My speedometer has always been cranky. Between the needle bouncing or not moving at all, to showing speeds that seem way off when it does actually work a little. After a 20+ mile drive yesterday with the needle stuck at 30 I figured it was time to take the speedometer out of the cluster and give it a once over.

Now that I have it out, I can see that it needs a good lubricating. So I smeared the entire thing with white lithium grease. I used the same stuff to lubricate the new speedometer cable too. That should stop the bouncing. As to it being stuck, I tapped on the housing and some grit came out. It then returned to zero. Maybe it'll actually be functional now.

However...

Here's where I need everyone's help. The needle doesn't seem to be aligned evenly with the triangle at the base. Could anyone take a look at there's and tell me if this is the way it's supposed to be? Or does it need to be straight? If it does need to be straight that may explain why it seems my top speed, according to the speedo, is 15 mph.

Also, what's the little hole for on the outside of the housing. It doesn't seem like it's open to anything.

See below.

 

Hi Calvin,

yes the needle should come straight out of the triangular section:

 

Yes, that hole is a weep hole for a few drops of oil. but since it hasn't been oiled for so many years I would lube the entire thing really well. Put drops of a light oil onto the little gears and worm drive. I have used WD40 in the past with no ill effects, however some would argue against using WD40. I wold lube it until you can turn the little brass end freely and therefore move the needle freely and easily.

about the needle whether bent or straight, I am not going to say for sure. I think it should be straight but I am not sure. I can check it on a 53-55 speedo I have among my parts....

 

As for that liitle hole: isn't there a liitle screw in that hole?

 

Notice how Rico's needle is different than Calvin's.

Now would be a good time to put some red/orange paint on your needles Calvin, if they need it.

 

Mine is a reproduction, but the old one had a straight needle as well...

 

Needle straightened. I just airbrushed the needle with a nice "metallic stop-light red" Testors model oil paint. I'll go back over the stem with a flat black when the red dries.

Yes it seems like a small allen-head screw might be in that weep hole but it's got crud in it and I can't quite say for certainly. I'm trying to pick it out but if it's just a hole I don't want to force anything into the drive spline. Hmm.

 

All done. Looks good to me. I'm leaving the back plate alone. Sure it's a little old looking. But it's original and I like it that way.

If anyone knows for sure if there's a small screw to access the back lubricating weep hole I'd appreciate the feedback. Like I said I just don't want to push any crud in there if it's just a "hole."

 

Looks good Calvin. So you airbrushed it? I just used a very small brush. about the face or the back plate.... I don't know how you could clean that up or paint it with out disturbing the mph hash marks.

About the weep hole, there should not be any screw in there. Just keep picking out the 61 years of dirt!

 

Yes, I have a Badger Patriot 105 airbrush and just about every color of Tamiya acrylic and Testors oil model paints for my diecast models. It worked well for this. I thought about shading the areas of black around the tick marks to clean up the back plate but then it won't look uniformed. My old truck isn't perfect anyway. I'll just add it to the list of "dirty, bruised, dented, cracked."

 

I know everyone has their favorite whatevers but I'm gonna be a pita and say I have no idea what white lithium is good for. It collects dirt like crazy and turns into waxy crud (technical term) that doesn't flow. If a lubricant doesn't flow it soon leaves the part un-lubricated. Speedo cables best lubed with something like a light wheel bearing grease, just a smear of it along the length of the cable. Too much and the cable will act like an auger and pull the grease to the end and drip the oil onto your pants leg. Regarding WD40 - I have no problem with WD, use it most every day. But I consider it a solvent and not a lubricant. 3 in One is a lubricant and won't turn into gum for quite a while. Plus a speedo only needs 2-3 drops (some had a wick) any more than that and you'll be collecting dirt, fuzz, etc. Nice thing about 3 in One is you can apply a few drips where needed whereas WD and its companions are sprays that are hard to keep in one small spot. Another good oil for the speedo would come from that little plastic bottle Harbor Freight includes with its air tools.

 

That was my exact sentiments when I replaced my '56 speedometer with another original part that worked. Oddly enough, the needle looked almost new except for a scratch. But my backing plate looks a lot like yours.

(My original backing plate looked brand new. )

 

I was lucky, I guess, with my instrument panel. My truck was rusty inside and out, but the face of my speedo was in great shape. All I had to do to the speedo and other gauges was to clean them up, paint the needles, and lube the speedo. I did change out the odometer because mine didn't work. I did wipe down the black painted surfaces with a rag wetted with Armour All to shine it up. I did sand and paint the the bezel as it was rusted.

 

They really don't build 'em like they used to. I wonder how many parts on modern cars wil still work in 60 years of dust, rust, heat, etc.

 

I had to replace my speedometer (backplate, needle an mechanic) since the original one didn't work anymore. But of course I kept the old one an I'll try to reanimate it during the next winter (although I'm not a Swiss clock maker).
I just noticed that the needle gets stuck when driving more than 50 mph.
It seems there's a little dent in the front plate where the needle touches.
So I'll need to retrieve and open the unit again and fix this. Will keeping me practising