924Board.org

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Clock stop rolling? As nice as it is to have your car stay "low mileage" you probably want to fix the odometer when it mysteriously stops. This is a common problem with our cars, and if you own one long enough it is bound to happen to you at some point.

Luckily it is a simple fix. When I did it, it only took 30 to 45 min.

The first step is to remove the gauge. It is not all that hard.
Remove the steering wheel.
Remove the plastic upper and lower column covers.
Remove the turn signal assembly.
Remove the two screws holding the dash bezel in place and pull it out enough to undo the speedo cable and all other connectors on the gauge, and pop the gauge out the front of the bezel.

With the gauge out use a screwdriver and work your way around the rim of the gauge bending the metal flange up so it can be removed. It is crimped on and must be removed to disassemble the gauge.

Remove the sensor from the back of the speedo and the two retaining screws. The internals will then slide out of the housing.

This is the little bugger that stopped my clock. The gear teeth were chewed off by the worm over time.

A good gear looks like this.

The gear can be removed by using a punch or a nail and driving the pin out from the opposite side of the red worm gear. This pic is of the donor speedo that I stole the gear from.

I put a little lube on the "new" gear and put it in place, pressing the shaft back in with a pair of adjustable pliers.

Everything is the reverse of removal. To crimp the ring shut I just used the same screw driver and worked my way around the edge pushing it flat. The metal is pretty soft so it was not too hard.

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

Can you tell me the part number or the number of teeth that the gear has? I would really like to go ahead and order the gear so that I have it sitting there waiting on me to rebuild the gauge.

Here is a link with all of the porsche gears listed:

http://www.pelicanparts.com/catalog/shopcart/944M/POR_944M_ELgage_pg3.htm
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1980 924 NA
1982 931

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

nevermind upon further inspection, pelican has a tool telling me that it's the M17.

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1980 924 NA
1982 931

Scorpio · Posted: Sun Feb 21, 2010 5:41 pm Post subject:

great how to joecitizen!
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1979 NA
MS1..EFI..
GARRETT T25 TURBO
BILSTEIN SHOCKS
GT BASED CUSTOM BODYKIT

Brisbane , Australia
Think mean think fast
all youll see is
my Porsches Arse!!!

thelm1249 · Joined: 13 Oct 2009 Posts: 7 Location: Spring, TX

I noticed you said to remove the turn signal arm and the steering wheel plastic housing, but on mine I can't figure out how to remove the plastic housing and the turn indicator seems to be plug in on the back. I must be missing something but what? I removed the four screws on the turn signal assembly but it won't come out. Can you help me?

Grenadiers · Posted: Tue Apr 27, 2010 2:23 am Post subject:

I've removed the three-hole gauge bezel and the speedo without removing steering wheel. Not sure why this is listed as a requirement?
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'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

thelm1249 · Joined: 13 Oct 2009 Posts: 7 Location: Spring, TX

With my hands I need to remove the steering wheel just to get a little more room to get the the speedo cable.

flosho · Posted: Tue Apr 27, 2010 2:42 am Post subject:

Grenadiers · Posted: Tue Apr 27, 2010 2:56 am Post subject:

You should have seen all the beer that magically disappeared yesterday!
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'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

thelm1249 · Joined: 13 Oct 2009 Posts: 7 Location: Spring, TX

You mentioned about taking off the surround of the steering wheel and the turn signal assembly. How do you remove the surround?

9XX Girl! · Posted: Sun May 09, 2010 10:00 am Post subject:

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

There's links in the Links section to some suppliers of replacement speedo gears.

It can be slightly more challenging removing the speedo in a right-hand drive car as the speedo cable is often pulled tight. Getting under the bonnet/hood and pushing more cable through the firewall helps.
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1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

Johann · Joined: 07 Aug 2016 Posts: 240 Location: Netherlands

Thanks for the DIY, I just did my speedometer using it.

mikeycrum14 · Joined: 19 Jan 2017 Posts: 110 Location: Juneau, Wisconsin

What is the part number for that gear. Mine just went bad and it's my dd car.
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1981 924 - Alpine White, First car! LSD. - SOLD
1989 Foxbody - Oxford White Turd
1992 Miata - Freaking Red
1987 300zx Turbo - Also White
1991 Miata - White field find
1987 924S - Alpine White, Offroader Build, possible future TDI swap

Ozzie · Posted: Sun Apr 02, 2017 9:22 am Post subject:

My problem is the red worm gear slides down the shaft and disengages.
any ideas?
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance