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  #1  
Unread 03-02-06, 04:01 PM
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Roger Roger is offline
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Gear Doors Still Won't close

1980 H.

Quick overview:
Gear goes down fine, and all door close. Gear goes up fine but doors will not close BUT if you shut off the master once the gear is up, then turn the master back on, the doors will then close.

We have checked the switches on the mains. They are closed with the gear being held up buy pressure, and still closed when the master is turned off, pressure is released, and gear falls into the locks.

Nose gear is up, and switch is closed. However when the master is turned off the up lock releases and the nose gear falls. Then when you turn the master back on the nose gear goes back up, and this time all the doors close.

So I would assume that the issue here is that when the master switch is on with the gear handle up, there is pressure to the uplock on the nose gear. Then when the master is turned off, the presure is released from the nose uplock, which allows it to fall against the gear doors, should you have an electrical outage that requires you to hand pump the gear?

So the question is, why do the gear doors only close when you have first cycled the gear up, then with the gear selector still in the up position, you turn off the master, turn it back on, and the doors close.

The only other strange thing is that the Gear in transit light seems sporadic. Does that switch/circuit somehow direct the doors? If so, why then would it work after you release the pressure with the master, then hit it again.

Any help would be greatly appreciated.

tks/Roger
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  #2  
Unread 03-03-06, 05:12 AM
Dave Underwood Dave Underwood is offline
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The gear on my 1977 FT337GP had similar problems with inconsistent door closing. The main indicator was the amber light staying on and then the need to cycle the gear again.

BTW when you turn the master switch off, you reset all the solenoid positions and all the valves in the pack which is what is suggested in the emergency proceedures.

In our case we rebuilt the door open & close solenoid along with replacing most of the seals in the power pack. The actual problem was a gear up mirco switch on one of the main that was flakey and seemed to react to air loads. We replaced that switch and did a total re-rig on the gear.

So far so good as I search for wood to knock on.

My advice would be to carefully check all the gear rigging and switch rigging per the service manual and check all the switches in the system.

Regards - Dave
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  #3  
Unread 03-03-06, 07:46 AM
Keven
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A few years back I had a similar problem on my 337A with the doors not closing and it ended up being the solenoid in the power pack.

FWIW

Keven
________
bondage girl Cam

Last edited by Keven : 04-23-11 at 05:18 PM.
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  #4  
Unread 03-03-06, 02:27 PM
Pete Somers Pete Somers is offline
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This sounds like the nose gear uplock is not rigged correctly or the uplock switch is faulty or misrigged.

Make sure that the rigging of the uplock and downlock switches are done as per the Cessna 337H service manual.
Also time the gear retraction with full voltage on the a/c and check that against the service manual as slow retraction would mean a bad power pack.
Remember in the air the nose gear retracts into the air flow. On the ground you cannot duplicate this.

Clue, if the motor does not shut off,

1 main gear retraction is not complete, ie uplock switches not made.

2. The power pack is not switching from gear up to doors close, which comes back to the above.

Easy to check the uplock switches--

Remove the center console.
Find the in-line connector at the top of the power pack.
Put a multimeter on pin 4 and with the gear up you should have 28 volts here.
No 28 volts here and the doors will not close, and you have a uplock switch faulty or misrigged.

If all this checks out ok, looks like you have as Dave says a power pack problem.

Cheers
Pete
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  #5  
Unread 03-04-06, 07:25 AM
bawb bawb is offline
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Two questions:

When the doors fail to close, is the gear up light on?

When the doors fail to close, does the pump keep running?

Bawb
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