The Stovebolt Site Forums The Shop Area Interiors '51 speedo needle removal

Stovebolt Nation Yest I pulled my guages on my '51 3/4T 6V with '62 235 motor

While pulling the crumbly needle off the speedo, I pulled straight out and I think I broke the 1.5" long pin that comes out of the gear/spring set up at the back of the gauge, the pin is about 1/2" long and broke off where it goes thru the holder, (see photos). (reading past threads, I now see to pull back while holding the pin with angled needle nose and giving the needle a slight counterclockwise wise twist. I now wish I had, but the decal folks said pull straight out. My bad. Any thoughts ? Options are Palo Alto Speedo and I'm in the area, but I'll bet they will be more than a new speedo from Truck Shop in Orange Calif, or Jim Carter etc.. (about $125).

Any thoughts? or good fixes/saves....

Clem

You didn't necessarily screw up. The needle shaft is a bit fragile. I broke mine the same way. I wound up buying a remanned speedo when I was at Jim Carter a couple years back. And IIRC it was more than $125. I would check with your local shop and maybe they can just replace the cup and shaft for you if everything else is in decent shape. Or it might be better to get the whole thing redone. Jim Carter supposedly does theirs in-house, but local shop should be just as good.

That happens frequently, Clem. That shaft is thin and even a tiny bit of sideways movement will snap it. The truth is it can be replaced but only if you were fortunate enough to have left the same size stub sticking up on the other side. The bad news is I should tell you that almost never happens. Carefully unscrew the two screws holding on the front plate and let us see a digital image of what you have left to work with there. If you have even a bit of stub which is the same diameter, you can get a piece of brass tubing and use it to make a collar which can be either epoxied or soldered on...depending entirely on your skill level. I have one of these sitting in a box which I've not repaired because it is going to require disassembly and some machining. Maybe I ought to get it out and take a look. I'll do that this evening. First let's see what you have. Please be careful with those two screws. They might not want to release easily. The good news? It is just a speedo needle shaft and there are ways around it, I'm sure.

Jon, It looks like Clem has enough shaft still on the needle to do the tubing splice thing you're talking about. Just needs to get the stub off the needle.

Unfortunately, mine broke basically flush with the back of the needle. I suppose I could JB weld a new needle on the shaft if I wanted to reuse that speedo, but it's not in the plan.

I can't tell from his pictures, Kevin, however I think I have potentially good news for both of you. Especially if you saved the piece you broke off and maybe even if you didn't. More to follow once I finish some work here...

Getting the stub off the needle collar may not be too tricky.

getting the x-bar wasnt bad, I measured the rod and it's 1/16" below the rod and 1/32" thru the x-member and to the little cap at the top just behind the needle.

I have a friend that has a machine shop, so I could make a small sleeve that is drilled on both sides, one side 1/16" and then 1/32" up thru the bar, and thru the small brass bushing. One issue is the small cap at the end, that slides into the needle. Does this come off. Or I can drill out the cross bar 1/16, and sleeve it above the bar.

Ideas? Clem

Hi Clem (and others). Sorry I didn't get back to this last night. Sometimes things come up that aren't expected, you know. If you have a friend who is capable of machining very small parts, then yes...he could make a collar/shaft that would probably work. I should add I started learning watchmaking in late 1957/58, and I should also say some of this work isn't as easy as it seems it ought to be. But now for something completely different: The shaft where it passes through the little bushing is 1mm in diameter. Mine was an exact 1mm, actually and then it has a step-down to .83mm where it enters the collar. And so I came to what I believe may be an easier solution. Before I go any further, I'll point out where this mechanism should be oiled...because that's likely to be needed. What oil? Please look at image 1 below. That is a jar into which a can of WD-40 was poured. The can was knocked over and the spray nipple was broken off, so I turned it upside down and opened it with a beer can opener. If you pour WD-40 into a jar and leave it, the stuff will separate into 2 distinct layers (as you see). The top layer will be a fine light oil and the bottom layer will be paraffin and all sorts of other junk. Now you can appreciate why you should shake the can really well before spraying it. Back to lubrication, there will be a small brass plug which can be loosened with the edge of a blade (image 2 and 3). Oil this until it pools and then let it settle. Replace plug. The rear shaft collar (image 4) and the little shaft collar you see in image 5. Also put some light grease (like corn head grease or similar) on the worm gear that runs the odometer wheels. On to next post...

