TheSamba.com :: View topic

Fri May 02, 2003 9:24 am

I saw the message about the squealing brakes and will try that for my squealing problem but when we press down hard on the brakes on our 78 Westy the brakes are starting to pulse. I just put new pads on and I am pretty sure the rotors are straight. Could there be a problem with the master cylinder? My wife notices the brake warning light coming on more and more often.

Any ideas? Bleeding the lines? New master cylinder?

Tue May 27, 2003 10:11 pm

If you didn't have the rotors turned when you replaced the pads, warpage is most likely your problem. Try to have them turned - chances are, if they're turnable, that'll cure the pulsation.

Tue May 27, 2003 10:16 pm

And, warped drums can also be a culprit.

Tue May 27, 2003 10:30 pm

Yeah either that or it's your ABS letting you know it's working.

Tue May 27, 2003 11:06 pm

There are a couple of things to check. First are the calipers torqued to 116 ft. lbs? Have the pistons rotated in the calipers? The backing plates for the pads are supposed to keep the pistons from rotating but the tabs get bent and that can allow the piston to rotate and you'll get vibration especially under heavy braking.

You can still have pusling even though you replaced pads, rotors, hard lines, flex lines etc if you don't check those items. Also check to see what condition the front caliper dust seals are in. If they are torn then the inner seal is probably contaiminated and needs replacing also. Inexpensive item and ATE seals are still available.

You can isolate the rear brakes as the problem by applying the parking brake only to slow down. Any drum out of round will be felt as you do this.

As for the lighting flash it means you have a leak somewhere or there is air in the system and the switches trip as the primary section of the master cylinder pumps up but there is a small amount of air in the secondary (or vice versa). The compression of the air is enough of a delay to flash the brake warning light. Bleed the system thoroughly and see if the problem goes away.

Wed May 28, 2003 2:33 am

ABS on a 78 Westy?... LOL!

Wed May 28, 2003 9:30 am

What, your 78 doesn't have ABS? Geez!

Wed May 28, 2003 6:02 pm

Buses do not have a brake fluid warning light. They can not tell if there is air in the line nor do they have a recervoir level sensor or indicator. The little red "b" light on the dash is for the parking brake. Mine will sometimes come on when I am driving, the e-brake is out enough to turn the light on, push the e-brake lever back in all the way and it will go off.

Wed May 28, 2003 10:33 pm

have you hit any curbs lately? a bent rim will also give it that pulsing feeling

Thu May 29, 2003 10:14 am

the rotors are a good idea to check but the pulsing really can't be isloated until you are certain the lines are bleed properly...and bleeding is just a matter of having fun under your bus...

Thu May 29, 2003 10:16 am

Yes, I got a kick out of the ABS response also...lol..on that one...sorry folks..there's no abs on 78 westy's...

Thu May 29, 2003 10:27 am

Your rotors are warped, end of story...I work on these everyday...have your rotors turned, all will be well....