Red and Brown; what is this stuff?

[stormman]

Re: Red and Brown; what is this stuff?

I need a Taylorcraft whisperer

Hello Jack
i hope we get this settled soonas your probmelo is bugging me too.
imstill checking my resources but getting blanks.
29 years here too and i love Salsa but i just Can't dance.
I understand Forrest and Bob both whisper, don't let them tell you otherwise and Robert Lee has those stains all over England , not just on the planes though

[hangarb7]

Re: Red and Brown; what is this stuff?

Update:

This carb DID have some 80 octane run thru it. I further discussed it with the previous owner and it turns out that he does remember that it had some 80 in it right after it was rebuilt. He said the carb was really red stained and leaky before he had it rebuilt by a rebuilding service out West.

He thinks it might just be that the carb is leaking a little and it's drawing the residue out.

But I have another question. This is a BC12D with original C65, and of course, no mixture control. How do you folks shut yours down? I always idle down the narrow taxi way between the hangars at FWQ and turn off the switch when I'm within coasting distance of my hangar. Then I close the fuel tank valve.

Should I be shutting the valve first and letting the fuel be consumed by the engine before turning the key off? I know that if I accidentally leave my fuel valve on, the carb with eventually drip.

What's the proper procedure?

Tonight, I'll go to the hangar and see if I can look inside the wing tank to determine the brown dust issue.

Thanks all,

Jack D.
N44057

[Richard Boyer]

Re: Red and Brown; what is this stuff?

I just turn the mags off. That is the best mag test ever too....... Of course I run it quite often so I don't worry about the fuel going bad.

Lately I have only been filling up the main tank so I probably need to put a couple of gallons of Avgas in the wing tanks so the residual autogas gets flushed out.

[M Towsley]

Re: Red and Brown; what is this stuff?

Jack,

The 'official' way is to idle at 800rpm, shut off the mags and at the same time briskly open the throttle all the way. Off course, remember to return it to idle when done. Supposedly prevents the possibility of backfire, as well as removes residual fuel from the passages. I also shut the fuel off while a couple hangars away to consume most of what is in the bowl. Has worked for me, though most will just shut off the mags at idle without problems.

[crispy critter]

Re: Red and Brown; what is this stuff?

I am an autofuel believer but at the same time you really don't want to leave auto gas in the carb for very long. Small quanities of auto gas goes bad much faster then a 12 gallon tank full. So what I do is shut the gas off and let it run out everytime I plan on shutting her down for the night. I know a lot of people will say that takes too long but i have it timed so that at my home base i turn the gas off as soon as exit the runway onto the taxiway and run 1400rpms all the way to the hanger amd then it takes about 10-20 seconds to quit once I reach the hanger. I also do a mag shut off check during ever run up. Everone says you don't have to worry about av gas going bad and that is true for the most part but if you have a mag go bad or a P lead come loose and someone turns the prop it can't run if there is no gas....it may fire once but it will not run.I just feel much safer at night knowing the carb is empty.

[1938BF50]

Re: Red and Brown; what is this stuff?

FWIW, At 900/1000 rpm's my A-65 runs 40-45 seconds after fuel shutoff (several checks). I too leave the carb empty for safety (too many kids around).

[Richard Boyer]

Re: Red and Brown; what is this stuff?

I went flying this evening and did the 800rpm, turn off mags and push in full throttle when I was done.

It stopped just the same.... I do like the idea of burning the fuel out of the carb.....

Anyways, I was sitting there with the throttle full in when it dawned on me that I really didn't have the brakes set. If the mag shutoff had failed, I probably would have gone straight into the wall in the back of my hangar. I do believe that would have sucked......

Get out of routine, do something possibly stupid......

[hangarb7]

Re: Red and Brown; what is this stuff?

I also went flying in N44057 last evening. Last Saturday I didn't fly but I wiped the bottom of the cowl to remove the red stain.

When I got to the hangar last evening, there was no additional red stain. I did some maintenance then went flying before sunset (beautiful!).

I pulled the fuel knob on the main ramp and taxied to my hangar. That took one minute. From there to empty carb took one more minute.

We'll see if there is any further stain on the bottom of the cowl after she sits for a few days.

I did not then have chance to check inside the wing tanks for the brown dust and the fuel screen's condition. I'll report on that on Saturday.

Thanks all,

Jack

[Sloanlow]

Re: Red and Brown; what is this stuff?

Tribe

I had a tri-pacer that I fueled with auto gas. Many times I over fueled the wing tanks. That caused that red dye to drip out of my wings. I think this is simular to what you are experiencing. It is funny that it just keeps getting washed out. I think that your leaky carb is washing it out of your aircleaner and cowl.

Check to see if this airplane was once based where it could be fueled by the old 80 oct red (if they still have it any where).

Sloanlow

[hangarb7]

Re: Red and Brown; what is this stuff?

Sloanlow,

The carb was professionally rebuilt in the early '90s. It then had some 80 octane thru it then but none since. The original owner told me that before rebuilding the carb was leaky and very red-stained.

But you raise a very interesting possibility. The inside of the cowl is perfectly clean aluminum (I do not think it is the original cowl). However, the stain keeps forming around the rivetted edge of that aircleaner bump just below the carb. Since the stuff wipes off easily, or at least easily wipes off with 100LL on a rag, it could be that there is a residue somewhere in that cowl, maybe between some rivetted metal and it is being rejuvenated when my carb leaks a little. I think you have something there...

Thanks for the thought.

Jack D.

[M Towsley]

Re: Red and Brown; what is this stuff?

Jack,

You may be on to it. I used the Magna check red dye stuff to check my motor mount. It got underneath into the areas around the reinforcements. I was never able to completely get this stuff out of there even though I soaked these spots in solvent. Every time I went to prime it or paint it, it would bleed out. My wife, who is in the Motor Fuel Section of state government was told the red dye used in dyed diesel, (for off-road use), is similar. She was told if you place one drop on your desk and you left for lunch, it would contaminate the complete desktop by the time you got back. If your carb had dripped while using the 80 octane then the dyes might have migrated and stayed in between the metal of your cowl.