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General Boards => Technical Support => Topic started by: Gorde Lang on December 29, 2015, 05:55:52 PM

Title: disc break air help
Post by: Gorde Lang on December 29, 2015, 05:55:52 PM
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
Title: Re: disc break air help
Post by: Steve Huber on December 29, 2015, 06:50:29 PM
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
Title: Re: disc break air help
Post by: Jeremy Parrett on December 31, 2015, 01:11:06 AM
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.
Title: Re: disc break air help
Post by: Joel Ashley on December 31, 2015, 02:12:11 AM
Gorde, I hope you called BCS about this.

Joel

Title: Re: disc break air help
Post by: Edward Buker on December 31, 2015, 04:38:17 AM
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
Title: Re: disc break air help
Post by: Jeremy Parrett on December 31, 2015, 04:23:02 PM
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??
Title: Re: disc break air help
Post by: Marty and Suzie Schenck on December 31, 2015, 05:05:30 PM
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
Title: Re: disc break air help
Post by: Edward Buker on January 01, 2016, 12:57:14 AM
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
Title: Re: disc break air help
Post by: Gerald Farris on January 01, 2016, 03:19:03 PM
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 
Title: Re: disc break air help
Post by: Jeremy Parrett on January 01, 2016, 10:10:43 PM
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.
Title: Re: disc break air help
Post by: Edward Buker on January 02, 2016, 12:40:02 AM
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
Title: Re: disc break air help
Post by: Jeremy Parrett on January 02, 2016, 12:59:56 AM
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.
Title: Re: disc break air help
Post by: Edward Buker on January 02, 2016, 01:19:23 AM
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
Title: Re: disc break air help
Post by: Jeremy Parrett on January 02, 2016, 01:32:14 AM
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. 
Title: Re: disc break air help
Post by: Gorde Lang on January 04, 2016, 03:51:16 AM
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
Title: Re: disc break air help
Post by: Joel Ashley on January 04, 2016, 10:12:17 PM
This is not something you can put any reliance on an email about.  They don't always get read and often are auto-displaced by system settings to the junk file before the recipient sees them.  I've sent emails to Ken before without response.  Same thing happens with emails to my Ford dealer service advisor.

That's usually not the case with a phone call.

Joel
Title: Re: disc break air help
Post by: Jeremy Parrett on January 05, 2016, 01:19:11 AM
Pretty sure this caliper overheating was caused by the wrong grease being used.  When the rotor was replaced with new pads and a new oil seal  we cleaned the caliper pins and reinstalled the caliper.  I suppose the old grease is still in the caliper.
  How much clay based grease do I put in one caliper to be sure I have purged the bad grease out?????
  Will be at Covington Heavy Duty Parts in Pensacola Fl tomorrow morning.
Title: Re: disc break air help
Post by: Edward Buker on January 05, 2016, 03:28:56 AM
Jeremy,

I think you will use about a third of a  tube to purge the old grease out.....that is a guess. The clay based grease is a light tan color so you should see a color change or fresh grease emerge. The older grease, even if the same type will probably have darkened some.

It is important that the lube procedure be followed. It is on pages 52 and 53 (numbers on the pages) of the Meritor Brake manual that details the procedure. There is an adjustment to set the inboard pad against the rotor using the slack adjuster, a pressure relief valve is removed and you grease the caliper grease fitting, then the slack adjuster is used to move the caliper piston fully in the opposite direction to purge excess grease out of the pressure relief valve hole. Then you wipe the excess grease and put the pressure relief valve in and adjust the slack adjuster to spec. There are diagrams that point to the proper grease fitting etc.

Basically you are filling the chamber with grease and with movement of the piston travel using the slack adjuster, purging enough grease to allow for expansion, so that the piston is not forced into the rotor due to grease expansion. Whether you do it or have a shop do it, make sure they have that procedure. If you search on Meritor Brakes you should find the manual. I thing Monaco did a document with the same info. Hope this helps.

Later Ed
Title: Re: disc break air help
Post by: Jeremy Parrett on January 05, 2016, 01:59:41 PM
Ed,
  great information.  Many thanks.  I assume 1/3 rd 0f a tube will do both drive axle calipers.   Therefore 2 tubes will be enough to do all 6 calipers.
             We are heading to Covington HD Parts today and then to Quartzsite AZ.   Best wishes.  The BGB Crew !!  ( Big Green Bus) 
Title: Re: disc break air help
Post by: Jeremy Parrett on January 06, 2016, 02:25:15 AM
FYI    Meritor Clay Based Grease per tube  $14.   I bought the 4 tubes  Covington HD Truck Parts  had in stock.
Title: Re: disc break air help
Post by: Jeremy Parrett on January 09, 2016, 04:20:05 AM
Left Florida east coast Monday Jan 4th  and arrived Blythe CA today Friday Jan 8th  .  No evidence of overheated brakes.  Hopefully someone at Quartzsite will be able to check things out.
Title: Re: disc break air help
Post by: Adam Hicklin on January 21, 2016, 07:11:41 AM
To clear up my own confusion about grease.  The meritor manual calls out 2 different types of grease for the caliper: 0-616-A which I'm guessing is the standard clay-based grease, and 0-645 which is a synthetic, the best as I can figure it.  I never hear anyone talk about the 0-645.  Am I reading something wrong?
Title: Re: disc break air help
Post by: Edward Buker on January 21, 2016, 05:52:57 PM
Adam,

Not absolutely sure of this, but in the manual they say that the fittings beyond where they require the clay based grease, like the slack adjusters, can use non clay based grease given they do not have the heat issues. I have gone to a quality chassis grease for the slack adjusters for instance. If they are not calling for that synthetic grease specifically at certain fittings then I think this is the reason behind mentioning the second grease. Of course they will give you their product number given they want to sell it.

