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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: MattC on March 02, 2009, 08:10:09 AM

Title: Pneumatics
Post by: MattC on March 02, 2009, 08:10:09 AM
The pneumatics on my coach opens and closes the door just slightly slower than the speed of sound.  No joke, scares me every time I use the blanked blank thing.  It jerks open and oscillates for a couple seconds from the force, and closes with a bone shattering WHAM!

I normally throw the over-ride and manually open and close the door.

Any suggestions?  I'm considering finding an old manual lever system and installing it.  LoL
Title: Re: Pneumatics
Post by: luvrbus on March 02, 2009, 08:37:30 AM
Matt, install a pressure regulator on the supply line past the valve work for Kevin on his MCI   
GOOD LUCK
Title: Re: Pneumatics
Post by: TomC on March 02, 2009, 08:43:48 AM
The problem with a pressure regulator is that if the air pressure holds the door shut (as is the case on many buses) the lower pressure will not be enough.  Instead put a flow restricter valve in (a simple ball valve would work). Then you can adjust it to the speed which the door opens and closes, but still creates full air pressure to hold the door shut.  If the door holding close is not a feature, then the pressure regulator would work best-keeping full pressure out of the system completely.  Two choices now.  Good Luck, TomC
Title: Re: Pneumatics
Post by: JackConrad on March 02, 2009, 08:46:35 AM
On a 102A3 that I removed the air closer on, it required filling a chamber with antifreeze (this is up under the dash). The liquid served as a buffer slowing down the action. When the fluid leaked out, the door would KO anybody standing in front of it when it was opened.  Jack
Title: Re: Pneumatics
Post by: luvrbus on March 02, 2009, 08:51:20 AM
40lbs shuts the door easy and will hold it shut does on his anyway the cylinder mechanism breaks over center and take very little to keep it close like Jack said check the antifreeze in the cylinder but if it is wore out the fluid will bypass and have no effect on slowing the door  good luck
Title: Re: Pneumatics
Post by: Jerry32 on March 02, 2009, 09:01:19 AM
I believe the cylinder has an adjustment to change the rate too.
Title: Re: Pneumatics
Post by: Blacksheep on March 02, 2009, 09:13:34 AM
Mine has an adjustable thumb screw that allows you to speed up or slow down the opening and closing of the door!
Yours could be similar!

Ace
Title: Re: Pneumatics
Post by: lostagain on March 02, 2009, 11:40:33 AM
Check your manual. There is a procedure to purge the operating cylinder. I did just that a couple month ago on the hockey team's 102D3. It is not hard to do, and will return the door operation to normal.

JC
Title: Re: Pneumatics
Post by: John316 on March 02, 2009, 01:30:16 PM
I will guess that your antifreeze is non-existent. Our door did the exact same thing until we filled it up. I can go more in depth about how the door works if you want...

If not I won't make you sleepy ;).

God bless,

John
Title: Re: Pneumatics
Post by: MattC on March 02, 2009, 03:31:14 PM
Quote from: John316 on March 02, 2009, 01:30:16 PM
I will guess that your antifreeze is non-existent. Our door did the exact same thing until we filled it up. I can go more in depth about how the door works if you want...

If not I won't make you sleepy ;).

God bless,

John

John,

I would like the details, I looked at mine and didn't see a reservoir under the dash, however I'd probably not recognize it if it bit me.

Thanks!

Here is a pic of my mess.  =)
Title: Re: Pneumatics
Post by: lostagain on March 02, 2009, 09:12:41 PM
MattC, looks like mine on the D model. I could scan the page off the manual and email it to you if you want.

Or call MCI tech support, they will fax you a copy of the instructions if you ask.

JC
Title: Re: Pneumatics
Post by: JackConrad on March 03, 2009, 05:16:12 AM
Matt,
   I think the antifreeze goes in the long cylindrical thing in the picture.  I don't remember exactly where or how much.  Jack