Speedbrake does not fully retract

[Jetpilot86]

On 3/2/2024 at 2:07 PM, LANCECASPER said:

Do whatever you have to do to get the cartridge all the way out if it's been years since they've been serviced. Hit each of the top screws with some Kroils to penetrate and loosen it up. Then after awhile, get a high quality, correct size, philips screwdriver and try the top screws by hand. The ones that don't come out you can carefully use an  EZ-out. (Those really don't look like the right screws . .  but maybe)

Once you get the cartridge out, then clean every bit of the old junk off of the worm and worm drive. You might need to use a swab and some alcohol to carefully clean just the worm and worm drive.  Then I would re-grease with Aeroshell 22 and plug them back in and exercise them a lot to see if you can get them to do what they should do. If all of that fails then, as a last resort, send that one in for rebuild. (Others have gone deeper into theirs' and revived them. I've never had to.)

DMax informed me this week that if one goes in, both have to along with whatever part of the system is in the Avionics bay. 4 AMU’s to OH all of it. 

[Lax291]

Yikes, $4K to overhaul something I've learned to live without so far! Have many more things to spend that money on before the brakes. 

Was able to get the screw extractor working and took out the first 12 without issue.  If I can't get them working, they're staying Inop until I can light 4AMUs on fire...

 

[PT20J]

42 minutes ago, Lax291 said:

Yikes, $4K to overhaul something I've learned to live without so far! Have many more things to spend that money on before the brakes. 

Was able to get the screw extractor working and took out the first 12 without issue.  If I can't get them working, they're staying Inop until I can light 4AMUs on fire...

 

And, don’t expect them to repaint your chipped blades. That’s not included. I had to do my own after overhaul. 

[Jetpilot86]

49 minutes ago, Lax291 said:

Yikes, $4K to overhaul something I've learned to live without so far! Have many more things to spend that money on before the brakes. 

Was able to get the screw extractor working and took out the first 12 without issue.  If I can't get them working, they're staying Inop until I can light 4AMUs on fire...

 

As mine failed on my first flight picking the plane up from prebuy, after I paid for it of course, I'm used to not having them.  So far I haven't needed them, but I've also stayed away from busy airspace.

[ArtVandelay]

DMax informed me this week that if one goes in, both have to along with whatever part of the system is in the Avionics bay. 4 AMU’s to OH all of it. 

Are you sure, I just had mine done and it was 2 AMUs.

[Jetpilot86]

5 hours ago, ArtVandelay said:

Are you sure, I just had mine done and it was 2 AMUs.

I like your answer better, who did you talk to?

[ArtVandelay]

I like your answer better, who did you talk to?

That’s actually what I was charged, no hearsay, $2000+shipping.

They replaced 2 gears and a motor clutch or clamp on each speed brake.

In my case one wasn’t deploying properly, but they insisted on overhauling both.

[dkkim73]

3 hours ago, ArtVandelay said:

That’s actually what I was charged, no hearsay, $2000+shipping.
 

I was also quoted $4000, by precise flight via the Mooney factory service center. 

Apparently they had not had the 1000-hour service with the previous owner and so no repair was offered, only full overall.

Maybe that explains the difference?

BTW I have the newer electric ones where the box coordinates deployment, sounds like same as the OP's, left intermittently sticks out about 1/2". 

 

[Rmnpilot]

I received this earlier this week from Precise Flight for the older 100 series  electric speed brakes 

[Marc_B]

Within the past year, Precise Flight also decided to "no longer sell any internal components for the speed brakes for liability concern."  I reached out for a set of retraction springs and it's now a no go.  So if you need service on the speed brakes, you'll more than likely need to send them in for comprehensive service.  My guess is that it is easier for Precise Flight to just replace most of the components and circuits rather than try to troubleshoot issues.  So instead of service they just offer complete rebuild and price accordingly.

But you'd think for that price they should absolutely touch up the paint on the blades...

[N201MKTurbo]

For $4000, if I cannot make them work, I’ll remove them.

[Jetpilot86]

1 hour ago, dkkim73 said:

I was also quoted $4000, by precise flight via the Mooney factory service center. 

Apparently they had not had the 1000-hour service with the previous owner and so no repair was offered, only full overall.

Maybe that explains the difference?

BTW I have the newer electric ones where the box coordinates deployment, sounds like same as the OP's, left intermittently sticks out about 1/2". 

 

My guess is that people, me, are assuming that when they say $2k, it’s $2k per after you realize you have to send both. When in reality it looks like it’s $2k for the set, flat rate. 

[PT20J]

If they do both for $2K it’s reasonable since they charged me almost that much to do one a couple of years ago. They told me at the time that they replace the switches, clutch and motor because they are not hermetically sealed and fail due to moisture. They also replaced the springs which had some light corrosion. They did not paint them or repair stripped screw holes on the frame even though I asked. 

[dkkim73]

2 hours ago, Jetpilot86 said:

My guess is that people, me, are assuming that when they say $2k, it’s $2k per after you realize you have to send both. When in reality it looks like it’s $2k for the set, flat rate. 

