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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: mikelutestanski on May 21, 2014, 08:27:44 AM

Title: rolling lobe replacement for mci 7
Post by: mikelutestanski on May 21, 2014, 08:27:44 AM
Hello    Anyone who has changed their air bags for rolling lobe have any trouble lining things up??
    I bought the kit from mci  and things are interesting.  i did the drilling as accurately as required but the bags are not in the right position for the bottom bolts.   I can twist the bottom but I don't want to destroy the integrity or life of  the bag.   I can extend the holes or red rill but that does not seem right either
    These bags have a nut on the bottom possibly holding the bag in place.  (Not sure) .   Will that allow the bottom to twist?     
     Any help would be appreciated.  I would hate to put the old bag back on..
           Trying to get ready for our east coast trip this year.  heading up the coast across to niagara , then canada across to michigan.   
           update!    Update!!  Talked to MCI technical support.  The man said I could stretch the bag and when it releases from the bottom plate it can be rotated. (two people required)   I don't know if I can do it   maybe with a jig to hold it in place..   He further suggested if I hooked it up to the axle then removed the shock and carefully let the bag down it should straighten.  One of the problems with that is I probably have to do the whole axle at once .. 

       AHHHH the joys of owning a bus..     
        Regards  and happy bussing  mike   
Title: Re: rolling lobe replacement for mci 7
Post by: TomC on May 21, 2014, 12:41:31 PM
While it doesn't sound right, a rolling lobe doesn't need to be aligned perfectly. I've seen many a truck with the air bags off kilter going down the road. Good Luck, TomC
Title: Re: rolling lobe replacement for mci 7
Post by: Lin on May 21, 2014, 12:44:21 PM
What is the reason for switching to a rolling lobe bag?
Title: Re: rolling lobe replacement for mci 7
Post by: Rick 74 MC-8 on May 21, 2014, 03:26:15 PM
I changed mine out last year I had no problems at all everything lined up no holes to be drilled or anything got the kiT  ds from Mohawk


Rick 74 Mc-8
Title: Re: rolling lobe replacement for mci 7
Post by: wg4t50 on May 21, 2014, 04:45:07 PM
Agree, I also replaced those bags on the tag axle, do not recall any issues, sure no drilling, just new bags and new hose, most likely the most econo thing about the MC7.  I total rebuilt mine started in 1988 and never had an issue on the road, it always brought me home with no problems, 3 different engines, 2 transmissions, new 3rd member, all new front end suspension, all bearings, brakes, slack adjusters, S cams, brake chambers, no end, just total rebuilt from windshield wiper shaft bushings to tail pipe, loved every minute of it.  Had the shop, tools and equipment to play in a man size sand box.
Dave M
Title: Re: rolling lobe replacement for mci 7
Post by: jmblake on May 21, 2014, 04:54:46 PM
Mike, When I changed my old DBL lobe bag to the rolling lobe I had to loosen the big nut on the bottom and turn the base to match the new holes you have to drill, 2 people make it easier but once you do one the rest are a little easier.
Jason
Title: Re: rolling lobe replacement for mci 7
Post by: mikelutestanski on May 21, 2014, 06:18:50 PM
  Thanks for the comments and tips..

hello   update,     I guess i did not make it clear this is the rear axle.   The front I did with mohawks bags several years ago.  I did not like the bags however they are still on the front.  I decided to go with mci for the rear even tho they are pricier.  
   I leveled the bus today (raised the front so that the bus is level with 12 inch blocks under the rear posts)  and things are looking better however not completely out of the woods yet.  With some prying the bags tend to move a bit. I still have 2 bags with some side issues.   One fellow said I would have to replace shocks also..  WE will test drive when completed.
    I did have some issues with leaky bags and trouble trying to seal the bottom plates due to rusting. The top is all blocking plates installed in 1997.    I changed a bag in2005 and had trouble with the bag and sealing the bag.   SO this time I decided to give these a shot.Before I started I identified another leaking on the bottom.  SO I decided to replace all of the bags
  Florida is not kind to rubber or batteries.  The heat and humidity shortens life of these items..
..  I don't believe the ride will change much.  WE need peace whilst traveling so 'i try to take care of issues and check.   I do have some air leaks because the front gage will not hold for more than an hour but everything i have soap tested has passed.  I am especially critical of the  brake system.  SO far that is not the problem..  
     regards   mike

    Latest update friday noon   Still have issues sideways.  Has to move the bottom sideways about half an inch to get bolt started   .  I got it on and the other side down but the bag is not hanging straight.  Has a slight twist. Well back to the drawing board.  I may have to reinstall the old bags if the axle and beam plates have out of square issues..  oh life on  the bus lane..      happy holiday and thanks to those who served..  regards   mike 
     
Title: Re: rolling lobe replacement for mci 7
Post by: mikelutestanski on May 29, 2014, 06:11:54 PM
Hello   Job done and successful..    My problem was not keeping the axle up tight and level..  If you let one side down more than the other  then things are off level..  I had to expand some of the holes from 9/16 to 5/8 especially the air fitting hole..
      Bags are in proper position .. I am running 45 psi on one side and 50 on the other using the  bus leveling valves . I have Pete Pappas' system installed and it works well. 3 point leveling.   
Made a 10 mile test drive  and all seems well.   june 1 we will head to jetty park ,cape canaveral for a 125 mile run.

  If I had to start over  I would drill a small pilot hole and use the plasma cutter for the actual hole forming..Drilling with a right angle drill was too tedious.  The air fittings provide need a very accurate fit to seal properly.
       The important lesson learned is to keep track of where the axle is and keep it level..  whilst installing and working the new bags.   regards   and happy bussing  mike