McCauley 3 blade streaks. Defer, Iran, Overhaul?

[flyingchump]

I've had my E for a few months now and I'm starting to notice little grease/oil streaks going down 2 of the 3 blades.  I've seen worse but I don't know what acceptable amounts are... If any.   I'm not one to put off maintenance if something is needed.  Strange thing is most of the little streaks don't start at the base of the blades.  It looks like the spots start a few inches from the base and go out.  Is it flung up there?  Or am i just an idiot and these are bug guts or something?   The prop was new in 1998 and has not been overhauled or resealed since.  950 since new.  What do you all recommend?  Estimates on cost?  

Edited July 26, 2020 by flyingchump

[Ragsf15e]

I have same prop.  Mine was worse before my mechanic wanted me to dig into it more... actually, I started get a very fine mist on my windscreen.  Only noticeable during cleaning.  Streaks were worse than yours.  Mine was 14 years, 900 hours.  I got an overhaul.
 

Heres the thing, reseal would be best and probably sort it all out.  Your seals are likely old and leaking.  However, it’s unlikely you’ll find a prop shop that will do a reseal on a 22 year smoh prop.  They gonna overhaul it.  ~$5k.  They may find some corrosion in there too which will lead to overhaul.  When is your annual due?  You might be able to wait that long?  It’s down a couple weeks by the time you R&R, shipping, etc.

Standard disclaimer, only my experience, I’m not a prop guy.  But we have one with a great shop... @Cody Stallings

 

[flyingchump]

7 minutes ago, Ragsf15e said:

I have same prop.  Mine was worse before my mechanic wanted me to dig into it more... actually, I started get a very fine mist on my windscreen.  Only noticeable during cleaning.  Streaks were worse than yours.  Mine was 14 years, 900 hours.  I got an overhaul.
 

Heres the thing, reseal would be best and probably sort it all out.  Your seals are likely old and leaking.  However, it’s unlikely you’ll find a prop shop that will do a reseal on a 22 year smoh prop.  They gonna overhaul it.  ~$5k.  They may find some corrosion in there too which will lead to overhaul.  When is your annual due?  You might be able to wait that long?  It’s down a couple weeks by the time you R&R, shipping, etc.

Standard disclaimer, only my experience, I’m not a prop guy.  But we have one with a great shop... @Cody Stallings

 

It's really very minor.  The photos are after 6-7 hours of flight since I last cleaned the prop.  I'll probably wait a while.  My annual in due Feburary.  I plan on doing a few things this annual already and not another 5k for a prop overhaul...

I had the same feeling about an overhaul on a 22 y/o prop. 

[EricJ]

Find your propeller manual and see if it has guidance on what is acceptable.

 

[Cody Stallings]

New Oring an Gasket Kit would fix you up for another 22 years.

That leak may get worse, but at some point it will get better then stop all together. 
At that point it gets expensive because there is no grease left in the propeller an steel parts will start consuming each other.

Charging 5 AMU to O/H propeller is Bent Over the wing abuse!! 
Thats 2 AMU to High

 

[flyingchump]

35 minutes ago, Cody Stallings said:

New Oring an Gasket Kit would fix you up for another 22 years.

That leak may get worse, but at some point it will get better then stop all together. 
At that point it gets expensive because there is no grease left in the propeller an steel parts will start consuming each other.

Charging 5 AMU to O/H propeller is Bent Over the wing abuse!! 
Thats 2 AMU to High

 

I'm differently going to keep an eye on it and if she stops leaking, I stop flying. 

I hope your right about it costing 3 AMU for an overhaul.  I'd be much happier with that cost.

I've heard that east coast propellers is a good place to go.  Anyone have experience there? 

[47U]

I’ve got the 3-blade McCauley on my C.  I think McCauley recommends a 5 year overhaul.  It was first installed in 1990, then overhauled in 2000, I got the airplane in 2008 and overhauled it again in 2010.  It was about 2.5 amu.  

Now it’s 2020, another 10 years went by pretty fast.  Ameritech in Redding overhauled it in 2010, and they just picked it up last Friday, said it’d be back in 2 weeks.  And about 3.4 amu.  

