M20J Mooney 201 Series 100 Speed Breaks

[Rick H.]

I need to rebuild my right side speed brake. I have contacted Precise Flight. Does anyone have any other companies that rebuild or supply parts for the 100 Series speed brake?

Thank You

Rick 

[neilpilot]

Did speed cause the speed brake to break?   

[gacoon]

 

depends on the part you need - pretty much Precise Flight is the sole source since they are the manufacturer.

[LANCECASPER]

People make the mistake of spraying Tri-Flo which removes the Aeroshell 22 and there's no lube. Then once they fail they send them in for an overhaul.

Mine were a little noisy and one was a little slower than the other. I took the cartridge out, lubricated the worm and worm gear properly in each, and they both are much quieter and operate the same now. They should be lubed every year at annual. For airframes with TKS it might not be a bad idea to lube or at least inspect them twice a year.

[Rick H.]

I don't know if speed was a factor. I have a 1/4 wear area on the round gear. I'm based out of Granby Co and use them for descending into our mt. airports.

[CAV Ice]

Recently had issues with our RH speed brake (Columbia 400).  Called Precise Flight and they recommended sending both in along with the controller.  Got the controller upgraded and both brakes overhauled for $2069.50.

[PT20J]

The biggest problem with the speed brakes is that nothing is sealed. The grease gets washed out and really needs to be reapplied periodically. According to Precise Flight, water can get into the motors -- this happened to mine -- and render them inop. 

I figured out how to apply grease from underneath by removing the underwing access panel and using a long stick. It only takes a dab. I think this is better than removing the entire cartridge. The top mounting screws are tapped into the aluminum frame which isn't that thick so there are only a couple of threads. When I replaced the cartridges after repair I noticed that a couple of the #8 holes had been previously tapped out to #10s and two more screws would not tighten when I replaced them so now I have four that are oversize. 

Skip

[LANCECASPER]

6 hours ago, CAV Ice said:

Recently had issues with our RH speed brake (Columbia 400).  Called Precise Flight and they recommended sending both in along with the controller.  Got the controller upgraded and both brakes overhauled for $2069.50.

Less than 20 years ago they were rebuilding the cartridges for Mooneys for less than $200 a side, or they would do an inspect and replace as necessary. There is very little to these mechanisms. There's a thread on here where a mechanic rebuilt one for very little $$.

 

[PT20J]

The other thing that screws them up is spraying silicone or Tri-flow into them. It gets into the clutches (unsealed of course) and causes them to slip.

[sleeper-319]

10 hours ago, PT20J said:

I figured out how to apply grease from underneath by removing the underwing access panel and using a long stick. It only takes a dab.

Is it pretty obvious once you get the inspection panel off? 

[PT20J]

15 hours ago, sleeper-319 said:

Is it pretty obvious once you get the inspection panel off? 

The whole frame is open. The gear set is a wheel and worm at the top which you can reach with a long thin stick.

EDIT: I was in the hangar this morning and looked at the speed brakes again and it looks to me like it would actually be easier to lubricate them from the top without removing any panels. The worm gear is easily reached with something like a coffee stir stick.

Edited November 23, 2021 by PT20J