W124 300E Brake Hose Replacement - Blind Plug Size

[Rahulio1989300E]

I just ordered parts for the replacement of all 4 brake hoses and the rear brake discs and pads. I was looking at the FSM manual's brake hose replacement instructions this evening and the procedure says to use 'blind plugs' to seal off the threaded connections which the hose normally connects to immediately after removing the hose.

My guess is that this done in order to prevent the hard brake lines from leaking everything out and filling up with air through and through which would make bleeding them that much more difficult.

Does anyone know the size of blind caps I need?

[Hirnbeiss]

If you are doing a quick replacement, that should not be an issue. You need the plugs if you leave your hose disconnected for awhile.

[ps2cho]

I had no issues. If you use a power bleeder, you'll be fine.

Make sure you use PTFE on the threads of the bleed screw.

[S124300]

Our project 300E sat for a couple of months sans brake lines and fluid, yet it bled straight through without any bother using the two man method.
All new lines, hoses and overhauled calipers gave it a really light pedal, rather than the brick like pedal feel that it had at 9 years old until a strip down at 17 years old. It was the rear calipers causing the hard pedal.
To limit drain down in the master cylinder while all the pipes were disconnected I folded a piece of clingfilm in half - to achieve a double thickness - and put it on the fluid reservoir filler opening before tightening the lid down.

[Rahulio1989300E]

Thanks for the advice everyone. The parts arrived this afternoon, but my Motive Pressure Bleeder will arrive next week. I will take on replacing a tie rod and center link for now, then do the brake work whenever the power bleeder arrives. I will take photos and post up a how to for all that may be interested.

Again, thank you all.

[sam77aus]

How did you go with it?

I will be replacing the brake hoses on my 300E soon. I ordered them yesterday but they will take a couple of weeks to get here. As you mentioned in your first post I also noticed they recommended the use of blind plugs to seal the brake lines. I assume that's not really necessary if your replacing the hoses quickly. Also the FSM mentioned the use of a special open box wrench part 000-589-76-03-00. Did you need this part or did you just use a normal open wrench instead?

[lorainfurniture]

Originally Posted by sam77aus

How did you go with it?

I will be replacing the brake hoses on my 300E soon. I ordered them yesterday but they will take a couple of weeks to get here. As you mentioned in your first post I also noticed they recommended the use of blind plugs to seal the brake lines. I assume that's not really necessary if your replacing the hoses quickly. Also the FSM mentioned the use of a special open box wrench part 000-589-76-03-00. Did you need this part or did you just use a normal open wrench instead?

Either two open wrenches or crescent wrenches. It is very straight forward. You can do a brake fluid flush while you have everything open.