Is it possible to lubricate the speedometer head?

oldbike99

oldbike99

Senior Member
I have a 1931 Model A with a noisy speedometer head. It functions fine and the noise comes from the head, not the cable. Is it possible to lubricate it or is this a job best left for professionals?
 
In the Stewart Warner round speedo they have two brass covers on the side. Under the covers are 2 felt wicks. They are both likely very very dry.

There is an addtional problem. The potmetal frame can swell causing the bushings to get tighter on the shaft.

There are other round speedos and I believe they all have pot metal guts. Most can come apart without much effort and be lubricated. There is one (Northeast?) that is probably harder then the others to get apart and back together. I happened to come across a very nice SW with good numbers so that is the one I rebuilt.
 
As a professional, I will state that I would recommend having your speedometer serviced by a shop. The cost vs benefit is in your favor. You should have an accessible oil wick on the rear of the speedometer, but I don't have one in front of me. Standard 3 in 1 household oil will work if used sparingly. It helps to work some into the magnet shaft collar gap also. A professional shop will completely disassemble, clean, inspect, adjust, lubricate and calibrate back to factory spec. Usually that level of service runs in the ballpark of $150, to give you an idea.

www.morrisgauge.com
 
Do as morrisgauge says. If a speedo is taken apart it usually needs to have the magnet re-calibrated. As a temporary measure you could soak the drive-end of the speedo in oil, just the end. Leave it in a can overnight in order to let oil seep up into the shaft. Too much oil is not good.
 
I just took my speedo apart and removed/cleaned all the old grease, dry mud really, out of it, and re-lube (white lithium) and re-assembled, i treated it like surgery and was very careful and precise, the numbers and dial are good with a nice soft yellow antique look that I think I'll keep, have not had a chance to test it out yet, what with all the rain and mud out here. But it works great hooked up to a drill.
As far as a wick, I never did see one, if someone has a pic of a wick that would help, maybe mines missing, I'm not an expert so I don't know.
I have a '31 round, and nothing about a wick in the Les Andrews book.
 
The pot metal around the magnet shaft, in my Stewart Warner, was SO TIGHT! I drilled several 1/16" holes & injected some 2-cycle oil in them, with a syringe. Finally got it turning a bit, with a stub speedo cable, turned it SLOWLY, CCW, with a drill. Oiled it 2 more times, laid it in the sun for 3 days & rotated its' position several times. It freed up fairly well & hopefully it won't TWEEK my new cable.
I once knew a speedo repairman & he shared lots of "secrets" with me, even how to ERASE 67,000 miles, in 3 1/2 MINUTES!!
Bill W.
 
I often find that the speedometers that have set for a few decades that are tight on the magnet shaft are also the ones with hard grease in the odometer assys. They usually fail when trying to turn over the next 1000 or 10000 mile digit, that makes the little gear on the end turn 4 or 5 rows of wheels all at once. It is more than the little pot metal guy can handle. After 80+ years, the speedometer should be serviced before it fails, it is cheaper and easier.

www.marksspeedometer.com
 
The wicks on the SW round are located on the side opposite the shaft that drives the odometer. You need to pry off 2 brass covers and pull the felts out of the holes. The end at the shaft will be loaded with a hardened lubricant. You need to work some solvent in to get the old hard stuff out. Then soak in in oil and put them back in place after you have the main shaft spinning fairly free. If the mainshaft does not spin free by itself then you can expect the speed read to bounce. One I had the pot metal was going bad causing the shaft to not spin free even after trying to wear it free with a drill. The others I had came up spinning good with a cleaning and lube.

The odometer likely needs to have the old lube cleared out and new worked in place. Do not try any harsh cleaners as they will quickly remove the number. I used some fine watch oil and then worked the numbers by hand till I got the thousands and ten thousands rolling nice. Taking the wheel apart would be best, but if you have real nice paint you want to think twice. My experimenting makes me believe you can not easily get wheels off without hurting the paint.

Of course you will need to calibrate the speedo. The magnets are likely weaker and you will need to move the shunt on the wheel. You kind of need to make a calibrated rpm gauge. I made one and posted some ideas here a while back.

The above is based on my limited experience. Quite frankly, it is likely cost effective to have someone rebuild yours if they are doing the numbers and calibrating.
 
Well, I just waded right in and removed the dash and Waltham speedometer. A little careful prying and the bezel came off. A single screw on the backside allowed the mechanism to be removed from the housing. A few drops of three-in-one oil on all the pivot parts and back together it went. About 1 hour and all noise is gone!
 
When my dad and I installed a new speedometer cable on our '31 Deluxe Coupe, the speedometer whined like a banshee. I put up with it for a couple of months until it just became unbearable. Yesterday I pulled the speedometer (a Northern) out and pull off the casing. It was pretty clean inside with no caked grease or grime. There isn't much info on the Northerns around here so I just winged it. I used a syringe to lube a couple of key locations but I never saw any felt pads or other obvious lube spots.

The speedometer went back together fairly easy and there was no issue with loose parts. The whole thing went right back together. Took it out for a spin and the noise is completely gone. I don't know how long it will last but, I'm ready to do it again, if necessary. I tried it because I figured the worse that could happen would be I'd screw it up and I'd have to buy a refurb unit anyway.

So, if you are considering it, go ahead. It's worth the effort.

Regards,
 
So many posts on this I didn't know where to post this! Found 2 little tricks that might help people out. On a 28-29 cable there is room in the housing which makes the cable slap around. I got 1/4" od polyethylene tubing, you can get it at home depot, it's for refrigerator waterlines. Cut it to length, from ferrule to ferrule on cable. Slice it lengthwise and lube cable anyway you wish. I use Vaseline mixed with graphite powder. Put cable in this sheath and slide it into housing, it will fit. Quiets it down a lot. Also, at the speedo drive end at ******, place two felt anti rattle felts from the control rods over the keyed shaft that goes into housing. They fit perfect. Keeps grease from migrating up the cable. Universal ball should not be over greased.
 
Hay I get $150.00 to total rebuild them. That gose for the All the S/W, Waltham, and North East. jrnichols642@yahoo.com
 
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