery, as you'll be makin some arc-n-spark if you don't. Get some paper and masking tape, and mark the wires. Then pull them all off, being able to replace them to the correct location. Unscrew the two phillips screws, not all the way, just to losen the retaining tabs. Turn the speedo about 1/8'th of a turn. Pull it back, and work it out.

WARNING --- DO NOT EVER REMOVE THE SPEEDO NEEDLE! YOU NEVER NEVER NEED TO DO THIS, AND IF YOU DO, YOU WILL NEVER GET IT BACK ON CORRECTLY! ---

In a nice warm and dry area with a good clean bench. Lay a thick rag, or towel down. Place the speedo face down. With two really small sharp flat blade screw drivers, carefully pry open the rolled lip on the back side (of the speedo) crome ring. This is the only thing that holds the speedo together. When you get it open, write down the order of the glass, and gaskets. Remove the screws on the back of the speedo. The speed needle is driven by a spinning disk shaped magnet. The needle rides on a steel bell, and is pulled to 0 by a spring. The faster the disk turns, the more pull on the bell, the more needle deflection. The needle is calibrated by the strength of the magnet disk, the distance from the disk to the bell, and the weight of the needle. When you remove the steel disk, there are two grooves on its shaft for setting the distance to the bell, There is a clip that rides on one of the grooves. Make sure you know which one it came from. Else your speedo will be way wrong (how do you think I know this). The problem is likely in the shaft of the disk. Remove and clean well, I used moly grease. Take out the gear section. Clean and re-grease the gears. Re-assemble, and re-install. Don't get sloppy with the grease, or you'll have it smeared on the inside of the speedo. If you clean the glass, use a cloth, as paper will leave lint which you will see after re-installation. Now is a good time to replace the colored lenses over the lamps. Also it's easy to replace the lamps now too.

I used a bead of plumbers putty for stainless steel to re-bed the speedo.

Don't use WD-40! It melts grease. Been there.. snapped a speedo cable cause it froze. Use white lithium grease or similar.

If hosing down the line with silicone lubricant doesn't help and you end up dismantling the speedo like Patrick suggested, dunno if it'll help you but here's a mess of snapshots I took when dealing with this exact same problem on my bug:

Basically after 37-odd years of use, the grease had stopped greasing and all the little bits inside were rubbing, turning your entire dash into a sounding board. ;) Nothing more jarring than being on a 3 hour road trip, 8 miles from the next exit, and having your speedometer attempt it's best banshee impersonation.

I should note that at a later dissasembly of my speedo, I broke those little twist tabs that hold the whole assembly together. In the page I linked above, the tabs I'm talking about are in the 3rd shot. Not sure if later model speedos used screws internally to prevent this, so depending on the year of your car, ymmv.

What I did to fix this was take my dremel and drilled out the "dots" that serve as guides to align the grey metal piece with the speedo/odometer assembly.

I then found a couple tiny screws that would fit in the holes and just bolted the two halves together.

Uh, well, I already sprayed some WD-40 on there yesterday, and at least it did make the noise go away... I disconnetced the cable and sprayed the cable connector and the speedo connector. Maybe I should go back, wipe both connectors down, and use grease as suggested?

Patrick