Is it Brake fluid?

SixPapaCharlie

SixPapaCharlie

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Just got the plane out of annual. We had them do a brake job. It wasn't due but it was close.

Tonight I went out to put a new gas cap on our left wing (someone decided they wanted it more than us. I guess we need to lock them)

I notice pax side, coming from one of the cowl screws a stream of what appears to be oil but on closer look is sort of yellow/ orange.

Pull off the cowl, and what reminds me of some sort of master cylinder on the top of the firewall near the battery has a small pool of this fluid on it.
I am guessing this is the brake cylinder but I am used to brake fluid being red even in the other plane it was red.

I hop in the plane and stomp the breaks a few times to see if any more discharges but nothing.

I figure at some point it has to be coming out under pressure to get up near the cowl screws. We rarely fly the plane inverted so it is not dripping up there.

Thoughts?


Also Cost of a gas cap $309 because why not.
 
The red pigment fades. You tell what it is by feel, smell, and taste.
 
This thing circled in yellow

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It'll be 5606. When they bled the brakes they pump the fluid up from the caliper and they overflowed the reservoir. CRC Electromotive or Brake Clean in the red can are what I use on messes like that.
 
When they did the brake job they pushed the pistons back in the calipers to make room for the new pads. Fluid then got pushed back up to the reservoir and overflowed a bit.

Not a problem, just wipe it up.
 
Silvaire said:
When they did the brake job they pushed the pistons back in the calipers to make room for the new pads. Fluid then got pushed back up to the reservoir and overflowed a bit.

Not a problem, just wipe it up.
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Doh, yeah, read that wrong, either way same thing, no worries.
 
Thats a lot of stuff packed under that cowl. Very clean.

Clean up the hydraulic fluid and if it doesn't reappear don't worry about it.
 
SixPapaCharlie said:
This thing circled in yellow

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Yep, brake fluid resovour. It should only be about 1/2 full to allow for expansion. It would be a good idea to drain some out so it doesn't leak again after it warms up. Take the breather cap off. Use a straw and dip it all the way in, put your thumb on the end of the straw to hold the fluid in. Repeat till the resovour is 1/2 -3/4 full. Check the level during every oil change.

Mil-H-5606 is the type of hydraulic brake fluid used in airplanes and other equipment. It's a military specification. ;)
 
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Bryan,

I made it a habit of pulling the top cowling monthly for a visual check.

Next time you do, it would be a good idea to have someone, a mechanic or experienced Cirrus owner, help you identify all the components and what they do, along with know weak points (alt air bracket, for instance).

Also a good time to wipe things down with Corrosion-X or Pledge or whatever is appropriate for the item. I used Corrosion-X on baffles, firewall and anything aluminum, and Pledge on anything painted, plastic or rubber. A clean engine is a happy engine.

Finally, on re-cowling do not forget the little pan screws that hold the cowling together near the prop. And never run the engine with just the top cowl off. There was a recent thread on COPA showing the possible results, and they ain't pretty!
 
Clean it up really well. Brake fluid is very corrosive. On hydraulic brakes when new the master cylinder will be full. As the pads wear the fluid will drop to compensate for the pad wear.

People will check this fluid and say, oh I need to add fluid. Yes the fluid is low but you do not need to add fluid, you need to replace your pads. Once the pads are replaced the fluid will once again be at the top or full.

If you do add fluid, on the next pad replacement or brake service the master cylinder will over flow if fluid is not removed. 99 percent of mechanics do not remove this fluid they just let it over flow. They are on the floor doing this work. They get up to check the master cylinder to find its over flowing. I have seen this a lot. They then shut the hood saying, that fluid will hurt nothing.

Yea right.

Tony
 
FastEddieB said:
I was under the impression that one big advantage to 5606 is that it is NOT corrosive.

Am I wrong on that?
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I would say your not wrong on that. That info was just kinda generic info from the auto world. I would still clean it up really well. But I bet your right. That would be a good test to do. Put a few different materials in some of this stuff and let it set for maybe a few months and see what it does to it.

If you have some rusty nuts and bolts you want cleaned like new. Stick them in some DOT brake fluid for a couple weeks and they will come out like new.

Strips paint really well to.

Tony
 
FastEddieB said:
I was under the impression that one big advantage to 5606 is that it is NOT corrosive.

