Landing Gear bolts

After all the fussing and griping about how hard it is to check the torque of the gear bolts on an 8 I am just wondering how many find them to be loose when they actually get some sort of wrench on them, and after the first several condition inspections do they still loosen up yearly.
Just curious.

Neglible

After doing them at 10 hrs then 50, the first annual revealed no changes and only slight ones at 10 and 50 and that could be from changing to a new torque wrench.

Most of the force is actually on the big single bolt/nut anyway as the force on the outside clamps is actually directed upward towards the steel reinforcement plate and the longeron. Of course the force is directed that way in most cases - except if you side load the gear. Still, those little high strength nuts look like PAL nuts to me - I hate them. I sure would feel better with longer bolts and plain old AN365's in there...

Check 'em, you'll feel better next time you have a less than graceful arrival.

Nicely put

Less that graceful arrival..I can relate to that...
Mine haven't loosened since last year and I was just wondering what others find.

My buddy Hog recently discovered loose gear bolts on his RV-8. I don't have any real details other than just that. He's not on this forum, so I could get more detail if you need it. He did mention it was a royal PITA to get to the hardware in those gear towers (I'm looking fwd to that in my own -8).

Thanks Dan

I don't need the details Dan, Thanks though. I was just wondering what was happening out in the field.

ps. how the 8 coming?

RV8iator said:

After all the fussing and griping about how hard it is to check the torque of the gear bolts on an 8 I am just wondering how many find them to be loose when they actually get some sort of wrench on them, and after the first several condition inspections do they still loosen up yearly.
Just curious.

Click to expand...

I just retorqued mine at the 10 hour point. I was able to get 3/4 to 1 turn on each of them.

-Geoff

one of the guys we fly with in an 8 did not check his at the 50 hr mark then jacked the plane up for his inspection using the gear The bolts checked tight (ie leverage from the gear).A few months later he lifted the plane with wing jacks and discovered loose gear bolts and was headed for a big problem. He did have to replace some of the bolts. I do not know wich ones.

I haven't seen any posts from Bryan (Low Pass) recently so I'll mention what I remember about his gear.

Bryan said he checked his gear somewhere between 25 and 50 hours and found them to be extremely loose, to the point that he was very worried about damage to the bolts. He replaced all bolts and nuts.

I had some looseness in the early days (< 100 hrs) but get less than 1/4 turn on any bolts now. Usually can't move any of them.

Warning: Always check the torques at every condition inspection. Check torques multiple times during your first 25 to 50 hours.

Karl

My RV-8 was recently purchase already flying. It was licensed in 2001 and I don't think maintenance has been attended to very well. We just torqued the bolts and each one took about a turn to come up to spec.

There's another thread on the subject here: http://www.vansairforce.com/community/showthread.php?p=163808&posted=1#post163808

Modified a socket that is doing the job. I'll post a picture when I find my camera! The socket is a 3/8" drive 12-point short socket that I cut 3/16" off of the "nut" side and ground a large flat off the side of the square end.

I'd like opinions on this idea I posted in the other thread:

"I tend to look for corrections to root problems rather than cobbling up 'work arounds' like modified wrenches or sockets. It seems to me that the root of the problem is the ridge that blocks access to the nuts. Another IA buddy looked at the nuts and suggested using a slightly longer bolt and two additional washers to raise the nut so it is accessable with a wrench.

Since the bolt is in shear not bending I think it's a structurally sound idea. Any comments? BTW I'm a mechanical engineer so have some good education and experience to draw on but know the value of getting opinions from other knowledgeable people."

Any comments?

Tool for nuts on landing gear bolts on RV-8

I had a heck of a time torquing the landing gear bolts on my -8 at the condition inspection. I don't think they had ever been checked (I bought the plane already flying). I was able to get an open end wrench onto three of the nuts but could not get a good grip on the fourth one. Here's a picture of the offender. It is the front bolt on the right side of the airplane. (note: 1/18/09 relinked photos. This photo now shows the took on the bolt.)



Here is a picture of the modified socket and associated tools that I used to torque the last landing gear bolt on my RV-8. You can click on the images to see a larger picture.



The socket is Craftsman 3/8" drive 9/16" 16 point socket. It's an old one leftover from a partial set someone gave me. I used it because it seemed to have the thinnest wall section. I modified it in two ways:

1) the 16 point end that slips over the nut has been shortened. The entire socket is now just 3/4" long

2) one side has been ground off parallel to the 3/8 drive so there is only 1/16" wall left.

The other parts are two lengths of 3/8" bar stock. I made two lengths because I did not know what length would work best. The shorter one is 1-1/2" long and the longer one is 2-1/2" long. The shorter one worked best. You need to slightly round the corners of both pieces so they will slide into the socket easily but not too loosely.

Here's how it works. Reach into the tower and position the socket on the nut with the flat facing forward. Whoever is under the plane with the torque wrench may need to turn the bolt a little so everything fits into place well. Then put the square stock into the 3/8" wrench. Mine was a tight fit which was great because I could use the wrench to position the square stock. When everything is in place the square stock is well under that upper ridge and is in line with the bolt, and the socket is flat over the nut.

One everything is in place, hold onto the wrench and have the other person tighten the bolt to the proper torque.

I have not tried the socket on any of the other bolts but will next October when the condition inspection is due. I've also ordered some replacement nuts and extra hardened washers to replace the nuts I busted the knuckles on with the open end wrench. I'm also considering ordering longer NAS bolts and making a hardened steel spacer so the nut sits up higher. That way all four could be easily held with a wrench and I would not need the socket. (1/19/09 update - the tool works great on all 4 nuts but the short length of bar stock works best in most cases.)

This is one area Vans could redesign and make it much easier to get at to torque these important bolts. All four bolts took at least 1/2 a turn before reaching torque! I wonder how many other -8s are out there in that condition?

new tools

I always like new tools. When I checked mine I found again what most others are finding. Maybe a quarter turn.
I could get a wrench on all but the left rear. Had to use screwdriver, wrench and body language to get that one.
I think your ground socket and square stock will work nicely on that one next time.

Glad I could help. The socket mods had been suggested by others but the square stock was perhaps a new twist. Someone else has probably done that before too.

Good luck.