S

Steve

Well Known Member
I toured the Cessna factory in Independence, KS last weekend. Just a few notes from the 172-182-206 production lines:

1. They bolt the engine mount to the finished engine then attach the assembly to the firewall.

2. They make their own wiring harnesses one wire at a time using pattern boards but they use white plastic tie wraps, not string for bundling.

3. You can have any color seats and interior as long as it is tan with a painted gray instrument panel.

4. They only build glass cockpit (G-1000) planes. Even the lowly 172.


Steve
 
Steve said:
I toured the Cessna factory in Independence, KS last weekend. Just a few notes from the 172-182-206 production lines:

1. They bolt the engine mount to the finished engine then attach the assembly to the firewall.

<snip>
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That's how I would do it too, IF I had the engine on hand and ready to install. Unfortunately for me, like many, I don't have an engine sitting around when it's time to install the engine mount to the FW.

I DO think this is the easiest way to fit the mounts and bolts...

I'd LOVE to take a tour of ANY airplane manufacture plant!:cool:
 
maybe but

i think it is easier to have the mount on the plane first as you need to compress the bushings on dyna 1-2 mounts to get the bolts to go in. the conical no prob. with the mount on the firewall you have a little help by the weight of the eng/plane. once you try it, if you havent already, you'll see what i mean.
 
Hey, you weren't that far from me, I take a tour of the place about once a semester. You didn't happen to go through Pittsburg did you?
 
no Pittsburg

We arrived in Tulsa via United Friday night and drove to Independence arriving about 2300. Saturday morning found us at the Customer Delivery Center checking out the new CAP 182 we were to deliver back to Utah. Flew the plane, took pictures, took the tour, went to lunch. Decided to wait out the wx until Sunday AM. Smooth ride but it took 9.0 hours to get home with 50-60 kt headwinds. Nicely equipped plane with G-1000 (AP and XM music and wx).

Steve
 
I grew up in Neodesha, about 20 miles to the north of the Independence airport. Went to KU for my engineering degree. I rememer flying to Independence as a student once. Landed and came back home as there was hardly anything there (but still more than at good old 2K7). Rock Chalk Jayhawk!
 
Attaching the mount to the engine prior to attaching the mount to the fuse may allow for more a accurate torque of the bolts between the mount and the engine as you don't have any appreciable weight to affect that torque.
 
it will for 1 bolt

WildBill said:
Attaching the mount to the engine prior to attaching the mount to the fuse may allow for more a accurate torque of the bolts between the mount and the engine as you don't have any appreciable weight to affect that torque.
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but when more than 1 bolt is in, there is preload on the bolts. i torqued the nuts not the bolts. either way will work. one is easier. either mine or yours, i have not installed one "mount off the plane." just put in your fittings before installing the mount either way.
 
While the mount is installed on the fuse, the difficulty in zeroing the loads of gravity or excess jacking pressure will affect the accuracy of the torque on the engine-to-mount bols/nuts.

If the mount is not on the fuse, those loads are negligable.

Doing it that way can take the mount torque variable out of an engine-sag issue.
 
Steve said:
They bolt the engine mount to the finished engine then attach the assembly to the firewall.
Click to expand...

I just mounted my engine on the motor mount last Friday...took 2.5 hours because lining up the bottom holes was a bear! I had 2 friends here helping, and I believe all 3 of us at one point or another commented that it'd be easier to put the mount on the engine first, then attach it to the firewall.

Now that the engine is hung, I hope I don't need to remove it!
 
but did you

lostpilot28 said:
I believe all 3 of us at one point or another commented that it'd be easier to put the mount on the engine first, then attach it to the firewall.
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has any body done both ???
which way would be easiest i did mine alone, took around 30 minutes fiddling with it.not including the starring at it that probally took an additional hour or so. would'nt take that long now.
 
Builder tip

A local RV-6 builder mounted his mount to the engine first (Cessna method). He said it was much easier to jockeyr a 5 pound mount than a 275 pound engine.

I did mine Van's way and had to:
1. remove the mount to squeeze the rivets fastening the bottom row of cowl hinge rivets. Fortunately the engine wasn't on yet.
2. invent a thin squeezer die/bucking bar for the firewall rivets next to the top mounts. Dan C also.

TIP:
mount ALL the bottom cowl attach hinges before installing the engine mount

Steve
 
I have found that the only way to mount the engine is to make sure it is at the right height and lined up perfectly. Get the tail up in the air and the longerons level in all planes. If you do this, then one person can easily mount the engine with no difficulty. If you don't do it this way you are in for a lot of cussing, with all the members helping you mount the darn thing. It took me a few tries and few planes later to figure out.
 
Not a factor

WildBill said:
While the mount is installed on the fuse, the difficulty in zeroing the loads of gravity or excess jacking pressure will affect the accuracy of the torque on the engine-to-mount bols/nuts.

If the mount is not on the fuse, those loads are negligable.

Doing it that way can take the mount torque variable out of an engine-sag issue.
Click to expand...

With AN7 Bolts, the Weight of the engine is not a factor while torquing, but the positioning is a factor in getting the nuts started properly before torquing.

I bet most do not know that an high quality 6-32 alloy steel socket head cap screw will take over 1,000 lbs of direct tension before failing.

But I would not let it hold my engine on, I want at least a 20x safety factor.

P.S. The suggestion of having the engine floating is still a good idea, its just easier.
 
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> With AN7 Bolts, the Weight of the engine is not a factor while torquing, but the positioning is a factor in getting the nuts started properly before torquing.


Unless you have the engine perfectly suspended, there is no way it will not affect the torque, no matter what size bolt it is.

ie. you are tightening a nut against a load vector of either: the weight of the engine, or excess jacking pressure.
 
Norman CYYJ said:
I have found that the only way to mount the engine is to make sure it is at the right height and lined up perfectly........ If you don't do it this way you are in for a lot of cussing, with all the members helping you mount the darn thing. It took me a few tries and few planes later to figure out.
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Truer words were never spoken! I have participated in a few "engine hanging parties" and my experience is they are more trouble than they are worth, except for the beverage portion of the party. :)

Working alone, the engine I hung on the 6A went on so fast I somehow felt "gyped" and then just for grins unbolted it, set it back down on the pallet and reloaded it again. I mean after all, how often do you get to hang an engine? The IO-360 in the latest project is the third engine I have hung by myself. I started to have trouble this time because I fussed with leveling the airplane. Hard to believe but the engine mated to its mount perfectly when I simply let the (taildragger) airplane sit normally and the engine was dangling from the hoist naturally. As you can see, the angle was pretty close. The whole key to hanging an engine by yourself is not working at cross purposes and then work to make sure the engine's mass and weight work for and not against you.

 
Good on you Rick. You have found the answer also. My engines that I have hung have always been hanging level from the hoist. I guess the lifting hook was on a different bolt then yours. But the secret is to have everything square to each other. I can't imagine wanting to take the engine off because it went on so easily. I would be sitting down to a cool one and feeling pretty good not tempting fate. What's the rest of the story Rick why did you really take it off again only to reinstall it.(what did you forget to do....lol)
 
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