New Tailwheel Leaf Springs too thick

How to keep the Cessna 170 flying and airworthy.

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thejetjerk
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Re: New Tailwheel Leaf Springs too thick

Post by thejetjerk »

The issue still exists, the spring set I purchased from Univair last month (March 2021) would not fit. My Ap/IA spend a lot of time dealing with it. :(
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c170b53
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Re: New Tailwheel Leaf Springs too thick

Post by c170b53 »

Might he have tried just replacing a new main leaf with the old spring set ?
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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thejetjerk
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Re: New Tailwheel Leaf Springs too thick

Post by thejetjerk »

Once I was aware of the issue, I gave my IA the option to use just the main leaf from the set, but he has already managed to get the new spring set to fit.
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GAHorn
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Re: New Tailwheel Leaf Springs too thick

Post by GAHorn »

It is virtually impossible....that the entire spring-set needs replacement. The only spring which can fail to hold the tailwheel to the airpalne...is the ONLY spring that is attached to the tailwheel..... and that is the MAIN (lowest) spring.

It is more likely to cause damage to your airplane by forcing-fitting en entire spring-stack than it would to only replace the one spring which really matters in this.
'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. ;)
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dstates
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Re: New Tailwheel Leaf Springs too thick

Post by dstates »

GAHorn wrote:It is virtually impossible....that the entire spring-set needs replacement. The only spring which can fail to hold the tailwheel to the airpalne...is the ONLY spring that is attached to the tailwheel..... and that is the MAIN (lowest) spring.

It is more likely to cause damage to your airplane by forcing-fitting en entire spring-stack than it would to only replace the one spring which really matters in this.
I think all 4 of mine needed to be replaced :wink: Maybe I could have kept the smallest one.

My tail had the old bracket so I could handle the thicker springs.
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leaf_springs.jpeg
N1235D - 1951 170A - SN: 20118
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mmcmillan2
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Re: New Tailwheel Leaf Springs too thick

Post by mmcmillan2 »

Yea, they dun wore out. Is that a tail tie down eyelet?? Where’d ya get it from?
170B owner, KCFD, CFI(I), ATP Multi
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dstates
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Re: New Tailwheel Leaf Springs too thick

Post by dstates »

mmcmillan2 wrote: Is that a tail tie down eyelet?? Where’d ya get it from?
Yes, good eyes. It is from Air Repair (their info below). I ended up not using it because I have a Maule tailwheel and it doesn't fit (either orientation) with the cap on the top of the tailwheel (red circled area in picture). I think it only really works with the Scott tailwheel. I think it was $20+ for the part and another $15-20 for shipping.

Air Repair, Inc 662-846-0228, L-19 PN 0642105, https://www.airrepairinc.com/cessna-l-19.html
maule_tailwheel.jpg
N1235D - 1951 170A - SN: 20118
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GAHorn
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Re: New Tailwheel Leaf Springs too thick

Post by GAHorn »

dstates wrote:
GAHorn wrote:It is virtually impossible....that the entire spring-set needs replacement. The only spring which can fail to hold the tailwheel to the airpalne...is the ONLY spring that is attached to the tailwheel..... and that is the MAIN (lowest) spring.

It is more likely to cause damage to your airplane by forcing-fitting en entire spring-stack than it would to only replace the one spring which really matters in this.
I think all 4 of mine needed to be replaced :wink: Maybe I could have kept the smallest one.

My tail had the old bracket so I could handle the thicker springs.
I stand corrected. Your previous spring stack was clearly abused above/beyond the ordinary and should have been replaced even earlier.

My previous comment was made thinking of our recommendation for 500-hour preventive maintenance in ordinary use ... :wink:
'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. ;)
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dstates
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Re: New Tailwheel Leaf Springs too thick

Post by dstates »

GAHorn wrote:
dstates wrote:
GAHorn wrote:It is virtually impossible....that the entire spring-set needs replacement. The only spring which can fail to hold the tailwheel to the airpalne...is the ONLY spring that is attached to the tailwheel..... and that is the MAIN (lowest) spring.

It is more likely to cause damage to your airplane by forcing-fitting en entire spring-stack than it would to only replace the one spring which really matters in this.
I think all 4 of mine needed to be replaced :wink: Maybe I could have kept the smallest one.

My tail had the old bracket so I could handle the thicker springs.
I stand corrected. Your previous spring stack was clearly abused above/beyond the ordinary and should have been replaced even earlier.

My previous comment was made thinking of our recommendation for 500-hour preventive maintenance in ordinary use ... :wink:
Yeah, I figured I had you with that one. George... :D Replacing those springs was one of my very first repairs on my plane (shortly after replacing a couple tires and tubes).
N1235D - 1951 170A - SN: 20118
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N3454C
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Re: New Tailwheel Leaf Springs too thick

Post by N3454C »

I am planning to replace my tailwheel spring group I purchased from Univair in a few weeks on my '54B model. The IPC shows a couple rubber "pads" (cessna P/N 0442119-1). My concern is (assuming they are original) they should be replaced. I can not find them anywhere for sale. How have others dealt with these pads during leaf spring replacement? Any advise? Thanks.
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GAHorn
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Re: New Tailwheel Leaf Springs too thick

Post by GAHorn »

N3454C wrote:I am planning to replace my tailwheel spring group I purchased from Univair in a few weeks on my '54B model. The IPC shows a couple rubber "pads" (cessna P/N 0442119-1). My concern is (assuming they are original) they should be replaced. I can not find them anywhere for sale. How have others dealt with these pads during leaf spring replacement? Any advise? Thanks.
Eric…don’t you have a 170-B model? …with the large, aluminum “alligator” tailwheel bracket..?? If so, your tailwheel assembly does not use those pads.

Perhaps you might wish to review the tailwheel bracket Service Kit Instructions: viewtopic.php?f=40&t=9442
'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. ;)
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N3454C
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Re: New Tailwheel Leaf Springs too thick

Post by N3454C »

Perfect! Yes, that looks more like it! I will review the service letter, but looks good! thanks!
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redacted
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Re: New Tailwheel Leaf Springs too thick

Post by redacted »

Just installed a new Univair spring set. Bolted up no problem.
Nathaniel Perlman
1952 170B
N2282D S/N 20434
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N3454C
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Re: New Tailwheel Leaf Springs too thick

Post by N3454C »

redacted wrote:Just installed a new Univair spring set. Bolted up no problem.
Sounds good! planning to do mine next weekend. I hope to have the same results~
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BrianW
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Re: New Tailwheel Leaf Springs too thick

Post by BrianW »

I have a 55B, and purchased a new main spring U0542106 from univair. My mechanic also said it's too thick to put in with the rest of the stack. If I go ahead and buy the whole pack, will that fit correctly or fit by installing only 3 of the springs?

-Brian
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