Author Topic: Testing the door claw  (Read 577 times)

Offline Jcparmley

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Testing the door claw
« on: December 06, 2018, 11:31:03 AM »
Does anyone know how to test the door claw on a mci102c3? I don't think mine is working.  I have never seen it work. 

Offline lostagain

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Re: Testing the door claw
« Reply #1 on: December 06, 2018, 11:50:23 AM »
With ignition on and air above 90 psi, you can open and close it with the red button under the dash that is the emergency door  overrule opener/unlocker.

JC
JC
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1977 MC5C, 6V92/HT740

Offline buswarrior

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Re: Testing the door claw
« Reply #2 on: December 06, 2018, 12:47:51 PM »
To clarify, the door handle/arm has to be closed to satisfy the circuit.

The claw will not usually operate with the door open.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area

Offline Jcparmley

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Re: Testing the door claw
« Reply #3 on: December 06, 2018, 04:16:23 PM »
Yes, the door is shut.  I do not see the claw engage.  I was wondering if there was a way to manually operate the claw to see if it is working or moving freely. 


To clarify, the door handle/arm has to be closed to satisfy the circuit.

The claw will not usually operate with the door open.

Happy coaching!
Buswarrior

Offline buswarrior

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Re: Testing the door claw
« Reply #4 on: December 06, 2018, 04:59:02 PM »
The air cylinder has a strong return spring in it, you won't readily get enough leverage.

First, crack the airline on the emergency release to be sure you have air pressure up to that point, then you have to follow the airline to the activating valve on the door handle linkage.

Something behind the dash is out of alignment, broken or rusted off...

It "just works" whenever you click the handle in and out of the fully locked position.

Happy coaching!
Buswarrior

Frozen North, Greater Toronto Area

Offline lvmci

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Re: Testing the door claw
« Reply #5 on: December 06, 2018, 08:52:11 PM »
Hi Jcp, is your door open/close rocker switch to close? Red knob up? lvmci...
MCI 102C3 8V92, Allison HT740
Formally MCI5A 8V71 Allison MT643

Offline Jcparmley

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Re: Testing the door claw
« Reply #6 on: December 06, 2018, 09:01:08 PM »
Yes, it is in the up position and I make sure the door is closed as far as it will go with the dash switch. 

Hi Jcp, is your door open/close rocker switch to close? Red knob up? lvmci...

Offline scott332

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Re: Testing the door claw
« Reply #7 on: December 07, 2018, 05:48:40 AM »
On my MC-12 the if the transmission is in neutral the claw opens.  The door must be closed, knob under dash in the correct position, and transmission in gear to get it to operate. 
1992 MCI MC-12
1956 GMC PD4501-805

Offline buswarrior

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Re: Testing the door claw
« Reply #8 on: December 07, 2018, 07:22:59 AM »
GEEZ... the transmission interlocked... what a pain!!

What transmission is this?

Maybe a one off? The modern day MCI continue to have the air locks just be related to the door being fully closed.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area

Offline Jcparmley

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Re: Testing the door claw
« Reply #9 on: December 07, 2018, 08:19:58 AM »
I will check that today.  That would be interesting if that was it.  Thanks

On my MC-12 the if the transmission is in neutral the claw opens.  The door must be closed, knob under dash in the correct position, and transmission in gear to get it to operate.

Offline edvanland

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Re: Testing the door claw
« Reply #10 on: December 07, 2018, 08:56:11 AM »
On my MCI 7 I can hear it engage and actually see the door come in about a 1/4 inch.
Ed Van
MCI 7
Cornville, AZ

Offline jraynor

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Re: Testing the door claw
« Reply #11 on: December 13, 2018, 05:26:52 AM »
Have you figured it out?

If not, what type of door close handle do you have? mine was a pull down handle which I removed awhile back because I no longer wanted it after I got my door lock installed. There is a micro switch that the swing arm on the gear box (that converts the down motion into a left pull motion) closes which allows the circuit to work. So I believe that mine would operate regardless of it the transmission is in gear but I haven't paid much attention to it. But when I removed the gear box, of course it no longer worked. So I had to jump my switch so its always closed circuit and it works now. Eventually I'll wire in a door switch for when the door is closed but technically, its supposed to have one, I just haven't traced the wire to it yet nor have I actually been able to see a switch at the door frame.

Let me know where you're at with troubleshooting and I'll see what I can do to help
Jonathan
1986 TMC 102A3 6V92TA Currently Under Reno

Offline buswarrior

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Re: Testing the door claw
« Reply #12 on: December 13, 2018, 07:51:58 AM »
Having freshened up my door hardware knowledge last weekend on a friend's 102C3...

