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-   -   Gear leg has excessive toe out (http://www.vansairforce.com/community/showthread.php?t=148485)

V111Pilot 04-10-2017 09:40 AM

Gear leg has excessive toe out
 
After going through tires in one season, three seasons in a row (about 100 Hrs/yr), I finally checked the toe of the gear and found that the right side had excessive toe out (by using a piece of aluminum angle against the brake disc, extending forward about 18" the end of the angle was about an inch to the outside).

Assuming this was a bent gear leg I sent it to LangAir and it is within specs.

SO, one solution I am told is to use an oversize bolt and re-drill the bolt hole in the gear/engine mount. Would this would require removing the mount?

The other option given by LangAir was to use a "Step bolt", does anyone know how this is done or have a diagram/pic?

Any other method/advise is much appreciated.

Thanks

JonJay 04-10-2017 10:52 AM

Sorry I am not much help. However, you might be time and money ahead just to buy a new leg and drill it correctly. You would know it was done without compromise.
One option might be to ream for a taper pin. You would want to make sure this was ok with Vans but there is a lot of "meat" at that end of the leg. It would take a good machinist to set this up properly and you would have one shot at getting it right. Tapering an existing hole for a new path in tempered steel wouldn't be easy. I have only done it in a true hole. A taper reamer that size will set you back some $$ too.
I don't know enough about the engineering of that joint to help you on the "stepbolt" idea. I imagine it would involve enlarging the holes in the socket on the engine mount and finding or machining a bolt to the correct tolerance to rotate that leg just right. Sounds like a challenge.

Hopefully someone who has had this issue will respond with some better ideas.

roadrunner20 04-10-2017 12:46 PM

Quote:

Originally Posted by V111Pilot (Post 1164360)

SO, one solution I am told is to use an oversize bolt and re-drill the bolt hole in the gear/engine mount. Would this would require removing the mount?

I am one of the guys who oversized the bolt with success. I did not remove the mount. It helps with aligning by having the gear on.
Here's the thread with some pro & con comments.
I probably agree with them now regarding lifting by using the engine ring was probably not the best approach.

http://www.vansairforce.com/communit...ght=toe&page=2

JonJay 04-10-2017 12:51 PM

Yay Dan! I forgot you had to do this. Much better approach than the other ideas.

Mel 04-10-2017 12:53 PM

First, make sure you are measuring correctly. Was the gear off the ground while measuring? With the gear suspended, you are shooting for "0" toe-in/toe-out.
When correctly aligned, the RV style landing gear will have a slight amount of toe-out with the weight of the aircraft on the gear.

tturner 04-10-2017 09:31 PM

I had this same problem on my RV-4 and fixed it last fall. I also sent the gear legs to Langair and they said they were ok. It was my right gear that had excessive toe out of about 2 degrees. If I remember correctly the bolt thru the gear leg is 5/16. I drilled the hole in the mount out to 3/8. I then had a friend make me some offset bushings with a 5/6 I'd and 3/8 od. This gave me about .025 of offset adjustment which was a little more than I needed so I would estimate the I only used about .020 to fix my problem. The buishings had a step on the outside which butted up to the outside of the engine mound and was squared off so I could put a specially built narrow wrench on them to adjust the offset. Unforuntly I don't have any pictures. The drilling and installing the bushings took less than an hour. I have flown it about 40 hours since and it is fine. Call me if you would like to discuss it. 770-639-6900.

AX-O 04-10-2017 09:33 PM

Quote:

Originally Posted by JonJay (Post 1164380)
you might be time and money ahead just to buy a new leg and drill it correctly.


You don't have to drill the new gear legs/engine mount on -4s. That is completed when built by the work shop.


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