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Nose Landing Gear Play

Bart

Well Known Member
Hey guys, I've been flying my -10 for 4 years now. I finally replaced the nose tire and noticed when I had the nose off the ground that there was some play in the landing gear....not a whole lot but enough to make me check all the bushings. I don't normally lift the leg up but when I checking torque's and generally inspecting the nose wheel area I lifted the gear leg and found very slight vertical and lateral movement. The plans don't mention play limits and its been too long since I first installed the gear to remember if I had it from new or not. The bushings were fine and the gear shows no wear...I'm thinking I may be over thinking this but was curious if others noticed this when new because I can't remember.
 
If your nose gear has vertical motion when it is unloaded, it simply means the rubber shock "donuts" have compressed. Vans provided, with your kit, extra washers to be used and installed just for this reason. The washers are installed at the top end of the shaft under the "top hat". I am sure you can obtain these from Vans.
If you have lateral movement, I would check the bushings at the gear leg pivot points.
 
The rubber donuts do settle in a bit, that may be the source of your up/dn movement.

See page 46-7, upper right hand, second paragraph (I think it is) discusses adding a second u-1002 washer after the donuts settle.
 
Totally forgot about those washers. I'll dig those out tomorrow. In the mean time I have replaced all the bushings however there was no apparent problem with any of them. Thanks for memory jog.
 
Sorry for the necropost, but this is the only thread that mentions the appropriate part number. What are the U-1002's made from? I have a total of 4 aluminum washers that would seem to be the right parts, but they don't have a part number.
 
Sorry for the necropost, but this is the only thread that mentions the appropriate part number. What are the U-1002's made from? I have a total of 4 aluminum washers that would seem to be the right parts, but they don't have a part number.

Those are the ones. Stamped out of aluminum sheet stock. De-bur before install.
 
Check your bushings

I still had considerable play in the nosegear leg after properly compressing and preloading the elastomer discs. This turned out to be because of the sloppy fit of the VA 143 ans VA144 bushings in the nose gear link and engine mount weldments. I ended up turning some new bushings that fit better but Vans also sells oversize bushings to fix this problem. The VA143 bushing fit was poor enough to make me think the elastomers were loose at first because of the vertical play in the gear leg.
 
On a related note, I have one of the aluminum washers installed under the WD-1015 (that's the cap on top of the shock strut), and am struggling to compress the donuts far enough to install the bolt which secures the WD-1015.

At this point, the main gear is off of the ground and the airplane is supported by the engine hoist lifting the very front of the nosegear strut and by sawhorses under the tail. In other words, I have maximum mechanical advantage to compress the donuts.

Despite that, I cannot compress the donuts far enough to install the bolt through the WD-1015. Eyeballing it, I need to compress the donuts another 1/8" or so. Even with me doing a pull-up on the engine mount to add more weight, I'm not getting there.

Since a few hundred folks have already solved this problem, there must be a better answer.

Suggestions?
 
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Washers

How many washers are you trying to put in? When I did mine, only one would come close to fitting. With the engine mounted, I pulled down on the mount using body weight, and the bolt went right in...
 
I believe someone posted about a ratchet strap around prop hub and gear leg to compress enough for bolt to slip in.
 
When I fitted the SB plate, I had great difficulty getting the bolt in. I finally realised that the "top hat" had not gone fully down on its stem. A technical tap fixed it.......
 
When I fitted the SB plate, I had great difficulty getting the bolt in. I finally realised that the "top hat" had not gone fully down on its stem. A technical tap fixed it.......

That technique came in handy for me too. I'd have sworn it was seated, but no.

Thanks for the tip.
 
Nosewheel leg slop

I still had considerable play in the nosegear leg after properly compressing and preloading the elastomer discs. This turned out to be because of the sloppy fit of the VA 143 ans VA144 bushings in the nose gear link and engine mount weldments. I ended up turning some new bushings that fit better but Vans also sells oversize bushings to fix this problem. The VA143 bushing fit was poor enough to make me think the elastomers were loose at first because of the vertical play in the gear leg.

Paddy, I wish I had seen this post before I bought all three bushings new from Vans only to find out they were the same size as the old ones (no wear) There is still vertical slop in the nosegear leg from the loose fitting bushings. This movement adds a pounding effect to the bolt with each landing that is transferred to the weakest link, the welded on bracket that attaches all this to the nosegear leg. It will eventually elongate the holes requiring welding or replacement of the gear. Did someone say that Vans has oversized bushings that actually fit properly? Why would they still use the undersized ones at all?