Am I wrong on that?
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5606 is 10 wt mineral oil so it is non-corrosive and flammable. Essentially it is hydraulic oil and similar to what is used in tractor hydraulic systems.

5606 is not automotive brake fluid.
 
I think it's honey because your airplane is so sweet. Just ignore it (or put it on your toast) and keep flying. ;)
 
SixPapaCharlie said:
Just got the plane out of annual. We had them do a brake job. It wasn't due but it was close.

Tonight I went out to put a new gas cap on our left wing (someone decided they wanted it more than us. I guess we need to lock them)

Also Cost of a gas cap $309 because why not.
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Check eBay for someone selling your gas cap in the DFW area...
 
Kiddo's Driver said:
Check eBay for someone selling your gas cap in the DFW area...
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That was strange. I was going to go around the hanger and see which gas cap our key fit into and just lock it on that plane. There are cameras everywhere so better to not do that.

Edit: and it very well may have not been stolen. I landed, they came out to fuel the plane, I said "not needed", please put the plane away. The next morning the cap was missing.

The FBO actually reimbursed the price of the cap since they said it was possible one of their guys may have misplaced it during that exchange which was really nice.
 
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SixPapaCharlie said:
That was strange. I was going to go around the hanger and see which gas cap our key fit into and just lock it on that plane. There are cameras everywhere so better to not do that.

Edit: and it very well may have not been stolen. I landed, they came out to fuel the plane, I said "not needed", please put the plane away. The next morning the cap was missing.

The FBO actually reimbursed the price of the cap since they said it was possible one of their guys may have misplaced it during that exchange which was really nice.
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Weird story......:confused:
 
N801BH said:
Weird story......:confused:
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Maybe, maybe not. About 5 years ago when I was flying club planes, I filled up the old 182 at a full-service FBO at a neighboring field. I spot-checked the caps, meaning I verified that the cap on one side was tight, but not the other, and I did not make a note of which side I checked. From there I flew to a $100 hamburger spot and then back to home base, a total of about 50 minutes in the air after fueling. In the morning, one of the gas caps was found missing by another club member. The kicker was that the tank was not abnormally low given the amount of flying since the fuel stop. So although I was in the wrong, and took the rap for not checking both caps after fueling, I always suspected that someone might have "borrowed" the cap. The club has 40 members, several of whom own 182s, and club stuff disappears all the time anyway.
 
azure said:
Maybe, maybe not. About 5 years ago when I was flying club planes, I filled up the old 182 at a full-service FBO at a neighboring field. I spot-checked the caps, meaning I verified that the cap on one side was tight, but not the other, and I did not make a note of which side I checked. From there I flew to a $100 hamburger spot and then back to home base, a total of about 50 minutes in the air after fueling. In the morning, one of the gas caps was found missing by another club member. The kicker was that the tank was not abnormally low given the amount of flying since the fuel stop. So although I was in the wrong, and took the rap for not checking both caps after fueling, I always suspected that someone might have "borrowed" the cap. The club has 40 members, several of whom own 182s, and club stuff disappears all the time anyway.
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I would switch clubs....

I HATE thieves.......
 
A properly designed fuel cap system has a SS security chain and T bar in the tank so the cap can't leave the plane(without serious finagling). :wink2:
 
docmirror said:
A properly designed fuel cap system has a SS security chain and T bar in the tank so the cap can't leave the plane(without serious finagling). :wink2:
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That, and.....

Just another reason NO ONE fuels or touches my plane.....
 
N801BH said:
That, and.....

Just another reason NO ONE fuels or touches my plane.....
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Even when you tell them no it still happens. Although my wording could have been better, when asked if I wanted it topped off I was polite and said: "Not right now", which in hindsight was ambiguous and I've altered my phraseology to include; "please don't touch any part of the plane while it's here without contacting me first." Even said politely, it's still rude, but it works.
 
1600vw said:
I would say your not wrong on that. That info was just kinda generic info from the auto world. I would still clean it up really well. But I bet your right. That would be a good test to do. Put a few different materials in some of this stuff and let it set for maybe a few months and see what it does to it.

If you have some rusty nuts and bolts you want cleaned like new. Stick them in some DOT brake fluid for a couple weeks and they will come out like new.

