Replace Rear Seat Bolts

How to keep the Cessna 170 flying and airworthy.

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MoonlightVFR
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Joined: Sun Jan 02, 2005 5:55 pm

Replace Rear Seat Bolts

Post by MoonlightVFR »

I have read post about removing original bolts and replacing w Clinch pins secured w hitch pins.

Would like the convenience of 2 PC rear seat removal.

Can someone help me with the exact size of parts needed ? Source will be ACE aerospace.
I see part AN 394-33/MS0392-3C 33 But I don't know how convey to clerk.

20 miles from airplane and would like to accomplish in one trip.

Need to know length and diameter of clinch pin in inches.

Regards
gradyb, '54 B N2890C
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brianm
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Re: Replace Rear Seat Bolts

Post by brianm »

I used, from Spruce:
AN394-33 CLEVIS PIN MS20392-3C33
04-05100 COMMERCIAL STEEL WIRE LOCK PIN
Brian M
N2669V - '48
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Bruce Fenstermacher
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Re: Replace Rear Seat Bolts

Post by Bruce Fenstermacher »

It is a 1/4 pin that is 1-1/32 long. I don't know that I used one that exact length. It is was a pinch longer or shorter, you'll probably be OK. I'd favor a slightly longer if you have to because the extra length will not be seen as it is inside your seat back and it won't effect the way it works. Your ACE place will have something like this pin in the Hillman Hardware selection.
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Bruce Fenstermacher, Past President, TIC170A
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gfeher
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Re: Replace Rear Seat Bolts

Post by gfeher »

Grady, the only thing I would add to what has been said already is to suggest that you also get some pins a little longer and a litter shorter than what's been described. I changed my rear seat back bolts to pins during my first annual. Almost every time I remove and reinstall the seat back, at least one of the pins I used the last time seems a little too long or a little too short this time. I'm not sure why. But after struggling with it for a few years, I've stopped fighting it and now just keep 2 or 3 lengths handy, and use the ones that fit best at the time. They are cheap enough.
Gene Feher
Argyle (1C3), NY
'52 170B N2315D s/n 20467 C-145-2
Experimental J3 Cub Copy N7GW O-200
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ghostflyer
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Re: Replace Rear Seat Bolts

Post by ghostflyer »

Not wishing to steal some ones thunder on this one “but” how legal is it to replace hardware securing a seat to the aircraft and what sort of log book entry would be made ?
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Kyle Wolfe
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Re: Replace Rear Seat Bolts

Post by Kyle Wolfe »

I keep looking for the linch pin style (push button to T handle with the little balls that retract) so I'm not always trying to replace the small keeper hairpin that's inserted through the clevis hole which I cannot see.

Been googling but just not yet found the proper size......
Kyle
54 B N1932C
57 BMW Isetta
Best original 170B - Dearborn, MI 2005
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GAHorn
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Re: Replace Rear Seat Bolts

Post by GAHorn »

ghostflyer wrote:Not wishing to steal some ones thunder on this one “but” how legal is it to replace hardware securing a seat to the aircraft and what sort of log book entry would be made ?
That hinge pin does not secure the seat to the aircraft. It secures the seat back (a non-structural part) to the seat. Any common AN pin or bolt hardware solution would also work as a minor alteration.
'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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