brakes Big Heavy Battery Causing Uneven Braking

[73touring]

My touring locks on the front right first. Has new calipers

Disks pads. Was wondering if the really heavy battery in my

02 could be causing it?

[c.d.iesel]

BATTERY ? no

but defective 'new' rebuilt calipers will,

blocked fluid hose not releasing pressure will,

really poorly bled system will,

some suspension/steering disorder will

what other work was done? just brakes??

was it pulling BEFORE brake work ?

[Conserv]

Not only is there a 30 lb. battery on the left side, there is always a driver on the left side (LHD versions) with nearly half of his/her weight being distributed to the left front wheel. And then there's a steering box and column et al on the left. And instruments... Based on such a flawed analysis, you might conclude that the extreme heaviness of the left front corner makes it difficult for the left front brake to lock up that wheel (as compared to the relative lightness of the right front corner).

Still, I have had 3 different '02's -- '67, '70, and '76 -- with batteries in their original left front location, and have never noticed any particular tendency to lock the right front wheel.

Steve

Edited September 25, 2013 by Conserv

[Arizona02]

After driving and getting the brakes hot, jack the front end up and spin the tires by hand to sse if the brakes are dragging.

[73touring]

Steve. The car is Rhd.Trying to figure it out. Bled well. Prolem existed before had but more

Amplified changed due to sticky calipers and warped disks. Has twin servos and all the complexity they

Unnecessarily introduced due to them. Wheel beirings seem good suspension quite new and billies up front. Well adjusted fairly new drums and cylinders in the rear. Servos are e12 528i

[M3M3]

not battery issue.

 

if ever something changes in what a car does, first thing to check is the last thing you changed. 

[FB73tii]

some suspension/steering disorder will

 

+1 ^^. This may not be your issue at all, but sometimes there are multiple factors and perhaps something in the suspension getting old, sticky, binding, etc. may be getting worse and just happened to time itself with the brake rehab which perhaps made it more noticeable.

 

I went through a hell of a time figuring our a similar issue after a major brake upgrade. In my case, the car did not pull or lockup before the upgrade. Then I went to big rotors and Wilwood race calipers all the way around and the first time I drove it in the paddock the right front tire just locked up very easily, even at low speeds. I went through making sure everything was bedded, wheel bearings properly tightened, front alignment correct, tires OK, swapped master cylinders, replaced hard and flexible (braided) lines, etc and nothing would make it better. After all this I swapped the front calipers right to left and no change, the right front still locked up. I even installed hydraulic brake line pressure gauges to read the line pressures on each side and found everything OK.

 

I finally started looking at the car frame and suspension, suspecting something not right. I played with corner balancing, and also found my front sway bar had some pre-load I didn't like. At one point I had the front strut out and found a lot of resistance to movement of the control arm, like the thrust rod was inhibiting movement. For this reason eventually I'll build a heim-joint front subframe and control arms to make sure movement is free.

 

I never did find the "smoking gun", but eventually after cleaning, lubricating, adjusting, tweaking, and just driving the damn thing it went away. Since then I have gone to a Tilton dual overhung master with adjustable bias bar (unboosted) and the brakes are rock solid with no pull. So what I am saying is, it may be time to stat looking outside of the conventional "box" to other factors that may be influencing your brake problem. But, if you can, swap on another set of calipers (and pads!) and see if the problem is still there. Let us know when you figure it out.

 

--Fred '69 & '74tii (both with brake booster delete)

Edited September 26, 2013 by FB73tii

[Arizona02]

Replace old rubber brake hoses at caliper and check the push rod adjustment from the pedal to booster m/cyl for freeplay. If it is too tight the master cyl is being applied which should affect both front brakes.

[02Les]

Interesting!

My Touring (RHD) has the same problem. The severity of the right front lock up varies; can be quite scary at times.

Mine had been in storage in the UK for 10 yrs before I shipped it over here, and on arrival here the problem started. I have replaced everything brake-wise except the twin servos and the hard brake pipes. I have new (refurbished) servos from Jaymic but have not got around to fitting them yet.

My assumption (as everything else has been replaced) is, the servos (or one of them) are the problem.

[73touring]

Its one of those odd ones. The brakes have never been right but its more annoying the more money I spend on them

. One anomaly is that the flexy hoses are peugeot 405 in origin are a few years by now. I may just change them out for braded hoses.

[allbim]

My touring locks on the front right first. Has new calipers

Disks pads. Was wondering if the really heavy battery in my

02 could be causing it?

If it is a weight issue, then every 2002 would have that problem.

[Preyupy]

If you really want to know put it on scales and see what the corner weights are. There is the possibility that over the years springs may have lost some rate or even been changed with a non match pair. The sway bar might have mis matched links and it could be introducing weight jacking. Something might be bent, one shock might be locked up. Caliper piston(s) seized? Blocked brake line? These are maintenance issues, try them first! BMW did not screw up on the basic design of all 2002's. On top of that if just the weight of the battery was enough to cause your problem then all the cars that have the battery moved to the trunk would be suffering the problem but on the other side.