HE626 flap actuator bleeding

[Kesk]

I know there are many threads out there for bleeding the flaps but I'm wondering what people have used to pump fluid when doing a bottom-up bleed. I assume top-down will not get them good enough. I've only ever bled brakes and either used a hand pump with vinyl tubing or the ATS bleeder that has a connection for the caliper bleeder screws. When people say they are using a pressure pot, what are they actually connecting to on the actuator and how?

 

[47U]

2 hours ago, Kesk said:

When people say they are using a pressure pot, what are they actually connecting to on the actuator and how?

I have an automotive brake bleeding pot I got from the auto parts store.  Some have used a cheap garden sprayer.  It doesn’t need to be very big.  

To bleed the flaps, the connection is made at the T on the flap actuator.  It’s a male -4 AN flared fitting.  Appropriate fittings to connect the hose off the pot to the T can be sourced about anywhere, including Aircraft Spruce and your local auto parts or hardware store.  

I found that it works better to loosen the flap retract rate screw (with the big jam-nut) on the flap pump in order to flow more hydraulic which helps push the air out of the system.  Of course then, you’ll be adjusting and readjusting the rate screw forever, until you get it ‘just right.’

[Kesk]

5 minutes ago, 47U said:

I have an automotive brake bleeding pot I got from the auto parts store.  Some have used a cheap garden sprayer.  It doesn’t need to be very big.  

To bleed the flaps, the connection is made at the T on the flap actuator.  It’s a male -4 AN flared fitting.  Appropriate fittings to connect the hose off the pot to the T can be sourced about anywhere, including Aircraft Spruce and your local auto parts or hardware store.  

I found that it works better to loosen the flap retract rate screw (with the big jam-nut) on the flap pump in order to flow more hydraulic which helps push the air out of the system.  Of course then, you’ll be adjusting and readjusting the rate screw forever, until you get it ‘just right.’

 

Thanks, I think an automotive one would work better here then possibly. If not I believe the ATS hosing can come off for tubing that connects to a flared fitting similar to the drain overflow. If I get exact part numbers I'll post them here once the job is done.

[Shadrach]

 

I use a Motive pressure bleeder. It’s a tight space. I push a piece of vinyl tubing over the fitting. The ID of the vinyl that fits over the fitting is the same size as the OD of the vinyl tube that comes on the pressure pot. They can be connected with hose clamps. Not ideal, but it works.

https://www.amazon.com/Motive-Products-100-System-Bleeder/dp/B00CJ5DV2I/ref=asc_df_B00CJ5DV2I/?tag=hyprod-20&linkCode=df0&hvadid=312634019511&hvpos=&hvnetw=g&hvrand=10477568999880027208&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9008066&hvtargid=pla-568407457373&psc=1&mcid=c4ffda30e4823882ae1c476d60c4cbc0&gclid=CjwKCAiAlcyuBhBnEiwAOGZ2S-BQBFgcM90SYVET7fWbmM4qMVpTOWv6l3u1hp94rU-M2WqS18nulBoCct4QAvD_BwE
 

[Kesk]

Okay, I now understand that there's the pump and then the actuator. We're resealing both. The HE-625 was horrific. Here's the setup.

The fittings are Aeroquip and Speedway, the hose is Aeroquip 306-4 but any 1/4" ID hose should work, got it off Aircraft Spruce. The nipple on the bleeder is 5/16" but I figured 1/4" would work and it does. The overflow line is just a 1/4" NPT thread and some random tubing my workplace had, got the fitting from Ace Hardware.

Edited March 14, 2024 by Kesk