Mark, new RV-10 owner.
 
Paddy, I wish I had seen this post before I bought all three bushings new from Vans only to find out they were the same size as the old ones (no wear) There is still vertical slop in the nosegear leg from the loose fitting bushings. This movement adds a pounding effect to the bolt with each landing that is transferred to the weakest link, the welded on bracket that attaches all this to the nosegear leg. It will eventually elongate the holes requiring welding or replacement of the gear. Did someone say that Vans has oversized bushings that actually fit properly? Why would they still use the undersized ones at all?

Mark, new RV-10 owner.

Do you know for sure that the sockets the bushings go in haven't worn at all?
They should be lubricated occasionally.... maybe yours never have been.
There is also a tolerance to both parts (the socket and the bushing). Add to that a slight amount of wear and you can have what appears to be a lot of play if you take into account the long length of the gear leg.
 
Play in new nose gear

I have play in my nose gear bushings and they have never been down a runway. I am having a friend who owns a machine shop make me bushings with very close tolerance.
 
Kyle,

Use a ratchet strap between the nose gear and your motor mount or possibly even over the top of the motor (if you have a decent spot to put load on it without damaging anything). With a few cranks on the strap, you can get enough compression to slide the bolt through.

Phil
 
Slop

I just did my condition inspection and have the slop from the VA-144 bushing. For me, it appears to be the pilot side bushing since the play is vertical and to the passenger side. I spoke to Vans about this and they could only give me specs on the minimum and maximum difference between the bushing outer diameter and weldments inner diameter. For reference, here are the numbers so you can check yours against these:

Max difference between OD of bushing and inner is 0.016?, minimum of 0.004?

I?m probably going to order the oversized bushing and have a machine shop turn it down.
 
Bushings

I think what we have here is a question of serviceable vs optimal in terms of fit. I would guess that primary reason the original bushings provided with the kit are somewhat undersized is to account for production tolerances in the weldment socket. My observation was that that socket within which the bushing fits isn't perfectly round, some are more round than others and none of them are reamed after welding, so there's always going to be a variance in fit (and wear for that matter) because of that. An undersized bushing will fit them all without having to up the tolerance on the weldment. In my plane, the slop was more than I was comfortable with, so I made my own bushings to improve the fit. There's still clearance for the lubricant interface, but the clunking in the nosegear when lightly loaded is greatly reduced (as is the impulse loading that accompanied the clunking). Incidentally, I only replaced 2 of the 3 bushngs, the 3rd was close enough to leave it alone. For what it's worth, I also replaced some (not all) of the bushings in the flight control linkage because of the same variance in fit.
 
Ratchet Strap

It has been suggested a number of times to use a ratchet strap to pull the nose gear up to compress the elastomer discs and insert the top cap bolt. This makes sense, but the amount of compression applied can very easily be overdone (ratchet straps can be quite powerful!). Consider that if you want the maximum amount of travel and cushioning that was designed into the system, you'll want to compress the elastomers just enough to eliminate free play and no more. In my build, there was easily be enough compression on the discs with the normal weight of the engine plus a moderate pull down on the prop by a helper to get the bolt in. If there's more force than that required, there might be too many washers in there, especially after installing the elastomer plate doubler from the bulletin... Of course if you don't have a moderately calibrated helper, a strap might be a good option ;-)
 
VA-144 OVSZ Bushes

My Nose Landing Gear has always had some side to side play in it so this Annual I took the opportunity to install the Oversized Bushes that Van's sells.

2 x VA-144 OVSZ

The bushes come oversized and a simple measurement with some telescopic bore gauges will give you the correct size to machine your new bushes down to.

The Standard Bushes VA-144 measure : .750"

My Engine Frame/Nose Gear Mount measured : .760 ( average )

So I machined my new bushes to .758 ", applied fresh grease and reassembled.
I was rewarded with no detectable side play in my Nose Gear and an annoying clunking that was always there when I taxi or roll out after landing is now gone.

I don't know if the old bushes would of ever become a service problem but I am enjoying the reduction in play and noise in my front nose gear.

It should be noted that all these bushes require some service (grease ) and I would recommend that all owners plan to service these bushes at some time, maybe every 4-5 years.
 
With much thanks to Ashley whose post above describes exactly what we did, with ours being machined to 0.759" all i can say is wow.

Tracks much nivcer, not clunky all the time and flies about 30 knots faster :p

Seriously well worth getting this right.
 
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