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Esser
10-24-2017, 10:56 AM
Looking at the manual, it doesn't really outline which carry throughs to use for what. Does anyone have any tips? Or pretty much just use what is closest/ most convienient?

How is everyone sealing up their carry throughs?

Dave S
10-24-2017, 01:33 PM
Josh,

Right or wrong...I pretty much used the ones closest to each bundle.

Ideally, a person could use metallic firewall penetration fittings but they are sooooooo expensive. I conferred with the DAR who was to inspect my plane; and, he suggested using the red RTV fire sleeve goo generously over the supplied rubber grommets. A person would not win "artist of the day" with he RTV; but, it is supposed to protect the rubber for a period of time in the event of an under cowl fire.

One photo attached showing some of the spots I used the red goop.....remember - no awards for artistry for me now!:rolleyes:

Given that we have fiberglass both in front and behind the firewall, I don't think it is possible to fireproof the cabin from under cowl flames to perfection, but we can probably extend the safe time a bit to get it back on the ground. Personally, I think doing things so that a fire would not likely start under the cowl is our best line of defense.

ken nougaret
10-24-2017, 02:44 PM
Where did that shirt come from? Just slightly off subject.

Dave S
10-24-2017, 03:38 PM
Off topic response:

Ken,

Came from a custom t-shirt shop at the local mall.....here's a photo of the back....the one on the left is mine, the one on the right is my wife's. The front is the same on both; and, the running fox was one of the shops file images.:)

jiott
10-24-2017, 04:54 PM
Josh, I pretty much did similar to Dave, used the most convenient pre-punched holes and drilled a new one or two. Used short pieces of firesleeve thru the rubber grommets, but did not use the RTV goo although I think it is a good idea and may do it myself.

jrevens
10-24-2017, 07:07 PM
Josh,

I used some formed S.S. flanges that I had in my "spare airplane parts inventory", along with fire-sleeve & hose clamps. This is how many builders of other types do it. There are other ways to do it of course, and I think the grommets along with red silicone sealant is fine. You can see one in the first photo (BTW, the heater fittings in that picture are not the ones I ended up using). I ran all of the battery related wiring, as well as solenoid relay, charging system wiring, landing light wiring and oil pressure through the one on the right side of the firewall. Ran most of the other sensor wiring, tach signal, ignition, etc. through the left one.

Dave - I love your t-shirts!

Esser
10-24-2017, 07:28 PM
Thanks for the pics and replies everyone. It is always appreciated. I think with the TCU sensor wiring and the EFI harness, I may need a bigger/more carry through spots. I didn’t even think of cabin heat until you mentioned it John.

jiott
10-24-2017, 09:51 PM
A shot of my wiring thru the firewall.

Dusty
10-24-2017, 11:14 PM
Very tidy Jim,be careful with your carb vent as these are very sensitive to pressure variation.The tape under the zippies is a nice touch:cool:

N981MS
10-25-2017, 05:10 AM
I do not have a photo handy but on the Zenith we used the fire sleeve. For the grommet we went to the Home Depot aviation electrical department and got the grommets used for electrical box knockouts. They come in various sizes and seemed to work well.

jiott
10-25-2017, 09:37 AM
Dusty, the photo shows my carb vent line just hanging free, but actually I run it into a tight fitting hole in the back of each air filter. Has worked fine for over 500 hours.

Cherrybark
10-25-2017, 04:46 PM
Always in favor of thread drift, the "Enabler" cracked me up! Your wife has to have a great sense of humor!