Well, ok...the little shaft collar is in image 4 above and the worm gear is visible in image 5. Also in image 5 you see where the shaft in this one broke. And now for the good news. The shaft coming out from the speedometer is larger than the shaft going through the bushing on the front plate. At 1.6mm the OD of it corresponds with the ID of 3/32" brass tubing sold by K & S and available at any hardware store. And another bit of interesting news is the OD of 3/32" corresponds with the OD of the collar to which the speedometer needle affair fits. Just like New York as we used to say. So get some of that size tubing and cut off about 1/4". Doesn't have to be exact, but you shouldn't need more than that. You can cut this small tubing with a box cutter blade as shown in image 1 below. Use a tiny round file to clean up the cut. Make certain it slides on to the shaft coming out of the speedometer unit. Now using cardstock make a little V to keep safe from shavings and with a Dremel tool, cut off 1/4 or so of the shaft as you see I've done below in image 2. Now cut a piece of the 3/32" OD brass tube to match (or a hair longer than) the length of the collar which protrudes and forms the spot for the needle to mount. And cut a bit of 1/16" tubing (maybe an inch). This will become our shaft in a moment. Carefully solder the 3/32" small piece you cut to the end of this 1/16" tubing, soldering only the end. We don't want it running back to the rear of this piece. In the third image below you can see the piece I've made in comparison to the original (broken) piece. I've done the soldering at this point. Now using a common pin vise and a 1/16" drill bit, open the 1mm hole in the bushing of the front plate carefully. Please do this by hand and don't use a power drill of any sort. Make certain your hole and the OD of the 1/16" brass tubing (which will be your shaft) are compatible. You may have to use a tiny rat-tail file to open the bushing hole just a wee bit. Now slide the part you've made into the front piece and set it in place to determine how much needs to be trimmed off the rear to make it just touch the shaft you cut off with the Dremel tool. Cut this to the proper length and slightly chamfer the end. Now using a pair of diagonal cutters or needle nosed pliers close the shaft of the connector piece you made (the 1/4" long piece) ever so slightly so that the 1/16" brass tube fits sort of tightly in there and slide it on so that it goes 1/2 the way in or so. You can set up everything to be certain all is well as you see I've done in the fourth image below. When you're certain all fits to your satisfaction, and the shaft moves easily when the speedometer rear piece is turned (counterclockwise, of course), then remove carefully and put a small dot of solder to hold the front part of the connector to the shaft you've made. Dress with a small file if needed and then re-assemble the front plate on and apply a small dot of solder to the rear part of the connector. Test the movement of the speedometer again. It should spin freely and move the needle hub nicely. In the fifth image below you can see where I've done that. You also see the odometer wheels have been removed. I'll make new decals for these and refinish them later. The decals you buy from the dealers of pickup parts should not be used, by the way. I'll try to remember to post that work when I get to it. For now, you're all done with your broken speedometer and you have some brass tubing left for other projects.

Added comment...I just noticed one of the front needle hubs I have is slightly smaller on the ID than the other, so it might be a good idea to check this on yours. (could be from different years, possibly) You can file the front piece you've made carefully to reduce the diameter if needed or you can use sandpaper. Brass fortunately allows you to do this easily.

Fellow I know asks what is a pin vise? Could be 2 styles. One uses a screw down collar and an internal collet split 4, 6 or 8 ways. Another uses a fixed collet with 2 jaws and a sliding ring to tighten things. These are used commonly by watchmakers, jewelers, electronics folks when it is necessary to drill a precision hole by hand. Very handy and not expensive. Image below.

