1984 Mercedes 300d. I am looking to change the front caliper brake bleed screw. The current one on there is leaking. What are the dimensions of the front?

You could identify what make of caliper you have and use that info to go on the internet at an auto parts store like AutoZone and see if they have any bleeder screws.

One of the sealing issues can be that the tapered area that the screw seat on to seal is rusted and pitted or something hard got between it when it was tightened and the seat or tapered end of the screw is dented or deformed.

Meaning the screw dose not seal on the threads.

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84 300D, 82 Volvo 244Gl Diesel

google this SPEED BLEEDER all the sizes are on there under vehicle aplications .

It is either 9, 10, 11 or 12 mm. Make sure you get a box end to always break it loose with. Also I put a little Kroil on them.

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Jim

I find that cleaning out the hole in the nipple with a drill bit thats a snug fit and leave it in as you remove the bleed screw .This will give it extra srength .

Depends on whether it has ATE or the less common Bendix calipers, they have different size bleeder screws. I believe the ATE are usually 11mm, Bendix are 12mm if I recall correctly.

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-diesel is not just a fuel, its a way of life-
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Btw these are OEM calipers. I Ended up taking out the old ones and getting them measured m8 x 1.25 x 1.5

The break calipers on a W123 are not made by Mercedes. They are generally ATE or Girling. (Bendix?)

You can even have one make on the front and the other make on the rear.

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84 300D, 82 Volvo 244Gl Diesel