Re: PT leaky fuel valve

Ranchaero Wing Shop · Post by **Ranchaero Wing Shop** » Tue May 07, 2019 1:23 pm

'My PT-19 fuel valve is leaking out the top actuator shaft hole. I took
it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

...or, anyone have a spare I could buy?

David'

Paul Cousineau · Post by **Paul Cousineau** » Wed May 08, 2019 7:06 am

'There is some NOS fuel valves on eBay

Sent from my iPhone

On May 7, 2019, at 12:20, Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

My PT-19 fuel valve is leaking out the top actuator shaft hole. I took
it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

....or, anyone have a spare I could buy?

David

'

Curt Kinchen · Post by **Curt Kinchen** » Wed May 08, 2019 7:49 am

'You are right. The cork is the seal. On the larger T-6 valves they made a plastic replacement "cork". I don't think that's ever been done for the small valves.
I've had some success with liberal application of fuel lube. The old style really thick waxy type is probably better than the later, currently sold thinner version.

On Tue, May 7, 2019, 12:23 PM Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

My PT-19 fuel valve is leaking out the top actuator shaft hole. I took
it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

....or, anyone have a spare I could buy?

David

'

Joe Preston · Post by **Joe Preston** » Wed May 08, 2019 8:26 am

'

If you are looking to replace the valve, you should be able to use AC23-27 to find a suitable OEM replacement. I used that to install a ball valve from a Cub
when I rebuilt my Champ. I got rid of the leaky cone valves for a much better ball valve.

If you are unfamiliar with this AC, I encourage you to read it. It discusses replacing parts on Vintage aircraft with newer ones from other manufacturers.

Joe

From: fairchildclub@yahoogroups.com

Sent: Wednesday, May 08, 2019 9:49 AM
To: fairchildclub@yahoogroups.com
Subject: Re: [fairchildclub] PT leaky fuel valve

You are right. The cork is the seal. On the larger T-6 valves they made a plastic replacement "cork". I don't think that's ever been done for the small valves.

I've had some success with liberal application of fuel lube. The old style really thick waxy type is probably better than the later, currently sold thinner version.

On Tue, May 7, 2019, 12:23 PM Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

My PT-19 fuel valve is leaking out the top actuator shaft hole. I took

it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

.....or, anyone have a spare I could buy?

David

'

Thomas Rood · Post by **Thomas Rood** » Wed May 08, 2019 9:37 am

'Try smearing all of the pieces with a THIN layer of fuel proof grease.

Sent from Yahoo Mail on Android'

Ranchaero Wing Shop · Wed May 08, 2019 10:02 am

' Thanks, Paul. There was 1 NOS fuel valve left on Ebay so I bought it.

AC23-27 may be the better long term solution as Joe mentioned. Anyone know of a possible replacement?
Thanks for the excellent help guys!

David

On 5/8/19 6:05 AM, Paul Cousineau couse1@aol.com [fairchildclub] wrote:

There is some NOS fuel valves on eBay

Sent from my iPhone
On May 7, 2019, at 12:20, Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

My PT-19 fuel valve is leaking out the top actuator shaft hole. I took
it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

.....or, anyone have a spare I could buy?

David

'

Ranchaero Wing Shop · Wed May 08, 2019 10:33 am

' Fuel proof grease? where could I find such a grease? Searching Internet I see EZ-Turn Lubricant/Sealant at ACS. Says it works on fuel valves.

Before I ordered the NOS fuel valve from Ebay, I had another couple of (untested) ideas:

1) There may be room for a tiny cross-section "O"-ring on the shaft at the end of the cork cone where it exits the housing. I ordered one from The O-ring Store online. Waiting for it to arrive.

2) Maybe a washer or two stacked under the spring to increase pressure on the cone might help a little. Maybe the springs relax some over time.

The new NOS on the way from Ebay should solve my problem for now at least. The Fuel-proof grease might be a good idea anyway.

David

On 5/8/19 8:35 AM, Thomas Rood tdrood@yahoo.com [fairchildclub] wrote:

Try smearing all of the pieces with a THIN layer of fuel proof grease.

Sent from Yahoo Mail on Android

'

Thomas Rood · Post by **Thomas Rood** » Wed May 08, 2019 10:50 am

'That's the stuff - a tube will last you a millenium, but once you use it, you'll never understand how you ever got by without it. I had a gascolator that would not stop leaking no matter what I did - new plunger, new orings, nothing. Then someone suggested this stuff - has not leaked since - 7 years and counting! Obviously, it has its limitations, but couldn't hurt to try it. If it doesn't work, then just do as already suggested and change to a modern valve using the AC as justification.

Sent from Yahoo Mail on Android'

Francis Cox · Post by **Francis Cox** » Wed May 08, 2019 12:07 pm

'Have you thought of these? - I swapped out the original heavy leaky valves on my Argus (UC61K) for a couple of these and had them modified to fit the original operating levers so no one would know that these valves were there.
http://www.andair.co.uk/category/fuel-selectros-three-eighth-inch/
Spruce have them -
https://www.aircraftspruce.com/search/search.php?s=andair%20fuel%20valve
Frank Cox

On Wed, 8 May 2019 at 17:02, Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

Thanks, Paul. There was 1 NOS fuel valve left on Ebay so I bought it.

AC23-27 may be the better long term solution as Joe mentioned. Anyone know of a possible replacement?
Thanks for the excellent help guys!

David

On 5/8/19 6:05 AM, Paul Cousineau couse1@aol.com [fairchildclub] wrote:

There is some NOS fuel valves on eBay

Sent from my iPhone
On May 7, 2019, at 12:20, Ranchaero Wing Shop david@ranchaerowingshop.com [fairchildclub] wrote:

My PT-19 fuel valve is leaking out the top actuator shaft hole. I took
it apart and it's basically a cork cone inside an aluminum cone with a
couple springs to put pressure on the two, and a channel to align with
the selected inlet/outlet. I don't see anything else to seal it. The
cork looks "pretty good" but there are some slight irregularities which
must be causing the leak. I'm at a total loss how to rebuild the cork.
Anyone have experience with these?

.....or, anyone have a spare I could buy?

David

'