n5756k Posted January 22, 2017 Report Share Posted January 22, 2017 I have vacuum operated speed brake that lag when retracted. I'm interested in changing them to manual cable operated speed brakes. Does anybody know where I can get a set, and can they be installed in a 1984 M20J? Tom Moquin N5756K Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 22, 2017 Report Share Posted January 22, 2017 Contact the builder of the speed brakes... https://www.preciseflight.com/general-aviation/shop/speedbrakes/products/speedbrakes-mooney/ They come in three versions... - manual - pneumatic - electric Converting from one to the other may be unlikely? Overhauling the parts will make them work like new again. Even the newer electric ones get OH'd. PP thoughts... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 22, 2017 Author Report Share Posted January 22, 2017 Who would you recommend to overhaul the speed brakes? I have had two shops look at them but they weren't any help. I called Precise Flight, but they weren't interested in this at all. The speed brakes work pretty good on the ground but slow to retract in the air. They work better in warm weather than cold. I had Weep No More reseal my fuel tanks soon after buying the airplane. I'm thinking the the cables in the wings might have thick fuel residue. I believe the cables are enclosed in a coil type housing, on the idea of a throttle cable on a lawn mower. If this residue was on the housing it could penetrate down into the cable and be a sticky mess. Quote Link to comment Share on other sites More sharing options...
carusoam Posted January 22, 2017 Report Share Posted January 22, 2017 The vacuum drive system is pretty simple, but prone to aging. A small leak in the system may show up as a lazy deployment. See if you can find the plumbing layout in your POH? This would be a project for the annual when all the tubing is made more visible in the wings? Check with your MSC to see if they have enough expertise to run down all the plumbing and fittings? Falling back on a cable system sounds a bit extreme. They would go great with manual gear and hydraulic flaps though... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
MHemperly Posted January 22, 2017 Report Share Posted January 22, 2017 11 hours ago, n5756k said: I have vacuum operated speed brake that lag when retracted. I'm interested in changing them to manual cable operated speed brakes. Does anybody know where I can get a set, and can they be installed in a 1984 M20J? Tom Moquin N5756K I wonder if your current set up can be converted at a lower cost? Is that a fly-in community in that picture? Where is it located? Mike Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 22, 2017 Author Report Share Posted January 22, 2017 Don Maxwell checked for leaks and checked the bellows, that was fine. Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 22, 2017 Author Report Share Posted January 22, 2017 It is a fly-n community. I live at "Casa De Aero" (68IS) in Hampshire, IL. it is about 32 northeast of Chicago O"Hare (ORD). 1 Quote Link to comment Share on other sites More sharing options...
Guitarmaster Posted January 23, 2017 Report Share Posted January 23, 2017 It is a fly-n community. I live at "Casa De Aero" (68IS) in Hampshire, IL. it is about 32 northeast of Chicago O"Hare (ORD). I fly right over you on the way to work! I'm at C77.Sent from my XT1585 using Tapatalk Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 23, 2017 Author Report Share Posted January 23, 2017 Poplar Grove, I know it well. 1 Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted January 23, 2017 Report Share Posted January 23, 2017 It appear to me that Precise is only offering the electric version now. Sounds to me like the cable needs cleaning/lubing, perhaps replacing but I don't know what's involved in that. I bet DMax has run into it though. http://www.donmaxwell.com/ McFarlane might be helpful if you can be more precise on what the cable/sheathing is. They might be able to make a new cable(s). I'm just guessing. http://www.mcfarlane-aviation.com/ FWIW, I have the original manual version installed 20 years ago. I don't think they've ever needed service. Handy to have. Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 23, 2017 Report Share Posted January 23, 2017 (edited) 2 hours ago, n5756k said: Don Maxwell checked for leaks and checked the bellows, that was fine. If the vacuum system is fine and they hang going down I'd bet you'll find the cable sheath's are coming apart. The spring to retract them can be an issue too, but they usally work fine till they break yet they are also available from Precise. The cables sheaths though just don't last 30-35+ years, they get brittle and crack and then the brakes don't go back down easily. You can still get replacements from Precise Flight. But the first step is always to inspect the entire system and see where the issue(s) are. You can examine your cables from the rear of the wheel wells. You can also check your spring by pulling the speed brake up with your fingers and see how well they retract back down. (Don't do this on electric ones). 2 hours ago, n5756k said: I'm thinking the the cables in the wings might have thick fuel residue. I believe the cables are enclosed in a coil type housing, on the idea of a throttle cable on a lawn mower. If this residue was on the housing it could penetrate down into the cable and be a sticky mess. They shouldn't, the cables don't go into fuel bays. With Monroy's they are sealed off. But if the sheaths have lost their integrity that will be your problem and their replacement will get them going again. Edited January 23, 2017 by kortopates Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 23, 2017 Author Report Share Posted January 23, 2017 I don't have any manuals for them. Quote Link to comment Share on other sites More sharing options...
n5756k Posted January 23, 2017 Author Report Share Posted January 23, 2017 I don't have any manuals for them.I wonder what it would cost to change the cable. Quote Link to comment Share on other sites More sharing options...
kortopates Posted January 23, 2017 Report Share Posted January 23, 2017 2 hours ago, n5756k said: I don't have any manuals for them.I wonder what it would cost to change the cable. I don't recall, but not what I would consider expensive. Precise of course will be be able to tell you.They make these up order based on your type and serial # as I recall. Quote Link to comment Share on other sites More sharing options...
Oldguy Posted January 27, 2017 Report Share Posted January 27, 2017 On 1/22/2017 at 4:56 PM, n5756k said: ... I'm thinking the the cables in the wings might have thick fuel residue. I believe the cables are enclosed in a coil type housing, on the idea of a throttle cable on a lawn mower. If this residue was on the housing it could penetrate down into the cable and be a sticky mess. I have the vacuum controlled units and had the same problem with my left speed brake. Cleaned both the pivot points in the brake unit and the cable. Works well since with no delay in retraction. One last thing to check is the drain from the unit for water that gets in it. If it gets plugged, it will build up "scum" over time and slow down or stop retraction. Quote Link to comment Share on other sites More sharing options...
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