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> speedometer failure points, the quest of a safety certificate continues
swl
post Aug 5 2007, 09:02 PM
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Ok folks - next on my to do list is the speedometer. There are really only 3 points of possible failure:

The sender gear
The cable
The speedo itself

The old car was working when she went to sleep so I can easily swap out parts. Whats the most likely place to start?
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SirAndy
post Aug 5 2007, 09:06 PM
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QUOTE(swl @ Aug 5 2007, 07:02 PM) *

Whats the most likely place to start?


if nothing works, suspect the cable. if the odometer doesn't work, one of the gears inside has worked it's way lose (press-fit) and slid out of the way.
both are easy to fix.

sometimes, the speedo angle drive on the transmission breaks too ...
(IMG:style_emoticons/default/dry.gif) Andy
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type47
post Aug 6 2007, 07:24 AM
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can't you test the speedo by spinning the "piece on the back where the cable fits in" with a drill? some small device chucked into the drill and inserted where the cable fits in.
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swl
post Aug 10 2007, 04:57 PM
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Jim,
Yup. The cable at that end has a slot in it. I used a slot screwdriver bit in it and could run it up to about 60MPH with my drill. Trick is you have to run the drill in reverse.

So now I have the problem isolated to the angle drive. Is it going to gush oil if I remove it? I assume yes both from the design point of view plus the fact that it is leaking. Whole damned tranny is. I really should be putting the tranny from my old car in but I'm in a hurry to get this thing plated.
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Slider
post Aug 10 2007, 06:54 PM
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Is there a How To on repairing that gear for the odometer im thinking that is the issue with mine the speedometer works fine but the Tripometer and Odometer dont work.

any help would be appreciated..
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swl
post Aug 10 2007, 07:06 PM
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try this one Chris.

http://www.pelicanparts.com/techarticles/M...auge_repair.htm
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Slider
post Aug 12 2007, 05:15 PM
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QUOTE(swl @ Aug 10 2007, 06:06 PM) *



Thanks i forgot about all of the tech articles at pelican..
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BarberDave
post Aug 13 2007, 06:16 AM
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(IMG:style_emoticons/default/smilie_pokal.gif)

Sorry for the Hijack

New rebilt Speedo,when i start to drive.it does't move , a couple of min. later to 10 min it works ok ??????? Anyone experience this?????
Dave (IMG:style_emoticons/default/slap.gif)
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swl
post Aug 13 2007, 05:11 PM
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Does it do this all the time Dave? From what I've seen poking around the drive chain is pretty much all or nothing. I'll know better when I get the failed angle drive apart and see what caused the failure.

My best guess is that the mechanism in the meter is sticking. When the vibration/speed gets enough to break it loose then it performs normally. I haven't had one apart but I'm assuming that it is just a little generator that produces current according to rpm and drives a standard galvanometer from there. There could be a problem with the seating of the needle or something like that.

If it fails every time you start it up from cold try the drill trick. If it doesn't work with the drill it would support the theory that it is the speedo itself. If it does work hook it back up and drive it. If the speedo works with the drill but not not when driving then you may be looking at the angle drive.
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Cap'n Krusty
post Aug 13 2007, 05:53 PM
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Removal of the angle drive, using the 27mm nut, doesn't open the tranny. Removal of the drive pinion assembly does. The Cap'n
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swl
post Aug 14 2007, 07:58 PM
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First of all the failure was for sure at the angle drive itself input and output disconnected.

Things I learned:

With her butt up in the air (ramps) the transmission oil did not gush. Ooze would be a more fitting description. I had the replacement in hand and only lost about an ounce of oil pulling the old out and pushing the new one in. Nothing at all dramatic.

The Cap'n approach to just remove the angle drive with the 27mm nut would have been a totally acceptable repair. I would say, however, that I think it would still loose a little oil. There seems to be a journal in the barrel that lets oil into the worm gear. It would leak very slowly but if you are leaving it overnight or a couple of days you want to plug it up a bit.

If you decide to remove just the angle drive with the 27mm don't go all neanderthal with the wrench. The only thing that keeps it from moving is that little locking bolt. It only goes down maybe a quarter inch into the barrel. The barrel seems to be aluminum. It may just be me being overly cautious but I could see bad things happening there. There should not be any problem with that nut being seized - steel bolt into aluminum threads with lots of oil behind it. Should be no problem. If it is though be careful.

Given the number of "me too's" on Dr Evil's thread it is probably best to have a seal kit for the replacement angle drive. That will require pulling out the entire assembly.

I found another answer for the "what is the differences amongst the years" contest. The older car (08 72) has a different angle drive than the newer car (02 73). The pictures in Mike's threads show the newer one. I'll post a pic of the older one on his thread once I find the bloody cable for my camera. The older drive has two nuts on it instead of one. The second one is 22mm and has nothing to do with removing the angle drive. It is a lock nut holding the shaft onto the angle drive. The older drive has the shaft threaded on where the newer ones appear to be a press fit. BTW in addition to the lock nut there is a little pin through the body that engages the threads as another lock. I don't recommend you try to rotate that joint - you will mangle the threads a little bit. Nothing terminal but not good.
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