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Kat Battersby (Ramblinruby)
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Username: Ramblinruby

Post Number: 14
Registered: 5-2009
Posted From: 168.103.122.174

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Posted on Tuesday, June 15, 2010 - 10:03 pm:   

Hi All,

I got my 4106 started today and after about 5 minutes my engine just quit. Something activated my engine kill switch and I was wondering if any of you all could give me some feedback on what might have activated it and how I can deactivate it.

Thanks,
Kat
marvin pack (Gomer)
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Username: Gomer

Post Number: 931
Registered: 3-2007
Posted From: 71.55.3.249


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Posted on Tuesday, June 15, 2010 - 10:30 pm:   

Kat; the kill switch is operated by air pressure and sometimes the air solonoid becomes sticky and doesn't operate properly. keep trying to keep it running and check the air pressure and you will see how it operates. Air builds up,and when you shut the master switch off it activates the solonoid that releases air to the valve on the governer. It also may be electrical.

Gomer
Kat Battersby (Ramblinruby)
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Username: Ramblinruby

Post Number: 15
Registered: 5-2009
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Posted on Tuesday, June 15, 2010 - 10:54 pm:   

Hi Gomer,

How can I reset the switch so I can try to start it again? The switch is keeping me from starting again.

Thanks,
Kat
George M. Todd (George_todd)
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Username: George_todd

Post Number: 1034
Registered: 8-2006
Posted From: 99.184.9.29

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Posted on Tuesday, June 15, 2010 - 11:00 pm:   

Kat,

The rear run switch may be in the stop position.
The way all of our vintage buses work, is that it takes air pressure to move the governor stop lever to the stop position. When you start your bus with no air pressure, the engine will idle for about 5 minutes before enough air pressure builds up to push the stop cylinder out. All of our buses require electricity to keep the Skinner valve closed so no air gets to the shutdown cylinder. When you turn the master switch off, no electricity, so the Skinner valve lets air (if there is any) to the shutdown cylinder, and the engine stops.
G
George M. Todd (George_todd)
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Username: George_todd

Post Number: 1035
Registered: 8-2006
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Posted on Tuesday, June 15, 2010 - 11:49 pm:   

Kat,

Was typing while you posted, so read mine above, but keep in mind that a "kill" switch doesn't exist. Your problem is a loose electrical connection, either in the ignition circuit, or a loose ground.
G
FAST FRED (Fast_fred)
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Username: Fast_fred

Post Number: 1207
Registered: 10-2006
Posted From: 99.155.204.111


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Posted on Wednesday, June 16, 2010 - 7:10 am:   

There are 2 ways to kill the 8v. The solenoid on the gov is one .

The other is the flap valve in the blower feed.

Is this what you meant by Kill switch?

The flap MUST be hand reset if triggered.

BY DA BOOK!!!!

FF
Kat Battersby (Ramblinruby)
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Username: Ramblinruby

Post Number: 16
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Posted on Wednesday, June 16, 2010 - 9:06 am:   

Hi FF,

Ok, It's that valve that sits on top of the governor. It's always been open but now that little rod has shot out and closed that circuit off. How do I reset that?

Thanks,
Kat
Dave Walker (Chrome_dome)
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Username: Chrome_dome

Post Number: 49
Registered: 3-2010
Posted From: 67.174.144.159


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Posted on Wednesday, June 16, 2010 - 10:12 am:   

Make sure you red cover switch is not thrown if so reset it front and back. Make sure your rear switch is in the front start position.

The air flap trigger that Fred was talking about is on the rear upper right side of the motor. there is a little sticky outy thing (small 1/4" rod). Just above the Valve cover end. You push it down until it clicks and holds in place. Then start it up and stop hitting the kill Master. 2 Things are problems of no starts, Fuel or air and your probably was not getting any AIR.

Dave

(Message edited by chrome dome on June 16, 2010)
Jack Conrad (Jackconrad)
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Username: Jackconrad

Post Number: 1305
Registered: 12-2000
Posted From: 173.151.192.184


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Posted on Wednesday, June 16, 2010 - 11:42 am:   

That "thingy" on top of the govenor is the normal engine stop piston. Their is an electrically controlled solenoid valve that allows air to push the piston out to stop the engine (shuts off fuel supply). You can remove one of the screws on the piston assembly and turn it it so the piston misses the lever that it normally contacts or disconnect and plug the air line. More than likely you have a solenoid that is sticking or a solenoid electrical problem. Do you have a manual with the elecvtrical schematics? Jack
George M. Todd (George_todd)
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Username: George_todd

Post Number: 1036
Registered: 8-2006
Posted From: 99.184.9.29

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Posted on Wednesday, June 16, 2010 - 8:05 pm:   

Kat,

We need some clarification, does your bus now crank but not start? Or does it not crank at all?

The shutdown flapper which Fred describes will stop a runaway engine from a stuck injector, or from running in a combustible atmosphere, but will not prevent the starter from cranking the engine.

The small rod which you describe is the normal shutdown piston/cylinder, which extends to stop the engine. As I detailed above, it is operated by air pressure, and controlled thru a solenoid valve called a "Skinner valve." This valve is referred to as NORMALLY OPEN, in other words, air passes thru it when no power is applied to it. When it has power, no air flows thru it to the stop cylinder, which stays retracted.

The master switch controls power to the Skinner valve, AND to the start switch, so an electrical open circuit, (a loose wire or connection) will cause the Skinner valve to allow air thru to the stop cyl, and not allow power to the start switch.

If the rear control switch is in the stop position, the bus will probably start from the front, then die when enough air pressure builds to operate the stop cyl.
G

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