air door latch on mci 9

[platinum mci]

 I have the 1984 mci 9 with a single door not the bifold and was trying to figure out how the air latch on the entry door works any tips on this would help a lot.

[bottomacher]

It is a simple latch that grabs a hook on the door, air actuated and interlocked with the door closer handle on the dash, subject to the override valve below the dash. Are you looking to troubleshoot one that doesn't work?

[platinum mci]

it looks like now I need trouble shooting advice when I move the overrule lever under the dash the lock arm does nothing I believe the only thing that holds the door closed when driving is the manual lever to open and close the door.

[chvyman]

I am thinking of getting a 12 volt linear actuator in place of the pneumatic to lock the door rather than put a latch or a dead bolt put a toggle switch inside the coach and put a key lock right there by the handle to operate the actuator from outside the coach. And have a pneumatic cylinder to operate the door with an orifice to keep it from slamming open and same when closing.

[jmblake]

Platinum
On my 81 MCI9 the latch only works when the maxi brake is released & the door shut. There is a switch up under the dash where your dash door handle hits when the door is in the closed position, I'am going to rewire it to a switch and air selinoid to lock it manually. Jason

[Jriddle]

Platinum
I have same problem on my 9 also. Thanks for your post maybe we will learn something new today as I have not looked into fixing mine yet. I didn't know how it worked and now I do.

John

[Airbag]

Well I don't feel so bad now my MC-5A door catch works but only with the cherry valve. I looked at the handle area where the electrical switch is supposed to be and damn near threw up when I saw what a cobbled flucking mess it is in there. My system has no hope of ever working with the door handle so I use it manually and I need to install a dead bolt type of door handle for when we are parked. Best of luck to all with this MCI problem and I hope yours has never seen the idiot mechanic that ruined mine

[platinum mci]

Well thanks for the great advice I had not tried the valve with the parking brake pushed in so I will try that, but what if you want to shut the door and your parked what does that buttom on the fromt of the bus in the middle do I thought it was to unlock the door?

[jmblake]

On mine the button just unlathed the handle on the dash it had nothing to do with the air lock.

[buswarrior]

The mechanical door handle linkage is an over-centre type affair. The button on the front of the bus gives the over-centre mechanism a push over the centre so the door will be able to be pulled open.

Assuming that everything is properly adjusted and not worn out....

The air latch control is acted upon up under the dash by the mechanical door handle linkage, if it is properly adjusted and all the metal that these things attaches to isn't rotted away....

The release valve under the dash above the accelerator at the driver's right knee will release the air pressure from the air lock circuit, upstream of all the above, think of it as the supply valve.

It does take a bit of fooling around to get it all just right, that the door can be gently closed without locking, that the door may be slammed to lock, that the door handle doesn't require two hands and a foot on the dash to get past the over-centre, and for the air lock to work as intended.

Whether you get it to work with your door closing handle, or not, you do need some sort of strong latching method, as the door gets sucked open quite strongly at highway speed by the slipstream.

happy coaching!
buswarrior

[platinum mci]

wow thank you for all the help I just went and tried it and sure enough if you push in the park brake the air lock engages I haven't tried slamming the door from the outside to see if the knob will unlock it will have to get somebody inside just in case it does not work.

[Jriddle]

That is what I like about the people on this board. I can figure most things out on my own. I know the air latch wasn't working but is low priority as I'm working on other things. I figured when the day came I would look into why it wasn't functioning. Now when time comes I will have some kind of idea where to start. THANKS.

John

[Paul]

There is also a manual release for either air door located in the front junction box.

Paul

[platinum mci]

i'm very new to this bus where's the front junction box located?

[Paul]

Front junction is under the drivers window outside of the bus. Release is on top left side. This choke type cable will pull or move the air dump valve located below the right corner of the instrument panel in the bus. With the air dumped to the door, the door may opened or closed by hand.


      Paul