Easiest way to put in the back seat.

[cfiatzph]

My A/C has nutplates every where floor and side connections for the rear seat. What is the trick to installing the rear seat, or is there none? Thanks
Just trying to make this go easier!

Thanks

[GAHorn]

That rear seat is such a pain to remove/reinstall that I have refused to do it since 7 years ago when it was last done.
Replacing the hinge-bolts (AN3's) at the hinge of the seat back is the most important improvement you can make. (Use a MS clevis instead for a minor alteration.) That way you can actually manipulate the seat without too much trouble.
The front, middle leg/support uses a single AN3 bolt down thru the floor to nutplate, the rear uses a single AN4, and each side uses a AN3 to bolt to the side-bracket.

So.... undo the two side bolts, the front and rear leg bolts, and the seat will be loose from the floor.
Next, remove the seat-back hinge-bolts to disconnect and remove the seatback and take it out of the plane. The seat-bottom may now be manipulated out of the airplane. (Careful about scratching up the doorposts.

Hint: I found it helpful to begin this entire process by FIRST removing the machine screws which hold the armrests for the rear seat, and temporarily removing the armrests. Those screws hold he armrest from the outside of the fuselage.

Don't do what I did, and forget to replace those lousy AN4-11A bolts (seatback hinge) with clevis pins. (AN394-39)


Install them with the HEAD toward the center of the airplane....clevis pointing outboard...so you can remove them. NOT the way the factory did the bolts. (Or another solution is to simply us drilled AN4-11 bolts with a washer and cotter (rather than undrilled -11A bolts).

[jrenwick]

The question was actually about how to install the seat, not take it out. I always find the hardest thing is to get all four screws started into the nutplates in the floor and side structure. I try to get the threads started on all four of them before I tighten down any of them. Sometimes it seems to work better if you start the ones in the floor first; other times starting the side ones first works better. It just takes quite a bit of wiggling and jockeying to get them all in. First make sure the threads on your bolts are in good shape -- use new bolts if necessary, and maybe clean out the nutplate threads now and then. A little lubrication might help too. There isn't any magic that I've heard of, although having the seat back off probably helps!

[Bruce Fenstermacher]

Yes with the seat back hinge modified as George described so that you are only working with the seat bottom and then the back the whole process is much easier.

I use an awl to line everything up. The AN bolts also have a point ground on them to help line them up and start them. I use 1/4" drive socket that I can put pressure on the bolt and push it in as I turn it.

[Robert Eilers]

I have gotten pretty good at removing and reinstalling the rear seat (this after poking a very expensive hole in the overhead the first time). The clevis pin suggestion is something I am going to follow up on. The side bolt holes on my rear seat do not line up with the threaed holes in the side of the airframe any longer. Apparently, over the years the rear arn has been bent downward. One of the first things I noticed, the first time I removed the rear seat, was that a new hole had been drilled in the lower bar to accomodate a more aft location of the forward bolt. I am not sure just how to fix this problem. I have considered trying to rebend the rear attachment bar, but hesitate to do so for fear of breaking it off altogether.

[GAHorn]

I have gotten pretty good at removing and reinstalling the rear seat (this after poking a very expensive hole in the overhead the first time). The clevis pin suggestion is something I am going to follow up on. The side bolt holes on my rear seat do not line up with the threaed holes in the side of the airframe any longer. Apparently, over the years the rear arn has been bent downward. One of the first things I noticed, the first time I removed the rear seat, was that a new hole had been drilled in the lower bar to accomodate a more aft location of the forward bolt. I am not sure just how to fix this problem. I have considered trying to rebend the rear attachment bar, but hesitate to do so for fear of breaking it off altogether.

Robert, I am having a difficult time visualizing what you are describing. Could you reference the IPC by Fig. and Item numbers so I can undertand your description?

[Robert Eilers]

George,

The best description I can find is located on page 53, figure 31 - rear seat. Item 31-1 reflects the AN bolt for the rear support bar - my is bent slightly upwards. Item 31-2 reflects the lower support bar, under the seat, it is possible to see the bolt hole in the support bar that runs under the seat. The previous owner apparently drilled a second bolt hole approximately 1/2 inche back from the original to accomodate the more flat profile of the seat. Item 31-3 reflects the brackets that my seat no longer lines up with. The bolt holes on the sides of my seat are to low to line up with the side bracket bolts holes.

[GAHorn]

Robert, none of that makes sense to me. (sorry)
Fig. 31 (of the Cessna 170 B model is of the rear seat. (none of the other IPC's, either the 170 or the 170A is of the rear seat..... I certainly hope we're both talking about the same airplane model...)

IN any case, Fig 31 , of the 170 B model, (at least in the IPC which I have) which does address the rear seat, does not correspond with what you are describing.

In MY IPC, Fig 31, item 1 and item 2 shows the lower seat attach bolts. But item 31-1 is not the rear support...it is the FORWARD support. Item 2 is (not the "lower" support)...but is the REAR support.

These are bolts which attach the seat to the FLOOR.

Two additional bolts attach the seat to the sides (brackets) of the aircraft. Are you certain you are looking at a Cessna 170B parts catalog and you have a 170B seat?

[Robert Eilers]

Thansk anyway George - I'll sort it out.