Find the micro-switch in the door linkage, it's buried way inside there, mounted on the far end of the activating piston body, and touched by a metal bracket mounted on the shaft that moves out to open the door.

My bet is the switch is either broken, or not being squeezed.

The one I worked on had 3 screws, and 4 wires attached. I did not bother to research what these 4 wires do, it was below freezing with a wind blowing, and we were on a mission, described further along...

To get the entire thing out, first, remove the bolt/pin at the output end of the shaft, ours needed two wrenches, with barely any room to turn 'em, but they do turn... then take out the pin at the back end, and the whole thing will carefully come out, butt end first, while all the lines and wires stay attached.

Our mission was to remove the cylinder's action from the door, so the door is easier to close when camping/engine shut off/air pressure absent. But, still keep the claw for keeping the door tight when driving.

After a little goofing with the multi-meter, we jumped the 2 single wires together on the centre screw, so the micro-switch thinks the door is properly closed all the time whenever the ignition is turned on. This bus will momentarily release the claw if either the dash switch, or the outside switch, is toggled to open. Owner liked it to do this. Easy to toggle and "lock" the door behind you as you exit.

Exhausting the air via the release with red knob under the dash is also an option.

With the ignition off, (and/or air pressure being down) the claw retracts.

We put the assembly back into place, re-attached the rear pin and left the bolt/pin from the far end of the shaft off, and tipped it up by putting a prop under it on that tray, so that it doesn't contact the linkage anymore, if it is toggled in error, a simple temp fix to an over-dampened door.

We were under time restraints, leaving it intact allows a return to function, if someone changes their mind, and/or the air and anti-freeze lines can be properly terminated at a later time, in a relaxed manner.

When a busnut is running south from the cold, the speedy, temp arrangements are very desirable...!

Unfortunately, I am left behind in the snow...

happy coaching!
buswarrior
Frozen North, Greater Toronto Area

Offline jraynor

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Re: Testing the door claw
« Reply #13 on: December 13, 2018, 04:39:38 PM »
Having freshened up my door hardware knowledge last weekend on a friend's 102C3...

Find the micro-switch in the door linkage, it's buried way inside there, mounted on the far end of the activating piston body, and touched by a metal bracket mounted on the shaft that moves out to open the door.

My bet is the switch is either broken, or not being squeezed.

The one I worked on had 3 screws, and 4 wires attached. I did not bother to research what these 4 wires do, it was below freezing with a wind blowing, and we were on a mission, described further along...

To get the entire thing out, first, remove the bolt/pin at the output end of the shaft, ours needed two wrenches, with barely any room to turn 'em, but they do turn... then take out the pin at the back end, and the whole thing will carefully come out, butt end first, while all the lines and wires stay attached.

Our mission was to remove the cylinder's action from the door, so the door is easier to close when camping/engine shut off/air pressure absent. But, still keep the claw for keeping the door tight when driving.

After a little goofing with the multi-meter, we jumped the 2 single wires together on the centre screw, so the micro-switch thinks the door is properly closed all the time whenever the ignition is turned on. This bus will momentarily release the claw if either the dash switch, or the outside switch, is toggled to open. Owner liked it to do this. Easy to toggle and "lock" the door behind you as you exit.

Exhausting the air via the release with red knob under the dash is also an option.

With the ignition off, (and/or air pressure being down) the claw retracts.

We put the assembly back into place, re-attached the rear pin and left the bolt/pin from the far end of the shaft off, and tipped it up by putting a prop under it on that tray, so that it doesn't contact the linkage anymore, if it is toggled in error, a simple temp fix to an over-dampened door.

We were under time restraints, leaving it intact allows a return to function, if someone changes their mind, and/or the air and anti-freeze lines can be properly terminated at a later time, in a relaxed manner.

When a busnut is running south from the cold, the speedy, temp arrangements are very desirable...!

Unfortunately, I am left behind in the snow...

happy coaching!
buswarrior

Yeah on my 102A3 it's a lot simpler. I don't have the outside buttons that I wish I did lol
Jonathan
1986 TMC 102A3 6V92TA Currently Under Reno

Offline buswarrior

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Re: Testing the door claw
« Reply #14 on: December 13, 2018, 04:46:57 PM »
The systems are all the same principle, powered or manual.

There's a microswitch that activates a pneumatic solenoid to power the claw.

The switch has to work, the switch has to be pushed, the wires have to be good, there needs to be air pressure, and a pneumatic solenoid that functions.

Get in there to get a visual on the microswitch.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area