He also said they’re now putting oil in the hub, not grease.  They made that change a couple years ago.  

tom

 

[Ragsf15e]

7 hours ago, Cody Stallings said:

New Oring an Gasket Kit would fix you up for another 22 years.

That leak may get worse, but at some point it will get better then stop all together. 
At that point it gets expensive because there is no grease left in the propeller an steel parts will start consuming each other.

Charging 5 AMU to O/H propeller is Bent Over the wing abuse!! 
Thats 2 AMU to High

 

I agree, price was excessive, but they also picked it up next day, and brought it back from California to Washington.  It was American in California (which probably affected the price).  It also had some minor corrosion and required shimming which I thought was pretty standard.  Other than the high $$, it came back fast and looked like new.

[47U]

On 7/26/2020 at 10:25 AM, 47U said:

I’ve got the 3-blade McCauley on my C.  I think McCauley recommends a 5 year overhaul.  It was first installed in 1990, then overhauled in 2000, I got the airplane in 2008 and overhauled it again in 2010.  It was about 2.5 amu.  

Now it’s 2020, another 10 years went by pretty fast.  Ameritech in Redding overhauled it in 2010, and they just picked it up last Friday, said it’d be back in 2 weeks.  And about 3.4 amu.  

He also said they’re now putting oil in the hub, not grease.  They made that change a couple years ago.  

tom

 

Well, my 30 year old McCauley will make it through the overhaul, but it needs teflon inserts in the hub because the blade o-ring seats are worn, about a 1 amu hit.  An option, I’m told, that wasn’t available up to just a couple years ago.  Sooooooo, I’m up to 4.9 amu.  Better than 10+(?) amu for a new prop, or a coupIe amu for a new hub.  I’m lucky I have an understanding comptroller... 

Last annual, the prop had some fore/aft play in one blade in particular, but it was within spec and didn’t show any evidence of throwing grease, ever.  I wonder if I’d delayed the overhaul and run it another year or three, if it would have worn enough that the teflon insert fix wouldn’t have been an option requiring a new hub.  When the teflon wears, that can be replaced.  I’ll have to ask how many hours they figure the teflon lasts.

Scheduled mx is sometimes expensive.  Deferring scheduled mx is sometimes more expensive.  The prop is under tremendous stresses. For me, having confidence in the prop is worth the piece of mind.  Besides, I just purple-polished the spinner.

[Cody Stallings]

.950hrs TT an Teflon Mod has to be done?

So I will ask agin in a different way:

So your 950Hr TT propeller with a Factory Recommenced TBO of 3000hrs has to have the Teflon Mod done at First disassembly.

This means your Blade Sockets in the hub are worn completely out, in only 950hrs!!!... Unheard of!

 

Perspective on this:

I have(Personally) a C505 McCauley propeller that is Just like your propeller except it feathers an has bigger blades. It lived a long life on a Cessna 414 before it was transplanted to a Real plane!!............................... Yes, a Real plane...;)

The blade to hub Union is the same as your propeller. Even uses the same blade Orings.

My hub has been in service long enough to be on its second set of blades.

As of two Yrs ago when it was pulled off to Check out an reseal cause I had just purchased the Plane it had a total of 6100hrs TT on the Hub.

Not looking at any logbooks I’m gonna venture a pretty responsible Guess that it has about 6400hrs TT on the hub now.

 

Guess who doesn’t have the Teflon Mod Yet!!

This guy.

Edited July 31, 2020 by Cody Stallings

[47U]

Cody... thanks for your expertise, though I think you’re mixing info between the OP and my post.  OP has 950 hrs his prop, new in 1988, and was throwing a little grease, mine is 30 yrs old on its 3rd overhaul and needs the teflon inserts.  It’s a little over 1400 hrs TTSN and 600 SMOH.