Strips paint really well to.

Tony
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DOT3 brake fluid isn't used in airplanes. DOT3 is alcohol-based and can be nasty stuff. The MIL-5606 we use in light airplanes is just a thin oil.

The Skydrol fluids used in some heavy aircraft is nasty and will eat some stuff. Never worked with it, not even on the Electra.

I worked 12 years as a shop foreman in a brake remanufacturing machine shop. That outfit made lots of money rebuilding hydraulic brake components into which operators had put the wrong fluids. The wrong stuff dissolves or swells the rubber seals.

Dan
 
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docmirror said:
A properly designed fuel cap system has a SS security chain and T bar in the tank so the cap can't leave the plane(without serious finagling). :wink2:
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Do you consider a snip with a set of pliers serious finagling?:dunno::lol:

If someone wants to steal something, they are going to steal it. Typically securing it just increases the collateral costs, like fishing out that non magnetic cross bar from your tank.;)
 
docmirror said:
A properly designed fuel cap system has a SS security chain and T bar in the tank so the cap can't leave the plane(without serious finagling). :wink2:
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Well then there are a heck of a lot of improperly designed fuel cap systems out there ;) The potential downside is the damage an unsecured but tethered fuel cap could do to the wing as you go around the pattern to land and find out what the heck that banging noise is.

My missing fuel cap story is similar to the others. I decided to get fuel at PCV and they had full service, which is not very common these days. So the kid came out and set up the ladder but they still had the regular kiosk and it wouldn't read my card because it was cracked. They couldn't take cash or manually start the pumps without the card and I had enough fuel to get home so I told the kid to forget it and I guess he took that literally because he forgot to put the cap back on.

Of course the onus was ultimately on me because I never checked before jumping in and taking off. I just wasn't accustomed to full service or having anyone else touch my airplane during fueling but lesson learned.
 
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Silvaire said:
Well then there are a heck of a lot of improperly designed fuel cap systems out there ;) The potential downside is the damage an unsecured but tethered fuel cap could do to the wing as you go around the pattern to land and find out what the heck that banging noise is.
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Never seen that, and I've been around a lot of Bonanzas over the years. Surely it's happened before, but the damage will be cosmetic, and a good use case for body filler. Suspecting that the fuel filler is in a location forward of the spar that it would be a fairly high pressure area, and not much banging around, but I'm not going to go test it. :eek:
 
I've departed with a cap tethered and loose. The only way I knew something was wrong was that I took off with half tanks and once I leveled off and looked my gauge registered full. It took a moment to figure out what was happening but then I turned around and landed. I found that tank mostly empty although the air pressure over the filler had lifted the sender to show full. There wasn't as much as a scratch on the wing.

And by the way, I've dribbled 5606 on urethane paint, dope, tires, etc and have never had a problem. I had a brake master leak into the belly of a Cub and saturate the unpainted side of the fabric. I wiped up the excess and there was never a problem after that with the fabric coatings.

On the stupid side, I used it to fill a brake system on a snowmachines one time. I have 5606 laying around. I haven't bought automotive brake in 20 years. It seemed like a good idea at the time. The result of using it cost me a new brake system on what was a new sled.
 
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Stewartb said:
I've departed with a cap tethered and loose. The only way I knew something was wrong was that I took off with half tanks and once I leveled off and looked my gauge registered full. It took a moment to figure out what was happening but then I turned around and landed. I found that tank mostly empty although the air pressure over the filler had lifted the sender to show full. There wasn't as much as a scratch on the wing.
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With no cap on the tank, would the air over the top, suck the fuel out?
Could be bad if it does but also causes the sensor to read full.
 
SixPapaCharlie said:
With no cap on the tank, would the air over the top, suck the fuel out?
Could be bad if it does but also causes the sensor to read full.
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Yup.. It is the way a airfoil works...... Pressure on top of a wing is low pressure.....
 
SixPapaCharlie said:
With no cap on the tank, would the air over the top, suck the fuel out?
Could be bad if it does but also causes the sensor to read full.
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Yes on the fuel, sensor depends on various factors exactly what it may do, but suffice it to say it may do anything.

I have for some undetermined reason developed a habit of looking at the back of the wings on climbout to look for streaming fuel. Not quite sure why I developed that habit....:rolleyes:
 
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