I was thrilled to follow the dieselgiant's DIY routine for speedometer repair on my 1983 300D (W123). The procedure worked for about 1K, but has now stopped.

I didn't use Loctite on the repair, so I guess I'll open it back up and try again.

Any advice from people who had to do this repair twice?

Thanks.

My advice would be to nick the shaft with bolt cutters, I've done this fix many times but never twice on the same car.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I use wire-cutters. (Bolt-cutters could nick the shaft in two) Nick the shaft just enough. Too many nicks make the shaft harder to press back in place.

Happy Motoring, Mark

__________________
DrDKW

So did you use the Loctite as others have recommended or was it enough to just scratch up the shaft? (I'd love to skip the Loctite, if possible.)

Nick the shaft lengthwise so the gear is working against the grain. I didn't use any loctite and its worked great for me.

I had a shop do my 300D the first time. They put new gears in the speedo head, but didn't score the shaft OR use loctite on the gear. The result was a repair that lasted 12,000 miles. I took it back apart and scored the shaft with a screwdriver. That was about a thousand miles ago and so far so good.

__________________
Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

OK, the BEST method for nicking up the shaft is to use small vice grips squeeze the shaft well with the end, and it will make a series of close small dents along the shaft that will NEVER let go of the gear!

__________________
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 used one of those electric engraving tools to scar the shaft on China. Has been working for almost 15K. I did not use any Loctite or glue.....

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

The VDO odometer on my 83 BMW bike just started slipping. I assume it's a similar design, I'll have to take it apart when I get a chance.

Nothing about this job is "idiot proof"

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I don't see how one can get Loctite or super-glue in there without gettinng it on other parts that shouldn't be glued. Just several nicks with a wire cutters or other tool - enough to raise the surface of the shaft sufficiently to grip the primary grey pot-metal drive-gear.

Happy Motoring, Mark

__________________
DrDKW

the thought of a drop of super glue in the wrong place has always has always detoured me from using it. The bolt cutters I use are a "small' pair, not the mongo ones usually seen, still capable of cutting the shaft in two if your not easy with the squeeze tho.

Everyone knows not to reset the "trip odometer" while moving, right? OK, just checking

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

I was fearful of Loctite for the same reasons stated above - no way to prevent it from going where I didn't want it.
I used a sharp center punch to raise material on the shaft just where the gear goes. This worked fine, and the gear became a nice tight fit.
The gear is made of pot metal, or zinc alloy, and will "creep" in time to alleviate stress. You could argue that it is a poor design, but heck, most cars aren't designed to last 20 years, much less 30 or more.

Not so. I bought into this tale for years and then when I had to operate on the mechanism I examined it carefully. NO....IT CANNOT BE DAMAGED BY RESETTING WHILE MOVING.

This one has to go the same way as the one that says incorrect stop light bulbs will damage the cruise control amplifier.

Like Rolls the Benz has its own fables. It was and is still believed by many that at purchase the hood is sealed and can only be worked on by a Rolls Royce mechanic from the factory.

__________________
Dionysius

Huh, well thats interesting, think I am too set in my ways to change tho, the hood of my Rolls is gona stay sealed.

__________________


1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"