Speedometer Cleaning / Lubricating

[PVacco]

I'm in the process of cleaning my gauges and replacing the broken glass on the instrument panel on my 51 Coupe.

I've noted that my speedometer stops at about 6-8 mph when the car is stopped and typically is running about 5 mph light (registers approximately 5 mph more then actual speed) when I'm on the road.

In examining the unit it seems to have "thicken" grease or some other type of lubricant that is creating a little too much resistance for the needle spring. Any suggestions as to what to use to clean and lubricate this mechanism with?

I'm tempted to spray it with brake cleaner to remove the old lubricant and then give it a light oiling but I'm not sure this is the right way to go about it.

If anyone has done this before, I'd like to get your input.

Phil Vacco

[Lothar]

It sounds like someone may have used the wrong lubricant in your speedometer. I think you're correct to want to clean out the old crud, but I haven't done that, so I'm not sure quite how you'd go about it. Maybe it is as simple as squirting some solvent in there, but that could cause other problems. I would suggest you try something less agressive than brake cleaner to start, though. WD-40 or something like that.There is a small oil port at the top back of the speedo head. It usually has a perforated brass cap. You could try squiurting a little bit of WD-40 in there to see if it loosens things up.
The head should get a few drops of some light oil, like sewing machine oil. The cable should be removed and cleaned (Disconnect the battery before you do it! Don't ask how I know ). Then it needs graphite cable lubricant.

1950 Champion 4 Dr.
Holdrege NE

[warrlaw1]

I wonder if heat would change the viscosity of that crud? A hand held hair dryer might make that grease drip off. Haven't used mine since the mullet went out of style

[fmarshall]

The procedure that I have used is to remove the speedometer, use a match stick, coupled to a variable speed drill, to drive it slowly. The grease crud will slowly warm and all should get better with a little patience.

The best way is of course to tear the offending components apart and reassemble properly lubricated.

========================
63 Avanti R2, 4-Speed, 3.73 TT
Martinez, CA

[PVacco]

I want to thank you all for your input.

Yes the speedometer does have a perforated brass cap (found it once I used a tooth pick to remove the tar like black gunk that was covering it.) The stuff is very sticky and smears so I think its old dirty grease. Same stuff was on the end of the speedo cable as well.

I'll get some graphite lubricant and see what I can use as a de-greaser to improve the function of the speedo. There is a inner ring in the speedo that spins within a metal tube when the cable turns. This has a film of a black grease like substance on it and I think that this is what is preventing the speedo from resting at zero when it is held level (does to to zero if I turn the speedo 90 degrees to the right).

P.S. I did disconnect the battery cable before staring to disconnect the gauges.

Any additional advice is appreciated.

[s2dwagon]

Hey! When did the Mullet go out of style?

Scott

[PVacco]

For those of you interested. I was able to pry apart my instrument panel to get to the broken glass and replace it. (see yellow arrow) While I was there I cleaned and polished everything a bit (Couldn't do much with the gauge needles) and reassembled same. As for the speedometer, I did spray most of the crud out with brake cleaner and once it evaporated I applied some light 3 in 1 oil and WD-40. I did paint the speedometer needle and reset to zero by adjusting the retention clip that held the spring. Everything works find and my GPS unit says I'm just about dead on with the speed. Also replaced bulbs with Xeon bulbs. Much brighter.

[Johnnywiffer]

If you're "just about dead on" you're ahead of 99% of Stude people. Because most Stude speedos read about 10% fast from the factory. I think it's supposed to give you a feeling of superiority. [)]

Unfortunately, I think most odometers are also fast, 5%-10%, so you THINK you're also getting better mileage than you actually are.

By the way, that is a VERY clean-looking dash!

John

[Bullet]

How did you replace the broken glass? Did you buy another instrument cluster or have the glass cut? I have a 50 Champ with broken glass and am afraid that a glass cutter would not be able to cut what I need with that thin of glass. thoughts?

[5brown1]

Where did you get Xeon bulbs for the dash? I assumed you meant you used them to illuminate the gauges. Do they get hotter than a standard bulb?