Jon G, wow and wow... so much detail but all fully appreciated. I will go by our local hardware store or an Osh Supply in the area and try to look for these materials, thanks. If they dont have these, any good supply sites online to order them from? -Clem

You should put this in a tech tip and submit it to the Stovebolt editor.

Chris

If you don't find them, please let me know and I'll send what you need. My email address is [email protected]

Jon, Kevin and Chris and the rest of SB Nation. Thanks for your help

I got some tubing, and rod and want to fix this this week. Got some rebuild gauge stuff from Orange Garage in the LA area (rubber seals, needle for speedo etc...)

I want to ask you all best way to do the brass tube splice. My broken needle pin is at the transition from 1/16" to 1/32". The brass bushing in the cross rod is just above the break and it's 1/32" diameter. I see that I have two options to splice

A: Cut down lower on the 1/16" rod a little and splice there and run 1/32" up into the small brass cap that fits into the potmetal speedo needle holder. This will mean the spindle little rod will be changed from 3/16" long currently at the break site to about 1/2" long. And I will have to glue or solder in the tiny 1/32" rod into the 1/16" tube splice

B: Use only 1/16" rod and do the same splice site but only use 1/16". With this - will need to drill out the cross bar brass bushing to 1/16" and the small cap which also gets drilled out 1/16"

Hopefully look at my drawings and LMK which idea is better. I realized that if I splice above the cross bar, I can never take it apart again (hopefully never happen)

Also, the little tiny brass cap on the top, just under the needle. How do I get this off? Any ideas.
Last Question, solder or JB weld/equivalent? Need it to work, not be sexy also be able to come apart....
Real last question, any misgivings on redoing the odometer #s. I have stickers but scared they will peel off as my truck is outside and gets hot in the Calif sun, or just clean them up with simple green and call it quits. I have the stickers from the Redo Stickers Guage kit still

Thanks all.

Clem

Hi Clem,
The way I did this was to cut the shaft back where it was larger in diameter (back about 1/4" from where the unit I had was broken). You can see where I did that above. Then I joined the 3/32" OD and 1/16" OD pieces and soldered them carefully together, filing off the end nicely. And then I enlarged the hole in the speedometer bushing from 1mm diameter to 1/16" diameter. Then everything was joined as I showed above using a bit of solder with the 3/32" OD collar I had made. The 3/32" OD brass tubing fits almost perfectly over the shaft piece. I cut this shaft back to give myself room to work with the soldering gun without danger to anything. I used solder and only a small bit since doing it that way I could take it apart. The piece you see below is one I made after I fixed the speedometer here the other day. I didn't know what you might find or what you might do and thought you might need it. If you want it, contact me by email and tell me your postal address. [email protected]

As for the question about the decals (stickers, actually)...we get the same sort of sun you get and those stickers won't last very well at all. Again nothing against the sellers of those. But those were made for trucks that aren't used very often and spend lots of time in a pampered setting. And I hate to be a harbinger of doom, but the stickers you put on your gauge faces and speedometer may not last much better. But then again they might. Some people have said theirs did. I think it may be solely a matter of how the underlying surface was prepared.

I posted another note about the size of the tip of the unit I made. Turns out the hub part of the needle is larger than 3/32 by a hair in both cases, so at the worst you might need to use a dot of Plasti-Dip or glue or silicone...something to help hold it. All the shaft does is to move the speedometer needle around, so it doesn't need to be heavy duty as long as all is relatively secure. It isn't like a ceiling fan where the blades could come off and do some real damage. Good luck and let me know if you want the piece I've made.

