Cotton Waiex 191 - N191YX

[Bryan Cotton]

Thanks Robbie! I do have some left, it may make it. If not I'll take you up on your offer.
Merry Christmas all!

[Bryan Cotton]

Here are my seat cushions. I still have a little trimming to do. I did my first real sewing with the machine today. Fixed two belt loops on my pants.

[Bryan Cotton]

Today I checked two things off my punch list. Polish tailcone bottom skin, and mixer access panel nutplates.

[Bryan Cotton]

I am working my oil filter. Unfortunately I had to go to a slightly smaller filter because of where I mounted the remote filter fitting to the firewall. That was a screwup. I've decided to do hard lines to the back of the engine and then flex lines from there. Here is my oil line bracket to accomplish this.

I used CNC to make this (Cotton Nifty Construction or Cotton Not CNC).

[Bryan Cotton]

Adam made the first hard line for the oil filter plumbing. Do you guys use firesleeve on hard lines?

[lstinthot]

Adam made the first hard line for the oil filter plumbing. Do you guys use firesleeve on hard lines?

first hard oil line.jpg

I do not know the answer to your question but do have a comment on oil lines. We had recurring oil leaks on our oil lines on large pumps at work. The lines were hard piped and we kept fixing one leak just for another one to start. We switched to a stainless braided oil line and have not had any leaks in years. I plan on using braided lines once I get to that point.

[racaldwell]

For a data point, the hard line on my Lycoming for prop control is SS tube with steel flare fittings. It does not have fire sleeve. The melting temp for SS is more than double for AL. I have not had any leaks after 1000 hrs of use.

Rick Caldwell
Xenos 0057

[Gordon]

Firesleeve Fuel Lines

There is no reason to firesleeve oil lines......but I would NOT use any hard lines on the engine, whether oil or fuel.....especially coming from the firewall (stationary) to the engine (vibrating). They will "work hardened" after a while and are subject to cracking.

Yes, I also had a hard line (stainless steel) from my prop governor to the front of the engine on my Lycoming and of course it is not firesleeved because it is an oil line......it had a couple of "standoffs" to control the vibration.


ALL fuel lines should absolutely be firesleeved FORWARD of the firewall. Aft of the firewall.....not needed. Don't use Home Depot water pipe insulation. Buy the good stuff from Aircraft Spruce.

I like to buy all my fuel lines from www.tsflightlines.com They are braided Aeroquip lines and they will come already firesleeved for in the engine compartment (at your request). Tom Sweargin sells a LOT of braided lines to the Van's guys......and he has better prices than ACS.

Also note: your fuel fittings on the engine and that line going to the gascolator (or firewall bhd fitting) should be steel........the aluminum fittings tend to "work harden" after a while, crack and a fuel leak in the engine compartment can be fatal (fire). Don't forget to attach a "heat shield" to the exhaust if the fuel line gets too close to the exhaust pipe.

I have flew my Hummel Onex in 90 F degree weather and NEVER had any "burping" (vapour lock) problems on long taxi runs.

Gordon.....Hummel 2400...Onex......(RV repeat offender)

[Gordon]

Firesleeve Fuel Lines......Typo...Correction

I made a "typo" in my response to fuel lines.

The way it reads.......

It sounds like I am saying the "fuel line" from the engine to the gascolator (or firewall bhd fitting) should be steel........

NO....that line should be a braided flex line (firesleeved) ...... the FITTINGS it attaches to at the engine and the gascolator should be STEEL.

Sorry for the confusion.......

Gordon.....Hummel 2400...Onex

[DCASonex]

Thanks for the info on fuel lines and about aluminum fittings. Had planned to replace some lines in mine this summer and will check out your source.

David A.