Compass Fluid?

How to keep the Cessna 170 flying and airworthy.

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Lee
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Compass Fluid?

Post by Lee »

I have a very slight leak (one drop every 5-10 min) when flying above 6,500' in an Airpath compass. Anyone ever used the repair kit sold by Aircraft Spruce? What is compass fluid? It is listed as hax mat with a haz mat charge. I wondered if I could buy the fluid locally (Memphis). Thanks, R/Lee
beeliner
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Post by beeliner »

Gosh that sounds high tech and expensive. I thought it used to be kerosense;-) Some had alcohol. I think a silicone fluid had been common for quite a while. Better let George tell us for sure.
jims170
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Re: Compass Fluid?

Post by jims170 »

Lee wrote:I have a very slight leak (one drop every 5-10 min) when flying above 6,500' in an Airpath compass. Anyone ever used the repair kit sold by Aircraft Spruce? What is compass fluid? It is listed as hax mat with a haz mat charge. I wondered if I could buy the fluid locally (Memphis). Thanks, R/Lee
Well...I would take a quart glass jar to the local FBO and ask for a little solvent out of the 55 Gal drum. The jar opening should be big enough to fit the compass in to submerge it.

BTW, you do realize this is not an approved repair in the eyes of the FAA.
Jim
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Lee
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UhOh!

Post by Lee »

A) I did not realize/*forgot that this would not constitute an approved
repair ... good point.
B) The airplane is such, and my career at FedEx is such that I do not want
to jeopardize either ... having said that ...
B) One would then surmize that there are but two solutions. :->
1. Take the compass to an instrument repair shop (ouch)
2. Buy a new compass and have the installation appropriately signed
off ... oh, well! :->
Thanks guys ... I do want to keep things legal. This is but one reason why I like this organization! R/Lee

* Long week ... my mother passed away rather suddenly here in Memphis on the 23rd; we held the funeral in Palatka, FL on the 27th ... got back to Memphis yesterday.
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Bruce Fenstermacher
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Post by Bruce Fenstermacher »

Lee

My condolences on the lose of your mother.

The repair kits are pretty straight forward. They are just new gaskets basically. I've heard all sorts of things being used for fluid but I wouldn't use any thing other than the right stuff unless someone could give me better proof of what can be used.

While I know this isn't legal I know many mechanics that replace the gaskets and fluid. Or at least they have the fluid in stock for some reason.

Not a month ago while admiring the simplicity of my Cub panel a local FAA safety inspector noticed the mag compass only 3/4 full of fluid. He turned to my IA and said "you really should give your friend some compass fluid some time" then smiled.

I certainly understand your position as I fly for a living as well.

Now lets see if your plane goes into the hanger with a good compass and the doors are closed. Then when the doors open and the plane emerges with, surprise, good compass. Did anything happen in the hanger?

Oh this was a buddies plane you talking about that may need fluid.:wink:
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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Lee
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Wink Wink! :->

Post by Lee »

Let's see ... new T hangar ... and what really goes on behind closed hangar doors? TNX R/Lee

PS And the compass really does work very well ... got me home from Winterhaven!
Tom Downey
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Post by Tom Downey »

clear lamp oil..from your local hardware store.
Tom Downey A&P-IA
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3958v
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Post by 3958v »

I used the compass repair kit and it worked fine and it included a new gasket. I would go that route again as the compass is good as new. I don't remember any Hazmat problems. Bill K
Polished 48 170 Cat 22 JD 620 & Pug
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blueldr
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Post by blueldr »

Compass fliud in the military used to be "water free" kerosene. I don't fly anymore where it is that cold, so I just use paint thinner (mineral spirits) or regular kerosene when I reseal a wet compass. I believe any A&P is authorized to install a reseal kit and refill an Airpath type compass.
BL
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Lee
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Good deal ... TNX!

Post by Lee »

Good information ... I appreciate it! I do happen to have another Airpath compass I can "experiment" with and a friendly, local IA I can enlist! ;-> R/Lee
Tom Downey
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Re: Good deal ... TNX!

Post by Tom Downey »

Lee wrote:Good information ... I appreciate it! I do happen to have another Airpath compass I can "experiment" with and a friendly, local IA I can enlist! ;-> R/Lee
You bes just do it and say nothing.

There are too many folks who believe this is a instrument repair shop repair.

Remember a compass is a required primary instrument, no matter how simple it is.

Letter of the FAR = instrument repair shop.

Good ol boy = easy do.
Tom Downey A&P-IA
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Lee
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OK

Post by Lee »

I think I am having a "selective senior moment" (which I qualified for on the 3rd of this month! :D
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GAHorn
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Post by GAHorn »

Lots of compasses have been repaired with the repair kit that is sold via Spruce, Univair, Chief, WagAero, and others. I've done it and it works just fine, if the directions are followed. (Hardest thing is just making certain the compass is completely submerged to get rid of all the bubbles.)
This used to be a common repair performed by mechanics in the course of regular maintenance. The FAA got involved when some CRS (Certified Repair Stations) were found to be doing it without proper instrument certification or repair/overhaul manuals. The reaction has generally been downright silly over it, in my opinion. In most cases it's a simple gasket and fluid replacement that involves no other modification/repair of the unit. If care is used, no danger to the mechanism/operation exists. (And since that's the case, then why do the FAA condem this simple repair ... but allow any mechanic, even an owner, to adjust/calibrate his compass at the airport compass rose?)
Kerosene has been used for many years, but it will eventually "yellow" the compass numerals. Compass fluid is a clear safety-solvent, and I'm surprised they're claiming it's hazmat.... it's safety due to flashpoint is one of it's features. 8O

This situation reminds of the the local game warden, whom I'd queried regarding whether or not it was legal to hunt a turkey on my own ranch for the table, without a permit/license, similar to certain laws regarding fishing on private ponds. His response was, "If you can't kill a turkey on your own 1500 acres and get away with it..... then you deserve to get caught!" :lol:
'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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Lee
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Que Pasa? (ie: "compass, what compass"? :-> )

Post by Lee »

Thanks for the information George ... "what goes on behind closed hangar doors"! :wink: Regards, Lee
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GAHorn
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Post by GAHorn »

I visited with a local FAA Inspector here in DFW region about this today. He felt it to be a simple matter any A&P who felt qualified should be able to service the fluid in a compass. (He also said he understood the position of some inspectors and some repair stations who felt it was inappropriate for a CRS to service equipment for which their certificate did not apply due to lack of manuals and specifications.)
He also stated what we all know to be true....different inspectors may see this issue differently, and that the local FSDO chief mx inspector should be consulted if you intend for a local mechanic to do this work. (Otherwise, I suppose you might want to ship it to another region, have it repaired, then returned.) :roll:
Do what your due-diligence indicates, but keep in mind it's the Owner who is responsible for the airworthiness of the airplane, regardless of what anyone says.

BTW....I really had to resist giving you a different answer on what the compass fluid consists of: Single-Malt Scotch Whiskey. (How else do you think they got the moniker? Besides, it becomes a good survival tool after you remove it and get lost in the snow!) :lol:
'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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