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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Jim Blackwood on May 31, 2020, 04:26:21 PM

Title: Where did they hide the air lines?
Post by: Jim Blackwood on May 31, 2020, 04:26:21 PM
For the main airbags on the MCI DL, I guess you have to drop the bag to get to the top fitting but where does the line come out? I haven't spotted it yet. Seems like there would have to be 4 of them.

Jim
Title: Re: Where did they hide the air lines?
Post by: thomasinnv on May 31, 2020, 07:10:27 PM
Quote from: Jim Blackwood on May 31, 2020, 04:26:21 PM
For the main airbags on the MCI DL, I guess you have to drop the bag to get to the top fitting but where does the line come out? I haven't spotted it yet. Seems like there would have to be 4 of them.

Jim

I'm assuming you are referring to the drive axle, as the steer and tag axles are both open and accessible above the airbags. Unless you plan on cutting a hole through the floor above,  you need to remove the airbags and then unbolt the upper mounting plates to access the airlines. Unless you have a leak that you are trying to rectify there really is no reason to have to do this. If you are just looking for a point to tie into the airbags for levelling purposes this can be done at the valves which are mounted right above the drive axle, easy access.
Title: Re: Where did they hide the air lines?
Post by: Jim Blackwood on June 01, 2020, 08:52:42 AM
Thank you, I thought as much. Can you tell me where the lines come out of the structure though? It's not so easy to spot looking past the tires.

Jim
Title: Re: Where did they hide the air lines?
Post by: thomasinnv on June 01, 2020, 10:32:59 AM
Been a while since I've been under there but I believe the airline enters the floor pan just inboard from the airbag mounting plate. If you're looking for somewhere to tie into the existing line, the best place to do so would be the output side of the ride height valves. Each rear ride height valve on the DL3 controls the bags on the drive axle AS WELL as the tag axle bags.
Title: Re: Where did they hide the air lines?
Post by: buswarrior on June 01, 2020, 11:35:35 AM
Yvan LaCroix has pics of the top of the bags, from above, with the floor torn out.

Facebook presence, LaCroix Cruiser

Be warned, the original converter tore the hell out of that coach, so what you see now that Yvan and Sylvie have torn it back out to the frames, is not what is behind the walls in yours...

Happy coaching!
Buswarrior
Title: Re: Where did they hide the air lines?
Post by: Jim Blackwood on June 01, 2020, 12:26:34 PM
OK. I;m waiting on HF to put their 12 or 20 ton air/oil jacks and 12 ton jackstands on sale again. The rear lift option gets it high enough to get the jacks under it and those and the jack stands should get it high enough to get in there I think. So the back end may take awhile. Got parts o/o for the front. Found a push connect servo that will make it very easy if it doesn't leak.

If the leveling valve handles both drive and tag I don't really see a simple way to deal with that end other than disconnecting the link arm and using it somehow. I know it will exhaust the air all the way down to zero, it's sitting there like that now with the blocks between the middle air bag mount and the frame. I also know the PPV valve limits max pressure to 90 psi (at least I think so) for the rear lift. So the easy solution may include bumping that up to max. I'll know more once I get into it, but I'll start a new thread for that or go back to the other one and continue.

Jim
Title: Re: Where did they hide the air lines?
Post by: thomasinnv on June 01, 2020, 12:42:43 PM
I would suggest that for the purpose of levelling the coach that you keep the tag bag connected to the drive axle bags. There is a lot of weight on the back end of the DL3 and having all 3 bags on either side working in unison in my opinion is the best solution. If you isolate the tag axle bags it would require much higher air pressure to achieve the same height. I have air levelling on my DL3 and I would not do it any differently. You can easily control each side by tying into the existing airline on the output side of the ride height valve. Use a solenoid valve to shut off the airline from the ride height valve when using manual levelling.
Title: Re: Where did they hide the air lines?
Post by: Jim Blackwood on June 01, 2020, 12:48:36 PM
Derrick, did you do the leveling system or did someone else?
If someone else, do you know how they tied into the existing system?  (If it was you I have some kinda technical questions I'd like to ask.)

Jim