Ah, sorry...saw your question about separating the hub from the remaining shaft piece. I just use a pair of needle-nosed pliers, grip the shaft and carefully pry the hub off with a small screwdriver...working first one side and then the other. About the speedometer needle hubs, they're all the same with GM...at least for a multi-year span. I've attached 3 images. Two are showing a hub I made for a new needle a few years ago. When you buy the new needles, you don't get the hub to which it attaches. A bit of aluminum, some brass tubing and JB Weld are all you need to make a new one. I made this one to fit over a 1/16" piece of brass tubing. I could also have made it to fit over a 3/32" piece of brass tubing (what was used to recreate the original end piece) by using 1/8" OD brass tubing, but at that time I was planning on using this on custom unit I was making. In one image you'll see where it fits over the 1/16" OD tubing. And in another image, you'll see a hub from some other GM product showing the inside diameter of the portion that fits over the shaft is 1mm. Hope this helps. Those hubs are pretty easy to make. The trick is remembering your geometry well enough to find the center of a circle...

And to answer another question you might have about image 1 and 2, I left the extending part long because I didn't know the distance to the face plate on the speedometer I was making...

Sort of closing the barn door after the horse bolts, but here's a sneaky trick to avoid breaking the next shaft that's worked for me in the past. Clamp a pair of surgical hemostats onto the shaft just below the needle, and use it as a fulcrum to pry the needle off. That avoids putting any stress on the shaft further down if you're careful how you pry the needle off.
Jerry

Thanks Joh and Jerry. The clamp would have done it. Sadly I have oogles of surgical hemostats.....

Good judgement is the result of experience and experience the result of bad judgement: Mark Twain a few years back.
Think of all the cool things I learned though

will mess with it this weekend and let you know whats up.
Clem

Stovebolters....

Sorry moving slowly on this, so many moving parts to a day..... but want this to come out cool and working.....

Got it apart (see photos), and ordered the pin drill, so will be good to drill. I'll sleeve below the cross bar and cut new brass rod the same size, drilling out with the pin drill the center bushing in the cross bar, but then when I get to the knurled little head, should I drill that out same size. and then solder all, being gingerly with the solder, and making sure the entire thing is the right length, and the needle sweeps flat across the dial in the speedo.

Thanks
Clem

Hey Jon and Crew New issue, speedo seems like it's slow on testing. See below

I re-stickered the left side 4 gauges and they look good, hopefully last ok

Using a hand drill I drilled out the cross arm brass bushing 1/16" easily, then I assembled it all and I re-soldered the pin on the speedo and that went well overall. I used a small pin with cap that Jon sent me (thank you !!), and soldered it together using just a dab of solder. It feels strong Prior to solder, I put the pin/cross arm together and then soldered. But it seemed to have some resistance to spinning comfortable. I got a very fine file and filed the solder off at the top of the sleeve at the repair.

With the speedo tranny end in my drill, I spin it and the speedo needle moves smoothly but max speed is only 26 mph as the drill is spinning 2500 RPM. I know a lot of cars have a top gear of 1:1 ratio, so that might mean 2500 rpm at the engine. But the odometer is spinning very fast, like i'm going 80 mph fast.

LMK your thoughts about why this is. Could be friction at the top brass bushing (I drilled and then filed the brass pin, maybe no smooth?), Or is there a problem with the drive at the btm. Not 100% clear how the spinning mechanism-driven by the square speedo drive, under the brass cup drives it, but there maybe an issue there. Or is there no problem and 2500 RPM should be 26 MPH and I've bumped my head and I'm overthinking it.

Any thoughts Stovebolt world? You all are helping me tons. !!

Clem

Gauges looking good! And nice work on the speedo needle shaft repair.

The cup on your speedo may need to be remagnetized. I think it takes a strong magnet (one of the new rare earth magnets to do it).

[on edit] I just noticed the fender you have the speedo sitting on. Your truck and mine could have been twins. Omaha Orange with a light blue paint job over the top.
Here's mine with it's original clothes on. Except for the hood, the pieces are primer grey now. PIC

My guess would be a magnetization issue. Here is a suggestion: if you have an old style computer drive, these contain some of the strongest magnets you'll find and should be strong enough for what you need. The key is taking them apart...you will need a small star driver. But lack of strong enough magnetization could be the answer. Also lack of lubrication could be part of the problem. Also...fyi...2500 rpm with a standard 4.11 rear end, 27 inch wheels, a 1:1 final gear should give you 49 mph almost on the nose.

