Tip: Cheap static leak test

[Lan Vinh Do]

Hi
I am in the process to put my new rv-10 IFR with transport Canada.
I need to do my 24 month but last time that I did a 24 month on my old rv-7, I paid a avionic shop many hours because there was a big leak. They has to find it before they could begin the 24 month. (really expensive when you pay somebody to do what you can do yourself)
I decided that this would not happend again. I was supposed to have a friend (aircraft mecanic ) that could bring the static pump to test the plane for a leak before i go to the avionic shop. Unfortunately, he just moved far away a couldn't help me before.
So i test my airplane with a cheap setup. See the pictures. I have put a T pneumatic connector behind my instrument on the static line, block the static port on both side and hook a medical seringe 30 cc. When you use a 1/4 vinyl line, it will fit perfectly on the seringe air tight. ( the nylon plastic tubing will not fit, you need the vinyl tubing) . The other end fit in the T connector)
With the seringe, you can do a gentle succion. You can clamp the tube or better, put a speed controller on the line and close it when you have the succion that you need.
I found a big leak that way. So I used another setting. I've put a Y pneumatic connector. One side with a old altimeter that i removed from my panel when i did a upgrade, the other side with the seringe and the speed controller fitting, and the third on each line that i want to check. I began by the tail and i found rapidly the leak on one of the connector near the static port. I removed the old normal plastic fitting and mount the static line with the pneumatic fitting. Really faster, less pain ( the time pass in the tail) and really no leak at all. With this setting, you can test all segment that you want and not always the whole system.
I retest it on the T connector behind the panel and I only have a 5ft /min leak at 1000ft above ground level ( well below the 100ft/min allow by transport canada)
I know, it's not perfect because you cant be sure that the last plug that you put on the T fitting is not leaking but if it leak when i will go to the avionic shop, I will know where the leak is.

Be carefull when you test it that way. Don't go over 1000ft above ground level. I think you can damage your ASI or other sensors from the EFIS because the pitot is not on the pump system as in a avionic shop.

I have put the link to the picasa album.
https://picasaweb.google.com/lanvinh...eat=directlink

[Mike S]

This is a good idea, I like the use of the altimeter for a leak detector.

Thanks for sharing this.

[Bavafa]

I have been using a rather cheap vacuum/brake bleeder pump kit from Harbor freight. But I would caution not to go to 1000 very quickly as it can damage your instrument. I usually pull enough vacuum for 100-200 feet and wait to see how much drops as I time it.

[hevansrv7a]

I have an EFIS so perhaps that makes this easier. Not sure. If you disconnect the static at some point, close up the port(s) on the fuse and suck with your mouth on the disconnected line (I used the one for the autopilot) until you get the speed or altitude indication that you want for a starting point, then put your tongue over the end of the tube you will see or not see a leak.

If it leaks much at all I know I have to find it. Don't need a pump or a special instrument, just a wristwatch.

[Lan Vinh Do]

You are not worry about std (sport plane transmitted disease??)

[hevansrv7a]

Originally Posted by Lan Vinh Do

You are not worry about std (sport plane transmitted disease??)

My airplane and I are in a monogamous, exclusive relationship.

[aerhed]

You sure she's not doin' touch n go's when you're not around?

[hevansrv7a]

Originally Posted by aerhed

You sure she's not doin' touch n go's when you're not around?

It was a c*****y belt.
Lock on the airport.
Tower 24 x 7.
Lock on the hangar.
Tachometer hours meter.
But no, you can never be sure..

[Jim P]

Question on this thread....once you know you have a leak, what's the best way to actually find it?

[Lan Vinh Do]

Hi jim
What i like with my setting with the altimeter ( see the album in the first post) is that you can hunt for the leak. Open your system , test one side, test the other side. If one side leak, go search on this side. When i test mine, i test near my alternate static ( all my instrument, ahrs, altimeter, asi, autopilot are after my alternate static and the rest uf the tubing are between the alternate static and the static port. ) . I test the side that go toward all my instruments and find no leak so i knew that all these connection between my instrument were OK. The other side toward the tail show a big leak. So i start from the tail at the right port side, no leak. Test every connection and found the leak in the t fitting that connect my right and left static port. I retest it near the alternate static and didn't find a leak anymore so my hunt was finish. If it was still leaking, i would continue fitting by fitting or you can skip some fitting and go farther to test it and if you find no leak, you saved some time. ( with the pneumatic fitting, it go really fast. )

Lan Vinh Do