55 Buick Redliner Speedometer Fell apart!!

I have a 55 Buick Special, with the optional Redliner speedometer from the Century models. The original owner told me it used to give him trouble and just stopped working one day. Well Apple Hydraulics let me down and my treadle vac wont be ready for Led East, so I decided to start another project on the car. I pulled the dash out and removed the Speedo which was a lot harder than people made it sound. I carefully pried the bezel off and when I got it off it turns out everything was laying in there... The dial was laying on the back part which some how unscrewed itself from the speedometer. I spun the part where the cable would attach and I can get the post the dial would attach to, to turn, but it doesnt seem to return and it sounds kind of noisy like it needs oil. How hard is it to take this apart and lubricate it, then reassemble it. I figure its broken already I might as well try before I send it out.

Here are a Picture. If you look you can see the chrome screws are still attached to the chrome part of the dial its strange.

Removing the 2 screws on the back of the case should allow removal of the mechanism for further work. The trip reset cable may need to be removed also-- can't remember.

Does the dial "pointer" shaft return to the at-rest zero stop by turning the input shaft a partial revolution in reverse? The input shaft spins a bar magnet that sits inside an aluminum cup which is attached to the pointer shaft. As the magnet spins, the cup starts rotating slightly to indicate speed. When the magnet slows down and stops, a spiral spring returns the cup and pointer to the at-rest position.

The magnet should not touch the speed cup. If the unit is worn out, the input shaft can wear out the bore to the point the magnet can drag on the speed cup. When that happens, the pointer typically pegs out off the top end of the scale while operating. When car is stopped, the pointer is liable to come to rest anywhere on the scale. Backing the car up will make the pointer reset to 0.

The mechanism should not make noise. A scraping noise typically indicates the magnet is dragging.

The speedometer typically lasts over 100k miles, but if it shows 162k may time for a rebuild.

For testing, take a piece of small diameter plastic rod and file a square tip on it to fit the input shaft. Then insert the rod into a variable speed drill for testing the speedo. 1000 rpm equals 60 mph.

How those faceplate screws came loose is mysterious. Usually they're hard to break loose. Maybe someone attempted an earlier repair and just set the pieces back inside loose.

I took the back part apart and it definitely has been messed with. the clock spring that makes the pointer shaft return to zero is broken and then someone tried to re wind it and now it looks like the fuzz on the end of a cheap toothpick. The scraping I heard was the spring rubbing the housing and the bearing behind the dial. Not sure if I wasted money or not but I bought a 54 Special Spedo off ebay. I am going to try and transplant the post and spring assembly into my housing. Everything actually looks tight in mine and doesn't seem worn. Its just someone played where they shouldn't have.

Sounds like a good plan. There's lots of commonality in those speedometer heads built around the same time. I have a leftover '51 and a '53 that look the same as yours behind the faceplate. Both even have the light blue paint for the indirect lighting.

The return spring on the '55 may turn out to be stronger than the one on the '54. The '55 pointer only has to turn 240 degrees to go 0-120, while the '54 swings about 330 degrees.

I finally tracked down another redliner speedometer I bought it off eBay a couple days ago. Only problem I'm having is the mileage numbers on the one from eBay are white and mine are black. Also I would like my mileage to stay the same because mine was so low. how can I transplant the number's without ruining the spedometer, I really don't want to break it. It took me so long to find another one.

Attached is a 1962 dealer service bulletin dealing with replacing odometers. If I remember correctly the '55 Century unit is similar to Fig. 3. A clip or wire bail unsnaps from the odometer shaft to allow removal from the frame.

The procedure for resetting the main odometer is shown in step 5 if needed. If the unit is dismantled to this point, it's just as easy to replace the odometer with your original. Looks like that new one wound up with black digits on a white background like a 1950 unit.

I can verify that the procedure will be similar, many years ago, I replaced the sun damaged tumblers in a '52 speedometer with the ones from a '73+ series Chev pickup.

Thank you guys, I will try and take it apart tonight. I have clock oil left from lubricating the clock. Is that a good choice for lubricating the speedo? Ive attached a pic of the "New" one just for reference. I didnt know the "Redliner" was available on other years.... Is mine a different color because its an early 55? I know I have the Stromberg Carb and when I rebuilt my fuel pump it used a 54 kit from Cars INC.

There is a tiny "freeze" plug near the threads for the cable ferrule nut. Oil can be applied to the wick inside (sparingly) after popping out the plug. Greases were used on some of the gear train leading up to the odometer. The recommendation would be to use the same lubes only where GM did originally. Oil or grease will stain the odometer discs if it starts spreading. See attached info on rebuilding a '57 Chevy unit which is similar.

Buick also called the thermometer-type or ribbon-type speedometers in the Super/Roadmaster cars Redliners. Those were introduced on the '54 senior models. Buick kept it around through '61.

The circular-dial Redliner was used only in '55. It is similar to the '55-56 Pontiac speedometer. Buick however used two levels of color to make the red indicator span the 240 degree scale. Very clever.

Don't know how the replacement unit wound up with black numerals on white background. Buick's standard around then was white numerals on black background. It could have been rebuilt with odometers from some other year. Chevy and Olds were using black on white in '55, so who knows AC could have used the opposite color temporarily in Buick units.

https://www.classicchevy.com/assets/...hevy/37-32.pdf