A small surprise at annual.

[Guest Mike261]

My plane will be coming out of annual monday, an expensive annual. I got off easy last year, but this year i needed mags, brakes and some other items that pushed the price close to the dreaded 10k annual. one of the items was not annual related per se, I sent the AI to bob bramble for overhaul. It is part of the overall maintenance costs, and i had it done during the annual.

The little surprise was the oil cooler hose fitting that is on the outboard side. it has been chafing from contact with the cowling. I don't know how long this has been going on, but it would have eventually went completely through the aluminum fitting and vented the oil to the engine compartment. the amount of material missing from the fitting was alarming. the fact that the cowling wasn't chafed right through is puzzling, i guess the fitting is considerably softer.

My mechanic remedied the situation and swung the fitting to be further away from the cowling.

YMMV, but you may want to check yours...

this begs the question... why do i have hydraulic fuses on my washing machine lines that i bought at home depot, but none on the oil cooler lines that can kill me?

 

Mike

[carusoam]

I looked up The Rockwell hardness of the two metals.  Since both are alloys, a blend of materials, not pure aluminum 'pure brass' if that existed...

They are both soft.  They are listed as a range of hardness on Rockwell's B scale.  The harder metal will wear the softer metal unless they are both similar in hardness.

Brass B55-93

aluminum B28-91

The softer the alloy, the quicker it will wear.

Glad you caught the issue before the oil got out.

Do you have any pictures? (Please) 

Best regards,

-a-

[Guest Mike261]

no pics. i didn't even think to take one. i always neglect to take pictures, somehow its never registered with me that i always have a camera in my pocket. If he still has the fitting around, i will get a shot.

mike

[Johnnybgoode]

21 minutes ago, Mike261 said:

this begs the question... why do i have hydraulic fuses on my washing machine lines that i bought at home depot, but none on the oil cooler lines that can kill me?

 

Mike

Simple. Since the FAA doesn't regulate the parts on your washing machine, they probably are quite reasonably priced.

[Guest]

I don't think you can hang this one on the FAA, possibly the original installer and those who have done the subsequent inspections and missed it until this year.

Clarence

[N201MKTurbo]

2 hours ago, carusoam said:

I looked up The Rockwell hardness of the two metals.  Since both are alloys, a blend of materials, not pure aluminum 'pure brass' if that existed...

They are both soft.  They are listed as a range of hardness on Rockwell's B scale.  The harder metal will wear the softer metal unless they are both similar in hardness.

Brass B55-93

aluminum B28-91

The softer the alloy, the quicker it will wear.

Glad you caught the issue before the oil got out.

Do you have any pictures? (Please) 

Best regards,

-a-

And the glass in the fiberglass cowl is about twice as hard as both...

[jetdriven]

Right on that, aluminum that chafes against fiberglass will get sawn up in a hurry.  

Edited March 14, 2016 by jetdriven

[Guest Mike261]

2 hours ago, M20Doc said:

I don't think you can hang this one on the FAA, possibly the original installer and those who have done the subsequent inspections and missed it until this year.

Clarence

he was hanging the fact that there aren't hydraulic fuses in the oil lines on the FAA, not the chafing. And it was a rhetorical question on my part, we all know he is right. it seems silly that you can't have a simple check valve on the return line and a hydraulic fuse like on my washing machine hose on the supply side, ahead of the hoses. they are cheap anywhere else. after the crash of flight 232 into the cornfield they started installing them in the control systems of jets. your oil temperature will of course rise, but you get a warning and time, maybe you can adapt and conquer. jettison all the oil through a chafed fitting or broken hose and you're in a world of hurt. I never really even thought of it until i had the chafed fitting. i'll bet a nickel that more than once this has happened.

mike

 

[N201MKTurbo]

Just a side note...

I had a weird failure once with my F. The alternator fan flew apart and a piece of it hit the oil cooler. The engine made a loud bang when it happened. I was over inhospitable country, but luckily there was an airport near by. It took about 5 min. to land (the engine was still running fine). There was oil all over the right side of the plane. There was only 2 Qts left in the engine.

All that oil came out of a hole about 1/16 x 1/8 inch.

[Guest]

While a hydraulic fuse may be a wonderful idea, and has its uses.  I can already hear the CB club screaming with protest " the over reaching FAA is forcing me to spend  XXXX to install this part because someone couldn't see a chaffed oil fitting on the top of a J model engine.

Clarence

[Yooper Rocketman]

Any time my cowl is off I am looking for potential problems.  Chad, my local FBO operator, A&P/IA, operates the same way.  We have found issues many times during routine maintenance that could have led to more serious problems later (I'm not talking during annuals either).  Steve, my hangar partner with E model will sit on a stool and just scan the engine compartment anytime one of our planes is de-cowled.  He's the one that taught me that habit.  I'm not real anxious for the FAA to mandate "airline standards" to my Part 91 operations.  That could become real expensive leading to a further decline in GA.  If someone wants extra equipment for safety on their plane, there is always the 337 route to making it happen.

 

[N201MKTurbo]

This hydraulic fuse thing is BS. As you can see from my post above, my engine was going to quit in a few minuets from a leak that wouldn't trip a hydraulic fuse. The leak caused by a chafing fitting would start extremely small and wear bigger. it would not trip the hydraulic fuse before you ran out of oil.

The only thing a hydraulic fuse will protect you from is a complete breach of a pressurized hydraulic line. If you have ever tried to cut an aircraft hose you will know that is very unlikely.

[Johnnybgoode]

20 minutes ago, N201MKTurbo said:

This hydraulic fuse thing is BS. As you can see from my post above, my engine was going to quit in a few minuets from a leak that wouldn't trip a hydraulic fuse. The leak caused by a chafing fitting would start extremely small and wear bigger. it would not trip the hydraulic fuse before you ran out of oil.