So, why is my hub worn after 1400 TTSN?  Corrosion?  There’s no external evidence of that, although it was in Northern Iowa (hangared on a farm strip) from new in 1990 until 2008 when I brought it out to NORCAL.  I’m hangared, albeit in a somewhat leaky T-hangar that the rain blows in some (Oct-Apr) through the fold up door.  Is the teflon insert mod good for another 10 years?  If I’m not experiencing any problems, should I extend the overhaul interval?  I was concerned last annual about the one blade with a little more wiggle than the other two... and it’d been10 years.  It’s that paranoia thing I got going for me.

Again, thanks for your expertise.  

tom

 

[carusoam]

Tom, @47U

It helps to throw @Cody Stallings an invite or quote what he said... this way he knows to stop by to see your question...

Best regards,

-a-

[Cody Stallings]

On 7/30/2020 at 7:10 PM, 47U said:

Cody... thanks for your expertise, though I think you’re mixing info between the OP and my post.  OP has 950 hrs his prop, new in 1988, and was throwing a little grease, mine is 30 yrs old on its 3rd overhaul and needs the teflon inserts.  It’s a little over 1400 hrs TTSN and 600 SMOH.

So, why is my hub worn after 1400 TTSN?  Corrosion?  There’s no external evidence of that, although it was in Northern Iowa (hangared on a farm strip) from new in 1990 until 2008 when I brought it out to NORCAL.  I’m hangared, albeit in a somewhat leaky T-hangar that the rain blows in some (Oct-Apr) through the fold up door.  Is the teflon insert mod good for another 10 years?  If I’m not experiencing any problems, should I extend the overhaul interval?  I was concerned last annual about the one blade with a little more wiggle than the other two... and it’d been10 years.  It’s that paranoia thing I got going for me.

Again, thanks for your expertise.  

tom

 

Oh Boy!!

Guess I Need to pay closer attention. Sorry about that.

Etching an Corrosion Rework is the #1 killer of McCauley Hub Blade Sockets.

During the O/H process(Very rough on a propeller) the aluminum parts are Dipped in Nitric Acid. 
That Acid chews a layer of material off the part.

With your propeller being etched 3 times that could be some of it.

Another possibility is during those O/H if there was some Corrosion in the sockets, that has to be worked out which opens up the tolerance more.

Then there is also the guy who falls asleep while working the corrosion or damage out with power tools....lol.. Kidding

 

[47U]

Thanks for your info, @Cody Stallings.  Sounds like the tolerances are pretty tight, if etching can have an affect.  Hopefully the teflon inserts are leak free, being there’s oil in the hub now.  

How about blades?  Absent any major nicks, how many overhauls can I expect before I need one or more blades replaced?  I do like getting a prop back that looks brand new, but I’m guessing there’s a cost to that, eventually.

tom 

[Cody Stallings]

1 hour ago, 47U said:

Thanks for your info, @Cody Stallings.  Sounds like the tolerances are pretty tight, if etching can have an affect.  Hopefully the teflon inserts are leak free, being there’s oil in the hub now.  

How about blades?  Absent any major nicks, how many overhauls can I expect before I need one or more blades replaced?  I do like getting a prop back that looks brand new, but I’m guessing there’s a cost to that, eventually.

tom 

The Teflon is really look about holding oil/Grease back, you should have any issues in that union.

Yes, the Etching process is pretty rough. Doesn’t take long to open up some clearances.

Well normally you will get about 4 O/H out of a set of blades. Sometimes a 5th but not very often depending on blade design.

Dont always have to O/H to make them look like new. An IRAN can give the same visual appeal, an not be nearly as rough to the propeller Components.

[carusoam]

Let’s flip the table upright....

Great additional details, Cody!

-a-

 

[M20F-1968]

On 7/26/2020 at 12:09 PM, flyingchump said:

I'm differently going to keep an eye on it and if she stops leaking, I stop flying. 

I hope your right about it costing 3 AMU for an overhaul.  I'd be much happier with that cost.

I've heard that east coast propellers is a good place to go.  Anyone have experience there? 

My prop is at New England Propeller in CT now.  Spoke with several people who recommended them.  $2600.00 was quoted.  They even picked it up for me.  

John Breda

[flyingchump]

Thanks.

Will you let me know how it all worked out when you get you prop installed?