Replacing the landing gear legs

[Paul Misteli]

Hello

I have a question, I need to replace my Cessna 170B landing gear legs, how can I jack up the plane so that i can remove the legs?

Maybe anyone have Pictures?

Thank you for help and Kind regards

Paul Misteli
Cessna 170B, 1952
HB-CYV

[n2582d]

Hello Paul,
This thread discusses lifting the aircraft. Did you find any major problems when performing the SID inspection?

[Bruce Fenstermacher]

From Jim Wildharber:

[Paul Misteli]

Hello Jim and N2582D

Thank you for your informations, at the Moment i am no Problems with the SID inspections.

[jlwild]

Paul, you are welcome. In the three pictures Bruce posted above for me, the stand shown was only used for holding (suspend) the plane once the landing gear was removed.

To lift the plane, I used a jack and spring jack pad normally used for removing the wheels. So, I jacked one wheel up until off ground, then attached strap shown in picture to the engine mount. Next I shifted the jack and Spring jack pad to the opposite side and jacked it up level with the first side. Then I attach the second strap to the engine mount. With the plane now suspended by the two straps, I removed jack and jack spring pad for easy access too both gear legs. I found this method fast and easy. However you need a friend to loan you the frame shown, or make one for yourself.

Note of caution: I have a low ceiling hangar; so, be careful as you jack the first side up, or down, to not hit the ceiling with a wing tip. also remove both landing gear fillets prior to jacking. Re-install fillets after landing gear is installed and wheels are back on hangar floor.

[blueldr]

I have used a 4 x 4 beam, cut to the shape of the fuselage and padded with carpet, on the first bulkhead behind the LG legs and set on cribbing. Just jack the airplane up on the front axles and lower it down on the padded beam. Very stable.

[Ryan Smith]

Jim,

I know you would never do anything to your airplane that would damage it, but are there no considerations to be had for weakening the motor mount? Assuming my math is correct and the shift of weight goes from the main gear directly to the motor mount without any appreciable increase in weight on the tail, you're nearly tripling the weight of what the mount routinely holds. I realize that for certification purposes, the engine mount has to exceed the prescribed load factor for the category, but those loads are only momentary, albeit with a greater shear onset than slowly lowering the airplane and allowing the mount to ease into the new load.

Just trying to learn. The topic of hoisting seems to be a difficult rabbit to skin.

[cessna170bdriver]

... you're nearly tripling the weight of what the mount routinely holds. ...

Are you including the utility load factor AND the propeller gyroscopic loads that those joints are designed to take?

I don't think there's any structural problem with what Jim did. If he'd lifted the whole airplane by the engine lift lug, THAT would be a different story.

[Ryan Smith]

... you're nearly tripling the weight of what the mount routinely holds. ...

Are you including the utility load factor AND the propeller gyroscopic loads that those joints are designed to take?

I don't think there's any structural problem with what Jim did. If he'd lifted the whole airplane by the engine lift lug, THAT would be a different story.

It's late, and I've burned the candle at both ends the past couple days and nights on a project. Admittedly, my logic is probably not the best right now.

I had a beautifully articulated post regarding Utility category load limits until I realized that I was using the wrong load direction. I guess I can make a joke about how strong the '55 engine mounts are since yours stopped a Cherokee dead in its tracks.

I'm not here to argue (all the time), I'm just trying to glean as much from some of the well-seasoned and experienced 170 drivers on here.

[voorheesh]

The Cessna Single Engine Service Manual, Section 2 Ground Handling, Etc. has a procedure for hoisting the aircraft using the upper engine mounts or fixtures attached to the upper wing/fuselage. I don't have every service letter/bulletin so this procedure may have been superseded. It was valid in 1960. This would validate using the upper engine mounts to lift the plane. There is a description in the manual of the 4X4 block that BL mentioned.

[jlwild]

Ryan, Voorheesh has it right on the Cessna Single Engine service Manual. And, I used Southland Aviation, a certified repair station, to do the heavy lifting and paperwork. My job was helper to the young mechanic shown in the picture and prep the plane, ie, drain the fuel tanks, remove seats and carpet, etc. When I lived in Alaska in the early 70's this same technique was used on my first 170.

[Blue4]

Not to be glib, but the easiest way is to hoist the airplane by seaplane eyebolts. This can even be done with an engine hoist (for one side).

The eyebolts can be purchased relatively cheaply from Air Repair. The L-19 parts are the same as for the 170. There's a good thread on installation which isn't terribly difficult. No STC required; a logbook entry will keep you legal since the TCDS covers these parts (as part of the float kit).

I generally remove and replace my gear legs about twice a year when I switch to and from floats.

Blue skies and tailwinds,
-Scott