disc break air help

[Gorde Lang]

2000Beaver marquis tourmaline, c12/ 425 cat.We finally got our coach back from bcs after 3 plus months. The brakes were finally done, or so we thought. We drove back to Vallejo without incident, 2 weeks later we took a 20 min drive & the same rear brakes just fixed got so hot it smelled like burning brakes. We are 8.5 hrs away from bcs.Any one out know who is qualified to diagnose & repair anyone near us.I'm coming up empty handed & have limited mechanical abilities

[Steve Huber Co-Admin]

Gorde,

http://beaveramb.org/forum/index.php/topic,1669.msg11700.html#msg11700

Also check out the attachment at this location for other possibilities in your area http://beaveramb.org/forum/index.php/topic,5250.msg39315.html#msg39315

Steve

[Jeremy Parrett]

after having the passenger side drive axle rotor/disc and pads replaced in Indio CA we also noticed a hot brake pad smell and   see brake dust on the passenger side drive axle wheel etc.  Is this a normal thing after new brake pads are installed or do we need an adjustment ??
  No other wheels have this issue.

[Joel Ashley]

Gorde, I hope you called BCS about this.

Joel

[Edward Buker]

Jeremy,

The fact that one wheel only is doing this would be an indicator that something is not right and should be looked at.
It may be that the slack adjustor is too tight or that the pads are binding and not fully releasing when the actuator is released. There may be an issue with how that pad and caliper was installed. If they used the wrong non clay based grease which is now expanding when hot, that could also be an issue but I would expect that issue would affect more than one wheel. You might check if they greased them per the Meritor procedure and if they used a Meritor clay based  grease or equivalent. While there may be a short break in period seating the pad to the rotor and wearing any high spots off the pads, excessive heat and evident pad dust in any quantity should not be occurring.

Later Ed

[Jeremy Parrett]

Ed,
 after the work was done in Indio.CA we drove east.   In Vicksburg Ms I noticed oil all over the wheels and frame so we had a new seal installed.  The new  brake pads installed in Indio were soaked in oil.  We cleaned them and reinstalled them.
  Could the hypoid gear oil have affected the pads??

[Marty and Suzie Schenck]

Jeremy, On mine, the pads did not retract for what ever reason (pads stuck, calipers stuck or calipers cock-eyed on pins) which caused friction on the rotors that cooked the seal in the rotor that allowed gear oil to spray everywhere. You need to be sure that as ED said, clay based grease was used in the calipers and the caliper pins were assembled dry, no lube at all. You also need to be sure that the pre set brake adjustment is performed as prescribed  per Meritor. I would also change out the oil soaked pads. Marty

[Edward Buker]

Jeremy,

I'm not sure if an oil soaked pad is recoverable with cleaning. Maybe Gerald could answer that but I have no experience. I do not think that oil in the pad is causing the heating or the lack of a good release of the pad pressure on the rotor. That needs some sorting out unless you think it is resolved. I know of a shop in Robertsdale AL that has some experience. There must be good shops out there but they have to have Meritor experience I would guess.

Later Ed

[Gerald Farris]

Jeremy,
I do not think that the oil soaked pads are your problem as most of the pads that fit the ADB brakes are made of a ceramic material that is not porous enough to retain the oil. However, a through inspection is needed to determine the cause and any speculation here is just that, speculation. The pads are making excess contact with the rotors and therefore the heat buildup. So you just need to determine why.

Gerald 

[Jeremy Parrett]

Thanks Gerald.   Pretty sure its the calipers not sliding on the pins.  They were cleaned up pretty well and re installed with the new pads and rotor .    Will pick up 2 cartridges on our way west at Covington Heavy Duty Parts in Pensacola Fl. next Monday.  I understand I can use the clay based grease in the calipers and the slack adjusters.

[Edward Buker]

Jeremy,

That is where I have purchased the Meritor grease also. I use it just in the caliper fittings and use EP2 quality chassis grease in the slack adjusters. That is easier given the slack adjusters get greased with the chassis and I may go 3 years before I would do the caliper fittings. The slack adjusters do not get hot so you do not have the same issue as the caliper. The procedure needs to be followed given the excess grease has to be purged out.

Later Ed

[Jeremy Parrett]

ED,
  just figured using clay based Meritor grease only for both caliper and slack adjuster will reduce/eliminate the risk of a mechanic using the wrong grease.

[Edward Buker]

Jeremy,

You can use either type grease in the slack adjuster but it is probably not good to go back and forth, so if you are going with clay based grease just keep using it. I am not convinced that your brake issue is a grease based issue with the caliper. Hope you can get it looked at and diagnosed soon, better not to have to worry.

Later Ed

[Jeremy Parrett]

ED,
  I agree.  I will get the brakes looked at asap.  Only a short 10 mile drive today changing RV Parks but I did not see any evidence of brake dust or smell after we parked.  I also noticed the coach free wheels if I let the brakes off waiting at traffic lights in neutral.
  The trip to Pensacola Fl on Monday will be a better test. 

[Gorde Lang]

Since starting this discussion on disc air brakes overheating on rear driver's side,2000Beaver marquis tourmaline l backed off slack adjuster & drove coach 50 miles to Sacramento Truck center without incident. Service manager crawled underneath & said there was evidence of heat build up &residue .He mentioned something about seeing a slight gap where pin goes through  brass insert. He said a lot of shops don't change them due to being a pain in the.....He also commented that the calipers hadn't been changed and having 100000 miles on coach would cost in the $900.a piece range. When he pulls the wheels on Tuesday the 5th he will know more. This coach was just serviced at bcs _ 550 miles ago, specifically this brake problem. Im hopefully going to hear from ken at bcs, it'll be 8 days tomorrow since my email to him. Im worried