Good day everyone,

I have a 1981 300D that I have owned for 6 years. Recently, I have stumbled into a very strange problem. Driving home from the airport one night, I felt the car 'hesitate', upon paying closer attention, it seemed to me that the brakes were 'momentarily' engaging. When I say momentarily, it was only for an instant, but it kept happening every so often. So, I slowed down and made it home without incident. Upon pulling in to the garage and exiting the vehicle, I smelled the 'burnt brake smell' coming from the rear brakes, mostly from the left side, but somewhat from the right side. The left side wheel was hot to the touch, and the right side was warm, but not hot. The next day, I ordered and new master cylinder, a new left rear brake caliper, and new brake pads. I decided not to do anything with the right side for the time being. When the parts arrived, I installed them and assumed the problem was solved. Driving at fairly low speed around town, the phenomenon did not reoccur. However, a week or so later, when driving at higher speed on the interstate, I noticed it again. Particularly when driving up hill at over 60 mph. The wheels are not hot to the touch, but I assume that if I drove for a substantial length of time they would be. Any ideas what may be causing this? I figured replacing the master cylinder would have addressed any control issues. Thoughts?

Thanks

Is the right side still getting hot?

Folks often suggest replacing the brake hoses at this point.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I don't think we have enough information, but My first thought is that the parking brake may be engaged.

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I could not own any MB without the help from you...fellow forum members.


83 300td 207,XXX

Replace the brake hoses and try again.

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1981 300TD 310k miles
1970 280sel 172k miles
1966 230 Fintail 162k miles

"Where are we going? And why am I in this hand basket?"

One of the Forum Member suggested that if both rear or both Front Brake Calipers were Sticking it was the Master Cylinder.

If one Caliper was sticking it was the Brake Hose.

I think on used Calipers there is a maybe to the above because gunk can be in one or both front or rear Calipers and cause similar symptoms.

But, sinc you replaced the Caliper on one side it may well be an issue with the Hose.

Another issue could be if the old Fluid was not flushed out of the Brake Lines more there could still be gunk to bind up the Caliper Pistons.

It would not hurt to check to see if your Wheel Bearings have too much play.
Checking the Bearing End Play is best done with a Dial Indicator but if you Pull and push on ther Brake Rotor (make sure the Rotor is bolted down) and can feel Play you might have an issue there (at that point it would be a good idea to check with a Dial Indicator to verify).

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84 300D, 82 Volvo 244Gl Diesel

Hey, thanks for the responses. BTW, as a precaution, I also replaced the left rear rotor. I replaced the brake fluid and purged the line to the left rear somewhat during the bleeding process. The parking brake is not engaged and the wheels have not been hot to the touch. However, the problem still persists and appears to be worsening this morning. After reading elsewhere in the forum, yesterday I ordered two replacement hoses for the rear and I will make sure to pump some fluid through the lines when I install them. What else is there?