I pulled an instrument cluster off a junker 80 300D. I know this is going to seem strange. How can I test the speedometer/odometer to see if it works without actually installing it?? Is that possible??. I have it apart now and the plastic gears look ok but want to make sure. Can I put something in the speedo connection to make it turn/spin? I don't have a car to put in to test it, want to send the part to a friend overseas.

look at the aluminum gear on the shaft even with the main odo numbers.
if you can turn it with your finger, it's loose and needs to be chamfored with a pair of pliers.
you can put a nail in the brass square hole where the speedo cable goes, and chuck it into a drill and spin it up to 50 or so mph, and see if the odo turns....

would that be the brass colored gear even with the main odo or the one just inside of that spins the initial number on the odo??

pete, the gear is gray aluminum.
the input where the speedo cable goes is brass.

check out DG's odo repair pictorial, it's got a screwdriver pointing to the aluminum gear that fails. right above the AHA! part.
http://www.dieselgiant.com/repairyourodometer.htm

When you are in the junk yard pulling out a speedometer, what I do, is have my electric drill. disconnect the spedo cable from the transmission, pull it out up to the left fender. connect the drill and spin it, and look in the window to see if the odometer, trip and spedo all work.

be sure the drill is in the reverse mode.

not sure how to check a w126 with the electric spedo.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

you have to pull the speedo out of the cluster and spin the motor drive gear (if it's still there...) odds are VERY good that if it's a 126, the gears have all melted.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I have a 126 spedo apart here on the desk. complicated looking thing being electric compared to the 123.
Don`t really see anything to spin. there is a shaft that is turned on the left side (looking at the face of it) that turns a small gear on the shaft end. (Right side). It turns a large brown gear which turns a yellow translucent gear. all contained in the clear plastic housing. which is connected to the printed circuit board.

I might get agressive with it and take it apart to see what makes it tick.
gears look perfect, and it probably works. got it thinking there might be a way to use it with a 2:47 Diff in a 123. don`t see any way.

OK off the main topic here.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

yup. that's the gear to spin. just spin it with your finger, and the odometer should turn. if not, something is stripped.

on my 116 I took the cluster out and used the battery drill on the input for the speedo cable. It took a little while to find the right little tool laying around the garage that fit in it, but at full charge i could get it to run at about 65mph, and i could check to see if the odometer works, and as said before the drill must be in reverse.

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__________________________________________
1987 300D(Erma)- #14 head, 193k
2003 TDI Beetle sold
1985 300sd sold
1987 300D(Ursala)- #14 head, 157k when sold
1987 300D(Wilbur)- #14head, 356,000+miles, sold after 7 days of owning it.
1992mercedes 300d- totaled and in a junk yard somewhere..
1983 mercedes 300sd- scrapped
1980 mercedes 300sd first mercedes diesel-sold

I pulled apart the speedometer/ odometer and noticed that the little gear thats sits between the aluminum colored odometer gear and black colored tripo gear has a broken tooth. Its an eight tooth white colored gear.. Can I match that up a hobby store or any suggestions?

ahh. no, I doubt it.
time to get parts from another speedo.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

I guess I was a little to aggressive in putting the odometer shaft back in and heard a little snap. Hopefully I have better luck when I start working on the ac unit next month with the evil servo and all the rest that comes along with it.

I think I found the gear I need. Here http://www.surplusshed.com/pages/item/m2994.html