Speedometer doesn't work

[macdude443]

Captspillane and I replaced my speedometer cable, as I burned through it while replacing the floor boards.  It used to work ok.  I can't get anything out of it now.  I'm thinking I put the adapter/gear the wrong way in the transfer case.  Is it ok to remove the bracket and rotate the assembly, so as to avoid draining it?

I'll take a photo today.  Maybe someone can tell me if it's in the right position.

[macdude443]

Here is a picture of the TC.  If anything, I think the plug should be rotated 180 degrees clockwise.  Thoughts?

[BenM]

If it's not engaging, 90 deg. CCW to bring the gears closer? I melted through one where the clip on the frame rail let loose and it landed against the exhaust.

[mudkicker715]

For the retarded like me. what does ccw mean.

[eagleman]

Counter clock wise= ccw

[macdude443]

I wish I had some sort of diagram of the inside of the TC.  I guess how I rotate it depends on where the gear is it's trying to mate with.  The adapter is black.  Can anyone take a look at theirs and see where it's sitting?  This is an '82, so I'd imagine it's a 129.

[BenM]

I don't seem to have a picture handy. The arrangement is pretty straightforward. The tail shaft has a worm gear on it. The speedometer cable has a fairly normal looking gear on it, it's a common Chrysler part.

The output shaft is above the speedometer cable. If you pull the end out you'll see the gear inside fairly easily. Careful, you lose some fluid that's hanging in the tail, but not much.

The higher, numerically, the rear end is, the bigger the gear on the end of the speedo cable because the drive shaft is turning faster. See: http://www.jeep4x4center.com/jeep-speedometer-gears/index.htm

The average Eagle, with small tires and a 2.35 rear uses a very small gear.

Anyway, they're both nylon gears and the one on the cable is retained with clips. They usually don't get damaged.

Start by just trying to twist it so the gear is up higher; the hole is round but the cable comes in off-center to allow for that adjustment. It could just be off by a little due to years of work.

If you're concerned, just pull it out and have a look around. You'll see how everything fits. Make sure the gear is on and that it can spin freely. If you take the gear off the end and you can (gently) pull the inner cable out, that's bad, the inner cable is anchored at the speedometer end and should just be formed at the transmission/transfer case end.

I hope that helps.

[macdude443]

Thanks for the info.  I figured if I pulled it I could see what I was trying to mate it with.  If I can get it working with no fluid loss, so much the better.  I remember the gear turning just fine when I put it in.  Nothing looked worn at all.

[captspillane]

I forget what we did there. You should have had a white speedo gear with your 2.35 gears, which is the smallest size commonly available. The teeth count is along the side. On my 3.07 station wagon I had a 29 tooth gear, and I think the white 2.35 gears are around 23 teeth. On the black housing piece should be three sets of numbers that represent ranges, like "32-38" next to a dot or "39-42" next to a dot.

Each dot next to the range of numbers corresponding to your teeth count should be down toward the ground. On some but not all transfer cases there will also be a dot at the very bottom. I can see that dot in your picture. You should try to get the dot on the black to line up across from the dot on the transfer case.

First you should try to find those ranges of numbers and clean them off so that you can read them. There should be three or four ranges there because there are only four possible orientations that lets the Ybone still bolt up. Rotate in the direction that makes your current range decrease to a smaller range. As you rotate the black adaptor make sure you also wiggle your front and rear driveshaft. Ideally you'll be in neutral and in 2WD so that you can slowly spin the rear yoke until your speedo gear has a chance to mesh up. It has worked for me in the past to just stay in 4WD and in gear and just wiggle the slight play in the yoke.

If you put your rear tires on ramps while leaving the front tires on the ground your transfer case will only lose a minimum amount of fluid when you pop the black adaptor. That's the only way to know if you inside teeth are good and to check the teeth count written on the side of it. The 13 Teeth in the transfer case drive gear is pretty strong. I've had a speedo gear eat itself up from being put on wrong, but the drive gear was still fine.

[macdude443]

I got it working.  The adapter was in the wrong position.  It only had one range listed, something like 2-35.  I turned it so the number was down at the lower dot (on the TC).  I also noticed that above the number, on the adapter, there is a triangular arrow-looking thing.  That ended up pointing straight above and above the lower dot on the TC.  If that makes any sense.

[carnuck]

Those ranges cover the number of teeth on the gear and yes, that does make sense. I had 17 teeth in one Eagle. May have been the one with 2.37 gears. I forget what was in my 2.72 wagon, but I'm switching to 3.08 and going 235/75/15 tires so I'll have to figure the correct match.

[Canoe]

...You should have had a white speedo gear with your 2.35 gears, which is the smallest size commonly available. The teeth count is along the side.
On my 3.07 station wagon I had a 29 tooth gear, ...
I think the white 2.35 gears are around 23 teeth. ...

I just replaced my speedometer cable & housing from my wagon's 128 to the cruise device/sensor.

• Axle is 2.72, speedo gear is blue and has 28 teeth.
  
• The metal insert end of the new cable housing was difficult to get into the red housing. Had to carefully assist the small o-ring on the insert into the housing using my finger nail.
  
• Once the o-ring was in, I put a tiny bit of RTV on the metal insert out to its flange, then slid the metal insert all the way in until its flange was against the red housing. That tiny bit of RTV bunches up to seal the metal insert's flange to the red housing.
  
• Secured the housing to the metal insert with the clip that aligns with the grove in the metal insert.
• To seal the red housing to the transfer case.
  Used a tiny coat of RTV in the housing o-ring groove and on the housing rim, then slid the o-ring into its grove, and a tiny coat of RTV on the o-ring.
  No RTV on the housing to the inside of the 0-ring grove, to ensure there's no bits that can end up loose and interferring with the transfer case in any way.
  Used paper towel to wipe the ATF4+ fluid off the housing where the, but didn't use a de-greaser.
  
• Just before installing the red housing into the TC, I slipped the clean gear onto the metal insert and secured it in place with its clip.
  
• At first I had the housing clocked 180 out as I thought the range mark should be algined at the top dot. Inner cable just spun as the gear wasn't touching anything.
  
• After some research, I re-clocked it with its red housing showing its 26-31 range mark at the bottom of the TC opening.
  
• Then the inner cable wouldn't spin, showing it was engaged with the speedo gear, which in turn was engaged inside the TC.
  
• Inner cable was sticking out too far at the front end. I pulled the inner cable out and trimmed the gear end until when inserted it engaged in the gear (wouldn't turn by hand), with the front end had the nut near but not touching the cable housing.
  
• Test drive and the speedometer shows 40 kph when the speed-radar-sign shows 40 kph. Drive with the arm a touch above and it shows 41 kph.
• But it had develooped a fluid leak. I found that I'd torn the o-ring when I re-clocked it... New o-ring tomorrow.