Bouncing Speedo? (1 Viewer)

[Seth_O]

As long as I have owned my '69 FJ40 the speedo needle has bounced around while driving. It typically swings between a range of 15-20MPH, and just bounces up and down as I drive.

Since the range moves up and down with my speed, feels like it's bracketing the actual speed somewhere in there.

I recently rebuilt my t-case and all the speedo components looked good, so I figured it was the speedometer itself. I finally replaced that with another used piece which looked good upon inspection - only to find it still does it. I also have a new speedo cable installed.

Any idea what would cause this? Or how I could fix it? Not mission critical (doubtful I am going to get a speeding ticket ) but annoying for sure.

 

[lingo]

I have driven dozens of 40 series they all do it. Some worse than others.

 

[cruiser_guy]

Try cleaning the speedo head. Often what happens is oil makes it's way up the speedo cable and gets all gooey in the magnetic part of the speedo head. You can clean that out with solvent and chances are that will fix the problem. I did it on a Corolla years ago and on the FJ55 a year or so back. Fixed it both times.

 

[lingo]

I will have to try it then as well. I have never seen one that didn't bounce

 

[Seth_O]

Try cleaning the speedo head. Often what happens is oil makes it's way up the speedo cable and gets all gooey in the magnetic part of the speedo head. You can clean that out with solvent and chances are that will fix the problem. I did it on a Corolla years ago and on the FJ55 a year or so back. Fixed it both times.

Cruiser_guy: Tks mate - I'll have to try that. I don't remember seeing any oil in the magnetic coil/dealy-o when I had it disassembled, but I'll give that a try.

Lingo: it's NEVER the wrong time to make bacon.....

 

[salguire]

The cable will build up crap at any low point, and if it gets too close to the exhaust it will cook it, mine burnt all the way through the housing and still worked but bounced.

 

[CruisinFJ60]

clean out the cable and the metal drive piece in there as well real good, then use some graphite lubricant or something real slick and make sure there are no kinks in it and it ill prolly take care of the bounce, however it doesnt bother me enough to do so.

 

[1911]

Clean and lube the inner cable. Problem solv-ed, unless the cable is so old and kinked that the inner cable has worn a notch in the outer cable, in which case you need to replace the whole thing.

 

[Seth_O]

Tks for the feedback guys. My cable is actually brand new (had to get a longer one built when I redid my drive-train) and the old one bounced as well.

I cracked open the gauge cluster tonight and cleaned up the speedo assembly, no change . I'll take a look at the cable itself and make sure it doesn't have oil in it, but my guess is I am just going to have to live with it.

 

[cruiser_guy]

Did you clean the cup thingy in the speedo housing? It takes more than a few flushes with solvent or something to clean it well and it's not easy to see.

 

[Seth_O]

Did you clean the cup thingy in the speedo housing? It takes more than a few flushes with solvent or something to clean it well and it's not easy to see.

Assuming you are referring to the little silver cup that the rod on the back of the speedo needle goes into (sorry for my poor terminology, no idea what that part is called) I cleaned it out with break cleaner. I cleaned it until the brake cleaner came out clear and clean.

After that I cleaned up the outside part of the housing where the speedo cable inserts, as it wasn't looking too pretty.

I'll check my cable, and if that doesn't take care of the issue attack the gauge cluster again. I've had that apart 3-4 times in the past few days - wouldn't mind taking a break from it for a bit before I get tempted to pull out the BFH.