tailwheel spring installation

How to keep the Cessna 170 flying and airworthy.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

buzzlatka
Posts: 168
Joined: Thu Feb 16, 2006 11:39 pm

tailwheel spring installation

Post by buzzlatka »

I am replacing the tailwheel spring on my 52b with a new one from univair. (univair Part # U170ab). I looked at the parts catalog and bought all the normal nuts and bolts to replace the old ones. I already have the L-19 eyebolt to attach the tailwheel to the spring.

My question is this. In addition to replacing old nuts and bolts, is there any other gotchas I need to be aware of?

I read somewhere about a sharp edge on the leaf spring that needs to be dealt with but couldn't figure out what to do to the edge.

Anyone have a basic gameplan for the replacement. I know the one main bolt that attaches the leaf spring to the tail need to be removed. Also the u bolt and u shaped bracket. Do I need to remove the tailwheel spring retainer part #0510000-31 or will the leafs just slide out?

Thanks
User avatar
canav8
Posts: 1006
Joined: Thu Sep 25, 2008 2:34 pm

Re: tailwheel spring installation

Post by canav8 »

buzzlatka wrote:I am replacing the tailwheel spring on my 52b with a new one from univair. (univair Part # U170ab). I looked at the parts catalog and bought all the normal nuts and bolts to replace the old ones. I already have the L-19 eyebolt to attach the tailwheel to the spring.

My question is this. In addition to replacing old nuts and bolts, is there any other gotchas I need to be aware of?

I read somewhere about a sharp edge on the leaf spring that needs to be dealt with but couldn't figure out what to do to the edge.

Anyone have a basic gameplan for the replacement. I know the one main bolt that attaches the leaf spring to the tail need to be removed. Also the u bolt and u shaped bracket. Do I need to remove the tailwheel spring retainer part #0510000-31 or will the leafs just slide out?

Thanks
Buzz there is no magic other then it is better to remove and install the spring stack assembled when installing into the tail bracket. If you are only replacing the main leaf spring only and not the entire stack then the burr that is generally located on the bottom of the leaf spring that is located immediately above the main spring is not a problem. The burr that they are talking about is caused from when they sheer the spring to length, it leaves a small burr. It should be filed flat as to not marr the main spring. This sounds like a rookie statement but "Make sure that the spring stack is all the way seated in the bracket before putting the main bolt in the tail." I have seen guys not seat the spring in the bracket and then loose the tail spring. Also, it is a good idea to check to make sure the clamp the goes around the spring stack is secured with the upper and lower part (2 parts) around the stack. This is to protect the steering chain from getting caught in the bottom side of the stack during operation. That is about all there is. I am sure someone else may chime in but I have done a couple and you might cuss a little getting the stack in but thats all. Good Luck. Doug
52' C-170B N2713D Ser #25255
Doug
User avatar
GAHorn
Posts: 21052
Joined: Fri Apr 12, 2002 8:45 pm

Re: tailwheel spring installation

Post by GAHorn »

Good words, Doug!
BAsically, just take a file and/or emory and put a "radius" on the lower/aft edge of the spring just above the mainspring, so as to reduce the possibility of that sharp edge from creating a "stress riser" on the main spring.

When removing the spring stack, relax all those AN3 bolts/nuts on the top plate and remove the U bolt and channel, remove the main attach bolt from beneath, and then slide it all out together. You can then remove the tailwheel from the mainspring. (Of course, the first thing you did was unclip the steering chains.) :lol:

Reverse the procedure.

Good words: Consult your Illustrated Parts Catalog before/after to prevent incorrect assembly.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
User avatar
DaveF
Posts: 1522
Joined: Sat Nov 03, 2007 1:44 am

Re: tailwheel spring installation

Post by DaveF »

Put a C-clamp on the spring stack before removal, and again before reinstallation. Then the pack slides in nice and easy. Also, as George said, loosen the AN3 bolts. I posted my observations on this job here and here.
buzzlatka
Posts: 168
Joined: Thu Feb 16, 2006 11:39 pm

Re: tailwheel spring installation

Post by buzzlatka »

Thanks guys, i'm replacing it in the morning. This really helps.
buzzlatka
Posts: 168
Joined: Thu Feb 16, 2006 11:39 pm

Re: tailwheel spring installation

Post by buzzlatka »

What a difference a new spring makes! Here you can see the old spring sagging big time and the new spring looking good. I did realize that I put the tension springs and chains on backwards when I took the new pic. They have been corrected.

old spring
Image

New spring
Image
User avatar
canav8
Posts: 1006
Joined: Thu Sep 25, 2008 2:34 pm

Re: tailwheel spring installation

Post by canav8 »

Congrats Buzz!
52' C-170B N2713D Ser #25255
Doug
User avatar
Bikini
Posts: 47
Joined: Tue Jun 29, 2010 6:30 pm

Re: tailwheel spring installation

Post by Bikini »

I'm about to do that same thing.......I'll take pics..........lets have a contest to see who's was worse.........just wait!!!! ha

Bikini
Bikini
High Point NC
F-16, B727, A300, C170B
richard d miller
Posts: 5
Joined: Thu Aug 11, 2016 1:51 am

Re: tailwheel spring installation

Post by richard d miller »

Hi folks I'm new because just purchased a 53'. So how/where do I get the new hardware to put in after I replace my tailwheel spring? I know where to get the AN stuff but the brackets, spacers, bushing etc.? Oh note here: they want 750.00 for the 0510000-36 bushing. Luckily it wasn't in stock.....and no luck finding any of the stuff with Cessna numbers..... Thx much
richard d miller
Posts: 5
Joined: Thu Aug 11, 2016 1:51 am

Re: tailwheel spring installation

Post by richard d miller »

Hey guys.... two quotes for the 051000-36 bushing: 850.00???? Univair and Cessna.........
User avatar
sfarringer
Posts: 310
Joined: Wed Jan 12, 2005 10:49 pm

Re: tailwheel spring installation

Post by sfarringer »

Are you replacing that bushing because it is severely worn, or just because?
I would only replace that bushing if the condition warranted it.
Ragwing S/N 18073
User avatar
lowNslow
Posts: 1530
Joined: Mon Apr 22, 2002 4:20 pm

Re: tailwheel spring installation

Post by lowNslow »

richard d miller wrote:Hey guys.... two quotes for the 051000-36 bushing: 850.00???? Univair and Cessna.........
I'm guessing that it is standard 3/8"ID x 1/2" OD bushing material. You should be able to find this online or at a bearing shop.
Karl
'53 170B N3158B SN:25400
ASW-20BL
User avatar
GAHorn
Posts: 21052
Joined: Fri Apr 12, 2002 8:45 pm

Re: tailwheel spring installation

Post by GAHorn »

Unless you've lost that bushing I can't imagine needing to replace it. There is virtually no wear that occurs on it.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
User avatar
Kyle Wolfe
Posts: 706
Joined: Mon Mar 17, 2003 12:30 am

Re: tailwheel spring installation

Post by Kyle Wolfe »

Saw this on the super cub site. Sounds as though the developer is working on the STC.

http://www.supercub.org/forum/showthrea ... Suspension
Kyle
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
User avatar
n2582d
Posts: 2834
Joined: Mon Apr 29, 2002 4:58 am

Re: tailwheel spring installation

Post by n2582d »

For those of us not members on the Supercub website I'm guessing this is the picture we can't view. I also see the horizontal stab attach fitting that Bill is needing there!
image.jpeg
Gary
Post Reply