Later Ed
Title: Re: disc break air help
Post by: Adam Hicklin on January 22, 2016, 04:50:04 AM
This is from the Meritor 4M manual:
Could I be looking at the wrong thing?  Wrong manual?
Title: Re: disc break air help
Post by: Edward Buker on January 22, 2016, 03:06:42 PM
Adam,

That table indicates that they have two versions of the clay based grease, one is synthetic, and that either of those two PNs can be used in the caliper fittings. It also shows that there are more options for greasing the slack adjusters which includes a lithium based grease which is your typical high quality chassis grease. Because you are not supposed to mix clay based and lithium grease I have been using lithium based Chevron NLG2 grease on the slack adjusters and the chassis fittings but not the calipers. Over several greasing's I have purged the clay based grease out on the slack adjusters. If you get your chassis greased at a shop while on the road they are likely to always grease the slack adjusters so I have moved away from clay based grease for those fittings.

You need to be sure that whoever is greasing the chassis understands that they are not to do the caliper grease fittings with chassis grease. I would supply them a page from the brake manual that shows the caliper fittings with a big red circle on it and a note not to grease those fittings as part of the chassis lube. It may be worth getting under the coach with them and pointing them out to whoever is greasing the chassis if there is any confusion. Hope this helps.

Later Ed
Title: Re: disc break air help
Post by: Gorde Lang on January 26, 2016, 06:23:57 PM
After taking my brake problem to sacremento truck center after overhauling this very same brake problem, the new pins passing through the honed out bushings were loose.Sacramento Truck would not warranty nor rebuild old parts.After changing into the new calipers we have been trouble free from sacremento to Arizona &back to Vallejo, California. This was an additional $2400.to bcs repair bill.We did get our first & terrific trip in to quartzite Arizona, wonderful beaver owners &friends
Title: Re: disc break air help
Post by: John Fearnow on February 23, 2016, 02:56:06 AM
Gorde,
I am dealing with the same caliper issues you are and have sent you a pm asking for additional info concerning replacement parts.

Thanks
John Fearnow
2002 Patriot-Thunder
Title: Re: disc break air help
Post by: Eric Wallace on April 07, 2016, 12:05:41 AM
Ed Buker, in reply number 10 above, you say "The procedure needs to be followed given the excess grease has to be purged out." 
Where can I find the procedure for doing this work?  I believe my 2001 Monterey 33' coach has the Meritor brake system. 
Title: Re: disc break air help
Post by: Eric Wallace on April 07, 2016, 12:14:33 AM
Ooops... I just noticed there was a second page on this brake topic.  I see that certain pages of a Meritor Brake Manual are referenced, but when I do a web search many, many Meritor manuals come up.  One I randomly chose did not even have a page 52-53.  Does anyone have the link for the appropriate one for our systems?  Thanks.
Title: Re: disc break air help
Post by: Gerald Farris on April 07, 2016, 05:39:54 PM
Eric,
Your 2001 Monterey does not have the Meritor ADB brake system that is being referred to in this post. The 2001 Monterey has hydraulic brakes that use air pressure for assist in the same manner that vacuum is used for the power brake assist on your car.

Gerald 
Title: Re: disc break air help
Post by: LaMonte Monnell on April 07, 2016, 10:03:38 PM
Eric,
Your 2001 Monterey does not have the Meritor ADB brake system that is being referred to in this post. The 2001 Monterey has hydraulic brakes that use air pressure for assist in the same manner that vacuum is used for the power brake assist on your car.

Gerald
I guess my 2001 Contessa would not have the meritor brakes either then.
Title: Re: disc break air help
Post by: Jerry Emert on June 12, 2016, 03:04:42 AM
When I was in Texas the gentleman I had working on my air suspension (travel mode) noticed that the drive shaft needed to be lubed as did the slack adjusters.  I had just had it done at Eagle's Pride in Titusville Fl.  Somewhat disappointed in them!  Anyway, he did the lubes and I mentioned the clay based grease I've read about in the past.  I've noticed on this thread that the clay doesn't apply to slack adjusters.  Does it apply to the drum type brakes in my Patriot as it does with y'all that have disk brakes?
Thanks
Jerry
Title: Re: disc break air help
Post by: Gerald Farris on June 18, 2016, 07:42:00 PM
Jerry,
The clay based grease that has been mentioned on this Forum, is used to lubricate the brake calipers only (not slack adjusters) on coaches that are equipped with Meritor ADB brakes (air disc brakes). The only Beaver coaches that are equipped with the Meritor ADB brakes are the Marquis from mid 1998 (start of Magnum chassis production for Marquis) through 2002, and the 2002 Patriot Thunder.

Gerald