Speedometer Stopped Working As Mileage Rolled Over

Ok so i finally got a chance to test it today and unfortunately, the speedo is still on the fritz :/ It randomly jumps up to different speeds, sometimes even to 90+, freezes, and then comes down a bit before getting wonky all over again.

I tried unscrewing it a little bit and a lottle bit haha. Each time it relieves the tension on the back enough for the needle to drop to zero again but then when I start driving, it gets crazy anyway. I tried changing the angle of the cable under the dash by zip tying it to different spots. Thinking it maybe was binding because of the angle, but no luck.

The odometer still works as do the other gauges so I think that's a sign that the transfer case end is still working.

Maybe next I'll just order a new unit and cable and see what that does. Anyone know an easy way to pull the speedo assy without having to take the whole dash off? lol Took the better part of a day last time and definitely left a few new scratches/chips in the aftermath. :/

 

I usually unbolt the dash and tilt it back so I can get at the four nuts while sitting in the seat, but if you are younger and more nimble than I am you can get to the four nuts from underneath.

If you order a "new unit" it will likely be Omix-Ada and while they are pretty you don't want one.

Peter Debella had some NOS speedometers at one time, don't know about now, but they aren't cheap.

Have you replaced the cable, or pulled it out and lubricated it? Lots of times the cable is the culprit, and you don't want to spend $$$ on a speedometer and after installing it find you still have the problem.

 

X2. It helps if you are left-handed, double-jointed, and like standing on your head. But it can be done.

 

best view under dash . is sitting in that big hole with transmission out

 

Hee Haw! Yep, but I still think unbolting the dash panel and tilting it back is easier than removing the transmission.

Most of the Jeeps I have owned in my life have been flat fenders. When I got the CJ5 and saw that the dash could be unbolted I nearly jumped for Joy. The CJ5 had suffered a small fire under the dash, and rewiring was so easy with the dash unbolted, compared to doing the same in a CJ2A.

 

I put in an order for some stuff from kaiserwillys last night including a crown speedo before having a chance to read this. I'll try first swapping the cable to see if that helps my old unit function again.

I have already pulled and lubed the old cable. I also tried cutting a tiny bit off the length of the core but It didn't help. Maybe a new cable will work.

 

The bottom end, I hope.

 

So..... about that........
I'm embarrassed to say.... nope... I cut it off the top end cause I thought too much was getting pushed up against the back of the speedo collar. OOPS!

Just for future reference, whats the correct actual length the core needs to be? When the new one gets here, I now have higher hopes it will resolve my issue.

 

That is correct. But it may be the top ferrule, not the tip, pushing. In either case it is getting pushed from the bottom, and that is where to relieve it.

 

My cable had a fixed stop or crimped on ball at the speedometer end. Not sure on the correct length but it required cutting at the speedo head end.

 

"My cable had a fixed stop or crimped on ball at the speedometer end. Not sure on the correct length but it required cutting at the speedo head end."

Could be.

I was thinking of the universal core kits that need to be cut to length, and the upper stop/ferrule tip crimped on. The cast ferrule tip should fit into the speedo fully, as designed. Same for a fixed stop.

In either case... My belief is that the proper length is when the core is dropped into the outer case, the stop or ferrule is bottomed out at the top of the cable casing, not by the core at the transmission end. Then, minus just a smidge to provide for free-running clearance when everything is torqued firmly closed.

 

It is also limited by how much length of the end is squared off. I ended up brazing the the end and grinding it off square on the head end.

 

Clever!

 

Ok I'm just trying to process what you said and make sense of it. Bear with me.
Are you saying I'd insert the core into the cable sheath at the top end until the ferrule hits the back of the casing in the cable itself. then, screw in the bottom end of the cable into the t-case (possibly while keeping pressure on the top end) in order to make sure the bottom end of the core is sticking as far as possible into the t-case until its screwed down. and if it seats fully while screwed down, trim a little off to give some clearance (just incase) beforre screwing the top end into the speedo?

Does that make sense? Otherwise, I have no idea how to measure the length needed in the core while its attached at both ends.

 

More or less.

If it was me, I'd have the transmission end firmly screwed down. Drop the core into the casing, twisting until sure it is engaged with the drive gear. Check that it fully seats inside the top end of the casing. If not, shorten the bottom end slightly. The point is to prevent it pressing into the back of the speedo when the top end is tightened.

Just my two cents. Some of you other experienced Jeepers, jump in any time...

 

Just wanted to post an update. I installed a new cable on my old speedo (67" OMIX) and it seems to have worked! It jumps around a tiny bit below 10mph but I wonder if it just needs a bit more lube. I gave the core a thin coat of vasoline before installing but maybe I'll try a tiny bit more to see if it smooths out. If not.... no biggie.

Otherwise, I'M SO GLAD TO BE ABLE TO KEEP MY OLD SPEEDO!

Thanks for all the help!