Speedometer/Air raid siren

Capt Kirk

Well-known member
I've been putting some miles on the 35 the last few days and the Max's rebuilt carb has the car running better than it ever has! Anyway, on the way to work this morning, with the top down, a few miles down the road the car instantly started making a loud hellacious squealing noise. After a little investigation, I thought it was the speedo cable because after a little wiggling of the cable it quit. On my way back home, it started again with a vengeance. I couldn't tell if the dog walkers and joggers were looking at the car or wondering why I was signaling the next apocalypse! It was loud! Half way home the needle was reading 85MPH and then fell off and the sound got louder. The cable is a new replacement when I restored the car and to my knowledge the spedo has never been serviced. What in God's name is inside a spedo that can make that kind of noise and is there anyone that can rebuild it? In the mean time, I will unscrew the cable.
 
Had the same squealing noise happen several years ago in my '35 fordor sedan on a cross country tour. I was pretty sure it was coming from the speedometer cable, so I pulled over and unscrewed the speedometer cable from behind the speedometer head. I totally removed the inner drive cable and stored it in a plastic bag until I arrived at the hotel where we were spending the night. I picked up a tube of dry powder graphite lube at an auto supply store, and that evening I wiped all the old gummy lube from the cable and applied graphite powder to the entire length of the cable, and put the inner cable back into the outer jacket. I fastened the cable back on the speedo and gave it a test drive. This totally eliminated that squealing noise for the last several years.
 
Unhook the cable from the speedometer. spray a DRY LUBRICANT inside the cable then reconnect. If if the "Siren" happens again, Hit the deck and avoid being strafed by enemy aircraft!
 
Looks like most responses think it's the cable. I will dry lube that and see if it works. If it does, is there a way I can get into the spedo to put the indicator needle back on? If it doesn't work, is there someone that can rebuild the spedo or do I need to start shopping for another?
Thanks
 
All of you guys suggested a dry lubrication such as a graphite powder. Just out of curiosity, what would be wrong with lubricating the cable with white lithium grease? Just wondering in case I ever have this problem.
 
Capt Kirk, It's relelatively easy to take the speedo housing apart, (with the speedo out of the car). Push the needle back onto its pin and see if it holds tight. If not try a VERY small dab of glue on the pin and put your needle on. Good luck.
Doug.
 
All of you guys suggested a dry lubrication such as a graphite powder. Just out of curiosity, what would be wrong with lubricating the cable with white lithium grease? Just wondering in case I ever have this problem.

Seth I do not think you could beat Lithium grease but you would need the cable out of the housing to do it.
 
I had the same thing on my model A, Old Rusty. I was glad I traced the noise to the speedo because I was just about to start pulling the engine and transmission! I disconnected the cable at the gearbox and to be honest, it's still disconnected. I assumed it was a dry bearing in the speedo, rather than the cable. It's just one more thing on the to do list.

Re the lube on the cable, many years ago I had a speedo that was bouncing and I used light oil to lube the cable. It still bounced like mad. I wiped it clean and used normal grease, like you use in wheel bearings. The speedo needle was nice and smooth after that. It is as if the cable needs the grease as a damper. Anyway, that's what worked for me, your results may vary.

Mart.
 
Seth I do not think you could beat Lithium grease but you would need the cable out of the housing to do it.

Thanks. I pulled a cable out of a 51 Crestliner 2 years ago and lubed it with white lithium grease and it has worked well since. Just checking.
 
On my '52 truck, the speedo has an oil point just ahead of the rear cable connection, you might put some 3-in-1 there if yours has it.
 

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Speedometers of the old variety functioned by the rotating of a magnet inside a close fitting cup that was attached to a clock spring and the indicator needle through a small shaft with little tiny bearings (generally jewel bearings). Hopefully it is just a dry bushing on the magnet drive end. If the bushing gets too worn, the magnet will start touching the drag cup and it will make a hell of a racket. If it calms down after lubing the bushing as shown by Ross F1 then it should go some more miles. If not, the bushing is likely worn out.
 
Graphite vs grease and or lithium --- over time grease and lithium will dry out and cause the problem you are trying to fix.
Either dry graphite or liquid graphite will be better after you clean the cable.
Like JM 35 Sedan says, clean the old gummy lube off.
Happened on my 49 -- cleaned and used liquid graphite. The floating needle and the screaming have ceased.
 
In addition to all the above, a dry lubricant does not attract or retain dust or dry out. That's why most everywhere on the vehicle that accepts oil or grease, a "Dust cover" is usually provided.
 
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