Sould I adjust brake booster piston rod?

[Ryan S.]

Looks like some D owners have adjusted brake booster piston rod to shorten the pedal travel. Compare to my other modern cars, D's brake seems much soft and require more force to stop. Other D owners have told me that mine is normal but I am wondering I should adjust booster rod to get that tight brake feel.

Here is the link to the brake booster adjustment page. http://www.16908.info/?p=1605


http://lukesandel.com/auto/delorean/repair/brakeboosteradjust.html
"This new brake master cylinder often requires adjustment of the brake booster piston rod to avoid extra pedal travel when braking. If after installation and proper bleeding you experience a low pedal remove the two 17m mounting nuts and pull master cylinder away to allow access to booster (you can leave brake lines attached) adjust booster rod using 8m socket wrench to adjust rod. Have someone depress brake pedal or use appropriate length bar wedged against seat bottom to allow access to booster pin and hold with pliers while adjusting 8m rod setscrew. Mark socket with a black magic marker and turn rod counter clockwise to lengthen. Usually two to three full turns are required to give a good solid pedal. There should be at least 2" of pedal travel before brakes apply or dragging and subsequent rotor damage may occur. After adjusting road test car and then check wheels for brake dragging before you're done."

[David T]

There are only 2 reasons you would adjust the pushrod.
1) the brakes never fully release
2) too much pedal travel before the brakes work

A very small adjustment makes a large difference so do it in very small increments. You do not have to disconnect the brake lines, just undo the 2 nuts and move the master cylinder enough to get to the pushrod. Use 2 wrenches, one to hod back.
David Teitelbaum

[Ron]

+1
If your pedal is soft, you have other problems which need to be addressed BEFORE you do any rod adjustments...

[EdR5150]

Here is the link to the brake booster adjustment page. http://www.16908.info/?p=1605

That's my blog! As I said, my brakes never felt spongy or soft, there was just too much travel in the pedal. I also had another prominent club member and techie drive my car, and confirmed my thoughts on the pedal travel. My guess is at some point in the past, the rod was adjusted to compensate for a different master cylinder. After another master cylinder change, new pads and rotors, the rod was never re-adjusted. Unless I missed it, the rod adjustment is not covered in the workshop manual.

[David T]

The pushrod adjustment is NOT in the manual and you are correct, some master cylinders do seem to require a small adjustment. Most of the time I see it needs to be shortened because the brakes have not fully released. On one car the brakes were SMOKING and the rotors were glowing! About 1/8 of a turn was all it needed.
David Teitelbaum

[jawn101]

Ryan, how is it feeling now that you picked it up from Wolff Motor Werks? Any better?

[vwdmc16]

Yeah to me the brakes in your car didnt feel too squishy Ryan, Im considering adjusting my brake rod too so there is less travel.

[Ryan S.]

Clint, thanks so much. Car feels 1000x better with not vibrating when braking. For the first time, I had a great time driving my D. :driving1: Man...You are good.:worship:


Sounds like I shouldn't touch that rod. I think I just need to get used to with D's brake. Just need to press harder. I guess I shouldn't compare D against my other modern abs brake cars. Clint, let me know if rod adjusting works or not for you.

I found the source of fuel ordor. Fuel is still leaking through the new fuel combo unit. I will reinstall it again for the fourth time. Not sure if i am doing something wrong or the seal is bad. I am really getting sick and tired of this fuel ordor issue. :banghead:

[David T]

If the pedal is soft and/or squishy you may still have air in the system and/or the hoses are swelling under the braking pressure. Replacing all 4 with S/S braided hoses will give you a firmer pedal. As for the pushrod, see if the car will roll easily once everything gets warmed up. Also watch your gas mileage and after a long drive see how hot your brakes are.
David Teitelbaum

[Ryan S.]

Thanks David!!!! Yes, SS hoses are on my list of things to do.