Quote:
Originally Posted by Hellcat94
because the Dealer gave me a vacant stare when asked the same question, and I hate blind firing.
|
The parts dept usually has no way of knowing what is different on a 34 year old car beyond asking for the VIN. Did you get a MC from the dealer?
Quote:
Originally Posted by Frank Reiner
Physically, either one will bolt to the booster.
The earlier one has a 15/16" front circuit bore, the later one a 1" front circuit bore. The change in bore results in a difference in pedal feel & stroke.
|
There is more to it with a stepped bore MC. The front 15/16" will have slightly more front brake bias than the 1". The 1" will require a slightly more force to actuate the brakes.
Quote:
Originally Posted by Hellcat94
Ok so I actually bought the earlier VIN ATE Master Cylinder 0044300901 and it has no fitment problems as far as i can tell. I ran into a problem though. My brakes are gargantually heavy and require immense effort to stop the car. I get about 2 seconds of booster pressure then the pedal falls to the stiffest spot on earth before the metal, accompanied by a gas leak noise, and then if I try to bring the car to a complete stop, there is a loud clunk you can feel from behind. I beleived the Oring on the m/c was bad so i went to change it with a fresh spare i had on hand. 8 hrs after I drove i went to get to work and when I uncoupled the booster line the vacuum rushed to equalize, indicating the booster held vacuum, and a later test with a the new oring on and a mityvac in hand confirmed the boosters air tight. *I love that.*
|
This is all over the place and difficult to read all bunched up. From what I can make out:
Brake pedal travel is long and soft until it hits bottom then the brakes sort of work. This is usually a sign of either the front or rear brake circuit not working / holding pressure. It is likely the rear not working, if none of teh wheels are locking up. If the front stopped working, usually the rears will lock up when trying to stop the car. However see my last entry *
If the hiss is under dash, the brake booster has failed. The rear clunk can be a lot of things. ( like a caliper falling off. )
Quote:
Originally Posted by Hellcat94
Could it possibly be the booster's pushrod? Can you adjust an 83 300SD booster pushrod & if so how do you do it properly?
|
* It is possible to have a MC with a deeper push rod socket, this would lead to a long travel pedal because the booster isn't pushing against anything until late in the travel. Compare both MC / measure push rod on the booster.