I need to remove my elevator and horizontal stabilizer from MX7 for repair. Can anyone give me some insight on removal. Control cables, struts, ext? I have the manual but it's pretty vague. Any insight is apriciated.

Quick instructions.
Remove rear fairings.
Capture the top and bottom elevator cables with a piece of wire and fasten to frame somewhere.
Remove gapseals.
Disconnect elevators at elevator horns. Photograph so you get all parts back correctly.
Remove right side hinhe pins.
Remove right elevator.
Remove right stabilizer and stabilizer strut.
Release the clamp that holds the elevator trim tab cable sheath.
Remove left elevator after removing hinge pins.
Rest left elevator on a stool as you have not yet disconnected trim cables.
Remove left stabilizer and strut.
Left elevator can be recovered in place, OR you can get more working space by releasing the trim cable turnbuckles, OR you can cut the cables and replace later with new ones.

Hi, thanks Jeremy for those tips on the removal. I ran into a problem with the stabs being stuck to the tube inserts and they won’t budge. Anyone have any tips/tricks for pulling them out?

Thanks in advance!

I’ve read in previous posts the stab removal can be challenging. Lots of penetrating oil, mouse milk is highly recommended. Some have resorted to a slide hammer, though fabric removal would be necessary for that I believe.

On reassembly, maybe do the next person a favor and lightly apply anti-seize compound to the tubes.

Good luck!

Kirk

In addition to lots of penetrating oil, try this:

Remove bolts in strut.
Remove bolt in front stabilizer tube.
Leave bolt in rear stabilizer tube.
With your hand, whack as hard as you can stand on outboard end of front tube, in the rearward direction.
Keep doing this until you get some movement of the front tube off the stub.
Now whack in the opposite direction to line the bolt hole up again in the front tube.
Reinstall front bolt.
Remove rear bolt.
Whack on rear tube, in forward direction until you get some movement of rear tube on stub.
Repeat this process as many times as necessary until you can wiggle the whole thing off the stubs.

The idea is that you are using one bolt as a fulcrum to lever the other tube off a little bit, then switching to do the other one. You can’t go far on one before it binds. After getting it to move a little, you can usually skip re-installing the bolt, and just work back and forth between the two, whacking each way alternately, and kind of holding the other tube from sliding back in. Having a friend to help, well....helps.

If hitting with your hand doesn’t do it, you can try using a soft hammer, but some damage to fabric is likely. You can try padding with a folded rag and using a mallet.

Another method is to slide a strong piece of webbing (spectra is my favorite, but you have to get that at a rock climbing store) between the fuselage and the stabilizer. You are going to make a loop of it, and connect it to a slide hammer, so make it long enough so that you can get it out past the stabilizer. When slide hammering this way, have someone hold the webbing in position close to the tube; if it slides away from the tube, towards the center, it will bend the relatively light channel that forms the inboard edge of the stabilizer. Even holding the webbing close, there is a chance of damage with this method. Lots of penetrating oil and patience are your friends here. A little carefully-applied heat with a heat gun can help: enough to improve wicking of the penetrating oil, but not so much as to damage or shrink the fabric.

Good stuff Andy,

Do you think using anti seize compound will help for the next disassembly?

Also have had a hard time splitting wheel halves. Wondered why they were never coated to help with that...

Sorry for the thread hijack

Kirk

i have auxilliary (seaplane) struts on my horizontal. i was able to attach a slide hammer where these struts bolt on, and bang my stabs off. they were very stuck

Kirk wrote: ↑

Mon Mar 22, 2021 7:17 am

Good stuff Andy,

Do you think using anti seize compound will help for the next disassembly?

Also have had a hard time splitting wheel halves. Wondered why they were never coated to help with that...

Sorry for the thread hijack

Kirk

I do think that anti-seize should help with future removals. Or ACF-50 or Corrosion X. The anti-seize might hang in there longer; not sure. The other two will wick into the metal better, which might be more helpful over the long term.

UP-M5 wrote: ↑

Mon Mar 22, 2021 10:21 am

i have auxilliary (seaplane) struts on my horizontal. i was able to attach a slide hammer where these struts bolt on, and bang my stabs off. they were very stuck

I’d love to see someone attach an air fitting there and pressurize the tube to try to pop it off!

Or maybe fill it with a flammable gas and light it...

Don’t try this at home, folks.

I recently had my Elevator & Horizontal Stab recovered and the right side was incredibly difficult to remove.

Thanks for the responses! Will try Andy’s method and report back.

You'll want to try Andy's response on a friends plane first to get the correct mix of fuel and air!

An old mechanic stunt involves filling a garbage bag with acetylene and touching a cigarette to it to light it off. It makes a very satisfying “WHUMP!!” and a big, short-lived fireball.

I know of two instances where the folks involved misunderstood the process and filled the bag with a mixture of oxygen and acetylene. This resulted in a huge, sharp “BANG!!!”, broken windows, and bleeding eardrums.

Correct mix indeed....

Or a 55 gallon drum with oxy/acet... yes there was alcohol involved.....

Or when your17 and hanging with all you heathen friends and the waterbed fad has died and the store was selling california king size mattresses for 12 dollars and you happen to have two full bottles of O2 and three bottles of acetaline in your Dads farm shop and half a dozen .308 tracer rounds. City kids just don't know what they missed, and those of us who survived are not going to tell them. Now that would remove your horizontal stab. . . .