The only thing a hydraulic fuse will protect you from is a complete breach of a pressurized hydraulic line. If you have ever tried to cut an aircraft hose you will know that is very unlikely.

My point was not in an FAA mandate, just disdain for their hinderance to allowing reasonable modification, where deemed appropriate. Perhaps my RV-4 ownership has clouded my vision...but I think not.

Patrick

[Guest Mike261]

7 hours ago, N201MKTurbo said:

This hydraulic fuse thing is BS. As you can see from my post above, my engine was going to quit in a few minuets from a leak that wouldn't trip a hydraulic fuse. The leak caused by a chafing fitting would start extremely small and wear bigger. it would not trip the hydraulic fuse before you ran out of oil.

The only thing a hydraulic fuse will protect you from is a complete breach of a pressurized hydraulic line. If you have ever tried to cut an aircraft hose you will know that is very unlikely.

I don't like your tone. I already explained it was a somewhat rhetorical question. Instead of offering your input in a constructive way, you preface your statement like a Troll.

mike

[dfswing2]

I'm with Yooper.  Anytime I have the cowl off I inspect it for chaffs and deposits.  I then clean both the upper and lower sections before reinstalling it so that I can inspect the next time.

[N201MKTurbo]

1 hour ago, Mike261 said:

I don't like your tone. I already explained it was a somewhat rhetorical question. Instead of offering your input in a constructive way, you preface your statement like a Troll.

mike

You are right, I apologize. I had been setting in the lobby of the urgent care place down the street with a banged up knee for over three hours, I was in a pissy mood...

[kortopates]

1 hour ago, Mike261 said: I don't like your tone. I already explained it was a somewhat rhetorical question. Instead of offering your input in a constructive way, you preface your statement like a Troll.

mike

You are right, I apologize. I had been setting in the lobby of the urgent care place down the street with a banged up knee for over three hours, I was in a pissy mood...

Wow - sorry to hear about the knee. Hope it gets better soonest!

Sent from my iPhone using Tapatalk

[Yooper Rocketman]

2 hours ago, Mike261 said:

I don't like your tone. I already explained it was a somewhat rhetorical question. Instead of offering your input in a constructive way, you preface your statement like a Troll.

mike

Hey, don't be picking on my Lower Michigan friends.  We're called Yoopers in the U.P. (Upper Peninsula of MI), and we call the guys below the bridge (Mackinaw Bridge), Trolls.

[N201MKTurbo]

21 minutes ago, kortopates said:

Wow - sorry to hear about the knee. Hope it gets better soonest!

Sent from my iPhone using Tapatalk

Thanks, spectacular bicycle crash! Chain came off the front sprocket while I was putting 110% power to the pedals off the seat. Right foot came down hard, unclipped, thigh hit the top tube with great force then me and the bike skidded into a curb at about 27 MPH!

[kortopates]

Ouch!! I can't even imagine the pain and I am an avid MTB rider myself. Great cardio. Hope there is no long term damage.

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[MyNameIsNobody]

2 minutes ago, N201MKTurbo said:

Thanks, spectacular bicycle crash! Chain came off the front sprocket while I was putting 110% power to the pedals off the seat. Right foot came down hard, unclipped, thigh hit the top tube with great force then me and the bike skidded into a curb at about 27 MPH!

As I have gotten older I seriously think about goofy stuff like that happening...So I don't ever get off my seat.  I hope you recover quickly and fully.  Sorry this happened.  That sucks when you are trying to do something for health and fun and you get nailed by a freakish failure

Here's to 110% recovery

 

[MyNameIsNobody]

27 minutes ago, Yooper Rocketman said:

Hey, don't be picking on my Lower Michigan friends.  We're called Yoopers in the U.P. (Upper Peninsula of MI), and we call the guys below the bridge (Mackinaw Bridge), Trolls.

Some great times had chasing birds by Traverse City.  Some not so great times at Grayling...Always fun at Traverse City Holiday Inn though!

[Guest]

24 minutes ago, N201MKTurbo said:

Thanks, spectacular bicycle crash! Chain came off the front sprocket while I was putting 110% power to the pedals off the seat. Right foot came down hard, unclipped, thigh hit the top tube with great force then me and the bike skidded into a curb at about 27 MPH!

If it's still sore in the morning perhaps Marauder could send one of the girls over to tend to your injuries.  Marauder, any of the girls with medical experience?

Hope you recover soon.

Clarence

[Marauder]

24 minutes ago, N201MKTurbo said: Thanks, spectacular bicycle crash! Chain came off the front sprocket while I was putting 110% power to the pedals off the seat. Right foot came down hard, unclipped, thigh hit the top tube with great force then me and the bike skidded into a curb at about 27 MPH!

If it's still sore in the morning perhaps Marauder could send one of the girls over to tend to your injuries.  Marauder, any of the girls with medical experience?

Hope you recover soon.

Clarence

When I first read about his banged up knee all I could think was that he made the rookie mistake of...

trying to lift one of these beauties.

Glad to hear no plus sizes were injured. Also happy to hear it was only a banged up knee. A chain break could have easily put him over the handle bars head first.

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[Yooper Rocketman]

17 minutes ago, Marauder said:

When I first read about his banged up knee all I could think was that he made the rookie mistake of...

trying to lift one of these beauties.

Glad to hear no plus sizes were injured. Also happy to hear it was only a banged up knee. A chain break could have easily put him over the handle bars head first.

Sent from my iPad using Tapatalk

I always wondered what your back side looked like.   I see you took the light weight on this one!

tom