2500 rpm should be 150 mph on the speedo
You can remagnetize it yourself easily
I posted how to do that a while ago and linked the exact magnets from Amazon that I used to do mine
You can’t overmagnetize, the iron posts should be saturated
-s

The Speedo is 1000 turns per mile
2500 turns is 2.5 miles
2.5 miles per minute is 150 mph
-s

Thanks Jon and Shop Shark

SS, I found your thread in 2018:
https://www.stovebolt.com/ubbthreads/ubbthreads.php/topics/1315306/1950-chev-truck-speedometer.html

and at amazon: now $15.39
https://www.amazon.com/Powerful-Neo...0+x+10+x+5&qid=1616446983&sr=8-2

I think I got this right, the spinning shaft, turns the magnet, which then spins the cup over it spinning it 180-270 degrees against the resistance of the spring. Then as everything slows down the needle returns to 0. So once magnets weaken, the cup doesnt spin so fast, and looks slow, 150mph then turns to 26 MPH. Strange that magnet 'strength doesn't change the speed of the cup around it.

Also, So I dont have to take it apart, or is it good to to put the magnets against the truck speedo magnet, as close as possible. I imagine this is best. Right?

I just ordered the magnets. Thanks SS !

Jon, I used your WD40 trick and lubed up everything. thanks! Will make sure that it spins easy also, no binding on the thin top x-bar bushing just under the needle.

Waiting on amazon now.
Clem

You have to put the magnet across the posts of the metal u shaped iron magnet
The cup has to be taken out of the way for this process

I stacked those Amazon magnets on top each other until I had effectively a bigger magnet that the N and S poles could bridge the iron U

Rubbed it on there a bit like they show you to do in school when magnetizing nails
But I also left it on overnight for good measure

-s

Thanks,

I imagine the right thing to do is let the magnets do all the thinking and to let them align the way they feel natural and just snap on, and thus make the magnetic fields natural and comfortable. They are so strong, I imagine that this is the only way to re-invigorate them and bring the iron in the magnets -bring them up to full strength

Clem

Put the Chinese Rare Earth Magnets on. Will leave overnite and thru tomorrow. The spinning magnets seemed pretty weak just now a zillion grades less than the R.E. Magnets.

Here is trying to realign the world, at least my speedo
Clem

I rotated the speedo magnet 90 and put about 4-5 across it through the middle
Reasoning is that it closed the flux circuit so I might get better saturation?
And I’m guaranteed not to accidentally make both poles the same polarity which may not drag the needle cup quite as well.

But you can’t really cause any permanent damage so your way will provide a good data point
I suspect it should work too because the field at the rare earth magnet surface is so strong anyway

Keep us posted
-s

Thanks SS for the heads up. will try this for next 24 hrs and give it a trail whirl tomorrow !!

Clem

Oh I mean sideways
The individual magnets have their poles on the larger flat face
I’ll try to draw a diagram
Brb (be right back)
-s

drawing attached
magnets bridge poles of speedo magnet
hope this helps
-s

Got it. Thanks SS Will flip them

Also will trial it all after magnet flip tonight and LUK how it turns out. Fingers crossed. I hate having to drive it at 150 MPH to get the speedo to move a little.

Clem

Hi, I also have a stuck speedo needle. 1951 Chev PU. Can anyone tell me if the needle shaft is supposed to be soldered to the plate that has the 5 odd spaced holes? There is a suspicious looking solder puddle on the
shaft where it enters the plate. Looks like it was soldered to the plate and broke loose. Maybe someone before me tried a fix? When spinning the cable entry piece, there was a lot of resistance. I pried the brass
cap off the 'oiler' hole, pulled out the matting plug and blew it all out with 80 lbs pressure from my steam cleaner. That really loosened it up!
Thank you for any help!!!

If there is any solder on the speedometer needle shaft, I would suspect somebody broke it at some point in time. The only way I've ever found to fix it properly is to do as I showed with a sliding sleeve and cut it back before it gets to the bushing. Good luck!