Landing gear seals and springs

A

Abisceglia

New member
All, apologies if this has been asked and answered in previous posts but I couldn't seem to find a difinitive answer. I've got my 14-13-3 up on jacks and the gear apart to replace the springs and seals. My manual references "packing glands" for the strut?? Is there a modern seal ring upgrade for this, or what do I use? There was nothing in the tube. Also can anyone tell me what the free state spring length should be and where I can source some?

Cheers,
 
The original LG packing are chevron (or vee) seals. They may be available at a local hydraulic shop or an on-line supply house or McMaster-Carr.

I have an ancient Bellanca 14-13 illustrated parts doc but it only shows a drawing reference #. That's no help for finding size, etc.

I searched this forum for "packing" and got enough results for a month of research, but nothing helpful yet. Everything bit of info needed becomes an Easter egg hunt. Maybe somebody will ....

Ron
 
I haven't responded to your request that was delivered through Robert....no excuse.
If you have a 14-13-3, you do not use the chevron packings as used in the earlier airplanes. You have the same shock strut as the 14-19 series.
It is different. You use "O" rings instead of packings. I believe the spring is the same but it's in a different location than the earlier airplanes. I'll try to get you the free length of the spring and the p/n of the "O" ring.
Dan
 
I've posted in the past about the Chevron "V" packings. I don't know why people have such a hard time finding them. Most hydraulic supply shops have them or can order them. I have supplied probably ten sets for the MLG and TW over the years.
The size for the MLG packings is 2 1/2"X 1 7/8." You'll need 6-7 "Vs" plus a male and female for each side. The TW packing is 1 3/8"X 1." I remember 6 Vs with a male and female for the top and bottom.
The free length for the new MLG spring is 6." The TW spring is lighter wire but longer at 7 3/8." The springs are the same for the 14-13 and 14-19 series.
Dan
 
Thanks so much for the feedback and measurements. As simple as it would seem, finding these chevron packings or "O" rings has not been easy. I've been to 3 hydraulic shops and two wouldn't even bother trying to source replacements. The 3rd one is still looking..
I can't seem to post pics but the wiper is definitely fiberous like felt. There was nothing else present but evidence that some sort of seal was there at one time. I've got the same assembly drawing, useless.
 
Well the only hydraulic shop that was willing to help is stumped. The sizes provided here are not correct for my gear... 2 1/2” is the outside diameter of my strut so that can’t be the size of the v’s. The seal groove is only around 3/16” wide. Can anyone offer any more input, or better yet replacements!!??
 
Well I'll start off by thanking all that replied for your help. Unfortunately I still am nowhere with this. Local hydraulics shop could not source replacement parts. I picked up the MS28775 O rings that Larry Mentioned from aircraft spruce and the 330's are as big as the outside diameter of my strut so they are wrong, at least for my gear. I have a gear up/down switch and a motor to extend and retract the gear, so I'm assuming I have a 3. Perhaps the gear is not from a 3?? I just don't understand why this is so difficult. Same with the bloody taxi springs, I've got some spring company specially making them for stupid money because no one can locally source em. :cry:
 
Andrew: I see that your Cruisair is in the Owner Maintaned category, somewhat like our experimentals are here. Is it possible that the previous owner(s) modified it or replaced it from another model?
 
Robert,
That's what I suspected so I went through the maintenance logs again but could find no record of any modifications.
If anyone reading this has taxi springs or any info on packing glands replacement, please let me know.
Regards
 
Why don't you send us some photos of your upper and lower gear leg tubes. -3 and Cruisemaster gear parts are visually different from the earlier gear legs. It's hard to help if we don't know what we are dealing with.
You mentioned you were having springs made....I had a local spring shop make the gear springs to spec and they subbed the job to Canada. the cost was about $80-$85.
 
Hi Dan I’d love to attach pics but I keep getting error messages when I try, what do I need to do to get pics uploaded? Failing that, I’d be happy to send them via email. My bird is a 1948. I understand that up to and including 1948 the struts were straight they did not open up wider at the end like later models. There is a packing or sealing washers midway down the strut and one at the mouth. Looks like compression packing is available at McMaster Carr, but I’m at a loss for what goes down inside the strut.
 
Well you have the info on the struts backwards. What is the s/n of your airplane?
You can email me at: dhcullman@aol.com.
Dan
 
Abisceglia said:
Hi Dan I’d love to attach pics but I keep getting error messages when I try, what do I need to do to get pics uploaded? Failing that, I’d be happy to send them via email. My bird is a 1948. I understand that up to and including 1948 the struts were straight they did not open up wider at the end like later models. There is a packing or sealing washers midway down the strut and one at the mouth. Looks like compression packing is available at McMaster Carr, but I’m at a loss for what goes down inside the strut.
Click to expand...
Which one of the two types of struts you describe do you have? That would help.
r
 
Gents,
I contacted an ex-member here Dave Reid and provided me with the contact information of a Bellanca owner locally, a 2.5 flight from me. A friend and I flew out to to see him yesterday. This gentleman is Wayne Kemmit, and he has rebuilt a beautiful example of a Cruisair. He was very gracious agreeing to pick us up from the local airstrip and to share his handy work and hangars. He also just happened to have two spare MLG in his inventory which he reluctantly agreed to sell to me! So, I’m going to rebuild these and I imagine that worst case scenario will have have the original seals in them for me to replace. Alternatively I will be able to use the seals that Dan referenced. Robert and Dan, I’ll send pics in the emails you provided. Thanks so much for your continued help and patience!

Pictures of my current gear: View attachment 1 View attachment 2
 
Andrew,
S/N 1607 was built as a 14-13-3. You have the correct gear legs for that model. As I stated earlier in an email, the parts to overhaul should be available from Alexandria Aircraft, as they are the same parts used in the Cruisemaster.
Dan
 
Just my 2 cents worth on this subject. As the picture of the upper strut clearly illustrates, the wiper gland seal is retained by a large metal ring which in turn is secured by peening over or staking the end of the strut. When I first became aware of this “design concept” I really couldn’t believe this came out of the factory this way, but this was in fact Bellanca’s crude solution. Years later in the Viking era the design was changed to use a snap-ring to retain the wiper seal. Not being satisfied with hammering on the upper strut I came up with a method to machine the snap-ring groove into the strut ID which allows me to correct what I consider to be an inferior design feature. Another point… you are likely to have a combination of grease and hydraulic fluid coating the moving surface of the inner strut. The wiper seal does not do an adequate job keeping the strut clean unless the OD of the strut is well polished. Re-chroming the strut is the way to go, but it costs. Also, having dis-assembled the landing gear from several aircraft I have found some instances where a felt ring was stacked next to the rubber wiper seal which seems to make sense to me, however I cannot find any reference to this in any of the parts manuals. AAC does have all of the parts as Dan mentions, including the bronze bushings if you really want to go all out on the rebuild. However I am not satisfied with the tolerance stack ups between the ID of the bushings and the OD of the lower strut, so I have chosen to make my own to reduce the amount of play once assembled. Keep us posted on the outcome! --Rob
 
Idea. (MY 2 cents) On the later style gear, why not use only thread lock to retain the seal? If the seal is a snug fit on the tube ID, thread lock would hold very well. The seal could be longer - dual wiper, etc. It might be possible to have it protrude slightly. Some longer seals can accommodate more lateral shaft movement( worn bearing). The choice of seals would be greater as well. And since the installed seal is very accessible, future remove and replace would not be a particular challenge - even if a very strong thread lock was chosen. Just a thought.

ron
 
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