Possibly, though might also a different model (they require both brakes and the brain box to be sent). It could also be more because of the lack of the interval service. The quotes came via the A&P so I did not get the nuances. Planning to do them at the beginning of next annual at this point (several knowledgeable folks suggested it was more reasonable to defer, as this all came up right before I was going to get the plane). 

[Lax291]

Alright, got both brakes out & cleaning them up now. First thing I noticed was the left brake (good one and first picture) has the last thread of the worm gear somewhat lined up with the bottom of the red frame. The right brake (bad one and second picture) has many more threads showing. Additionally, when I tip the right cartridge upside down the brakes freely deploy where the left brake does not deploy when inverted. 

 

More to come...

[Lax291]

Think I've found the issue, the spring.  First picture are my brakes and you can see there are different screws lengths where the spring anchors. Second picture is one I found on Google with the screws about the same length. 

Can anyone else confirm their series 100 brakes have the same length screws where the spring attaches to?

[PT20J]

That's not per the drawing. I suspect that the spring broke and someone jury rigged this to make a shorter spring fit.

_ 000S001D_Rev B_Drawing Package_08_14_2014.pdf

[Marc_B]

Looking at the drawings it shows the retraction spring and a part number.  Century Spring Corp SPC-9529 is their part number and they can produce these...BUT, they are custom parts and would need a minimum of $800-900 order.   Not sure if anywhere else would have these other than Precise Flight; and PF will replace them with service, not not sell them anymore.

[Marc_B]

Looking at the pictures of the units...can these be lubricated while installed?  It seems that the worm gear may be more accessible from the top?  Although I keep thinking that I've read that it's accessible from the bottom access panel and a long brush/stick applicator?  Does anyone have any tips or tricks?  Certainly if removed they look super easy to clean and lube.

[PT20J]

3 minutes ago, Marc_B said:

Looking at the pictures of the units...can these be lubricated while installed?  It seems that the worm gear may be more accessible from the top?  Although I keep thinking that I've read that it's accessible from the bottom access panel and a long brush/stick applicator?  Does anyone have any tips or tricks?  Certainly if removed they look super easy to clean and lube.

I used to do it from underneath with an acid brush attached to a dowel for length. But I discovered it's easier to lube them from the top by lifting the blades to get access. All you need is a little dab of grease on the worm gear. Too much grease just makes a mess and attracts dirt.

[ArtVandelay]

If I was Lax I would just send them in to be overhauled at this point, who knows what else was done by a PO.

[Lax291]

Very happy to report the brakes a retracting fully now. Turned out all that was needed were adjustment to the cams that trigger the up and down limit switches. I adjusted both cams on both sides and all is working well now. Thanks to everyone for the help and assistance!  Below is a view of the cams, very easy to adjust. 

[Tyler G]

On 1/14/2021 at 10:41 AM, MatthiasArnold said:

Hallo Fritz,

I experienced some problems with my electrically actuated Precise Flight speed brakes as well after I purchased my O2 last summer. PF is not to blame at all - obviously they never got serviced since the plane left the factory in Kerrville in 2006. 

You can find the service manual at the PF website. I inspected and serviced them in accordance with the manual. Clean, remove the old grease, apply fresh grease (Aeroshell 22 if I recall correctly), apply tons of „Kontaktspray“ to the microswitches (with speed brake flaps in different positions), test them. During the re install take care of the electrical connectors as well (clean and apply „Kontaktspray“). As stated in the service manual apply the suitable Loctite to the screws. Test after installing, make logbook entry.

Since servicing they work like a charm!

If you have trouble dismounting the speed brakes, gently push from the bottom of the wing..

Regards,

Matthias

Solid response. Clear instructions and photos. I wish everyone on this forum could respond like this. Great job!

[TheBearFlies]

So after reading this entire thread…mine need, clean and lube, rebuild, or cam adjustment. I think clean and lube is a good start.

Previous flight, SB worked perfectly.

Day of issue I flew from KGPM (Grand Prairie, just south of DFW) to 99V (Crawford Airpark CO). Plane was at KGPM for 3 days. First night it rained cats and dogs and when I went to depart there was a layer of dirt on my plane. Started at 8k, +2 hours 10k, +3 12k, +3.5 16k for crossing the Rockies. While level at 16k +15min I look out to the right and see this. Right SB deployed about 1/4 inch. I attempted deploying SB, no joy on both.

They did not work in the descent but then deployed after landing. The right would not stow completely but upon shutdown, stowed completely. 

[Lax291]

My issue was the brakes not resting flush in the down position. Turned out it was adjusting the cams that did it, but probably didn't hurt that I cleaned and lubricated as well. The cams were actually very easy to adjust once the cartridges are out. It's small adjustments until the up cam hits the limit switch (the tricky part is having it hit at the correct up or down position) and then the same with the down cam. I'd be happy to review what I did if that helps at all, feel free to PM me.