Stepdown Speedometer Repair

pseftoncomcastnet

Has anyone had the guts of their stepdown speedometer renewed/repaired? Mine doesn't need cosmetics. It just wavers a bit below 35 mph or so.

Peter S.

[Deleted User]

What year, what model?

pseftoncomcastnet

1951 Commodore, was an 8, now a 6.

Peter S.

bartibog1

have you checked the cable maybe a little graphite will cure your problem
Have seen this before
Steve

pseftoncomcastnet

I lubed the cable within the past 18 months and saw some improvement. The wavering between 15 and 35 mph continued, but the needle steadied itself by 50 mph and seemed to record an accurate 65 mph compared to a pace car. I'll make another pass with the graphite, as you suggest.

Peter S.

Frankvintagefullflowcom

The pulsation likely originates in the cable/housing, not in the speedo itself. Above a certain speed, the pulse frequency is too high for the needle to react so it appears to smooth out.
Have you removed the cable assy and cleaned it thoroughly including the housing ID? I suspect you'll find the goo from years of life in there that doesn't get removed by just lubing it from one/both ends. I think I'm suffering from that, too......but my speedo is fine.
F

pseftoncomcastnet

i didn't try to degunk the cable and housing, which now seems like it should have been an obvious second step. Did you use anything special to clean them?

P

Park_W

You might also put a drop of light oil in the little hole at top of the speedometer "snout," where the cable plugs in. Use a mirror to locate the hole, or feel for it.

SuperDave

Along with Parks suggestion.. BrakeKleen spray solvent will dissolve everything! Spray the inside of the outer cable from the top.. With the bottom end disconnected. You will be surprised at the junk that will come out. Then use graphite only. Grease will bind up in cold weather. Which might be part of your problem?

Park_W

I recommend, to anyone who's not aware of the oil hole I mention above, to get under there at the first opportunity and put a drop or two into that oil hole. A couple of years ago, while four hours from home, my Hornet speedometer let out this horrible screeching noise, the needle went wild, then everything stopped. The dry input sleeve in the speedo had locked up, then the speedo cable broke. Speedo rebuild and new cable required, all because I'd never oiled the back end of the speedo.

53jetman

To combat the wavering speedometer needle on my '53 Super Jet, I pulled the cable, cleaned it with brakleen and than soaked overnight in ATF. Re-installed it the next day, and it has performed perfectly ever since - that was six years ago!

mdwhit

Sometimes it is the cable housing, itself. I have seen a few, where the inner wall of the housing is worn from the speedometer cable rubbing the cable housing wall due to lack of lubrication. And, I have also seen pinched and partially separated winding of the cable housing.

mdwhit

Also, as Super Dave states, graphite is probably best to lube the housing with, but I have also used white lithium grease, and it has work well too.

Geoff

Also, make sure the cable is routed with the easiest curve possible, no sharp twists or turns.

RonS

Park, when you say the small hole, are you referring to the hole on the top of the fitting that the cable threads into? That is on top of the male fitting( 12 o'clock) as looking from under the dash to back of the speedometer. I doubt many owners knew it was there. I can't see it, I know it's there, because I had mine(53) rebuilt ,calibrated and installed a new inner cable because the needle was erratically "floating" a few years ago. If you have a spare, see what Park means.

lostmind

There was a Hudson bulletin for the lube point on the speedo. Maybe Alex has it posted?

Park_W

Yes, Ron, that's the one.

pseftoncomcastnet

these ideas would not have occurred to me in a hundred years. I'm gonna try them out when I get home to Virginia next week.

Peter S.

RonS

I find that a small eye dropper with some oil works well. It is really cumbersome to get a small can etc. in the tight confines. Remove the bulb from the rear of the speedometer. I take a small pin to kind of clean any dust that may have settled in the tiny oil cup. Place a rag near by, so oil doesn't mess the carpet.

StillOutThere

When you need speedo repair or recallibration, probably the best in the country is Bob's Speedos in Howell, Michigan. I sent one there UPS this a.m..

464Saloon

SW Speedometer in Downey Ca is very good too. He has repaired, rebuilt and recalibrated numerous units for me and people I have referred

Park_W

If dealing with a '50 or earlier car, be sure the speedo repair guy knows that Hudson used a different reference for calibration. Pre-'51 Hudson speedo's were calibrated for 60 mph at 2,000 rpm of the cable. The rest of the world, it seems, used 60 mph at 1,000 rpm shaft (cable) speed. The old-timer shops know this, but the newer folks may not. I had to convince a well known shop in SC that this was the case ... he refused to believe me, so when I got the speedo back it showed half the speed it should have. Sent it back, he tried to fudge it to read higher, but of course the odometer still ran at half speed. The guy finally subbed it to another shop, who calibrated it right.

[Deleted User]

I would like to second the oiling of the head of the speedo.I do think your problem is the cable but to reduce future problems don't for get the speedo head. If you can take the speaker out and still limber enough you can reach it through the speaker hole. Before you put the drop of oil into the hole take a straight pin and clean the 60+ years of dust out of it. I use the oil I oil my grandfather clock with. You can buy it at any clock repair shop.

[Deleted User]

Sorry Ron, I should have read all the post before I commented. You beat me to it. lol