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You will not get a consensus on this question. The only "100%" safe thing to do is to send it out for an IRAN. If you have the money and time, there is little downside to an IRAN. Mike Busch would probably say just fly it, since he says that there are very, very few cases of a prop like this causing an off-field landing.
 
Agree that an IRAN is the most severe action you should take. An overhaul process REQUIRES that you replace certain hardware and grind the surface of the blades. No sense in either one since all you are really concerned about is the unlikely event of severe unseen corrosion which might compromise the structure of the blade.
 
Agree with previous posters ;)

No pics of the blades, but the hub looks in pristine condition.
Were it mine (I shall repeat, mine), I'd service it, e.g. grease it as it says in the manual. If I recall correctly (no time for me to recheck right now) one has to remove 2 of the grease nipples, and apply the stuff to the remaining 2, until it oozes out. A look at what is coming out would decide... lots of air, water, grease and water, darkly coloured grease => IRAN or OH. Blond grease with none of the above, I'd fly it for say 100h (or 1 year) and observe. No grease leaks, I'd probably go to 500h and then send it in for OH. Again, that's only me...
 
Doesn’t add up to me.
If that prop is 20y old and actually flown more than a handful of hours I’d say that it looks like the crime scene cleaners have been in attendance.
Wrt to the greasing then I respectfully suggest that it’s just two squeezes and that it for the grease. If you push till it squeezes then. It’s too much. Usual caveats about grease type etc. RTM. It’s online and free.

To be blunt - if it’s as old as you say and there’s no paperwork to suggest otherwise then you are absolutely on your own wrt to its internal condition - actual flight hours or not.

Looks to me like the previous owner(s) were either absolutely fastidious with their maintenance and cleanliness (and paperwork….) or that airplane has been in witness protection since birth.
Got any pics of the blades?
 
Mine was slinging grease regularly at 12 years old and about 700 hours. I removed it, had American Propeller in Redding pick it up. Got it back, reinstalled it, no longer slings grease. New paint, seals, logbook.
 
There are many stories of internal corrosion on C/S props - what percentage I have no clue. There is plenty of moisture available on the engine oil side of the internals in the hub.

It all comes down to comparing the cost of O/H vs the risk of something even more expensive happening inside there.
 
At the very least, you want to do an IRAN reseal.

there’s a good possibility that there are service bulletins on the prop that the overhaul may be the better option. Your local prop shop would be the one to ask.

when I sent my prop in for an overhaul with over 2000 hours on it, there was a service bulletin to shot peen the shanks of the blades. That is something that would get overlooked if it was just tear down reseal.
 
I had some rock chips that I had feathered out and was pondering the same thing on my 10 year old Hartzell. What did I do? Took it off and spent $4400 having it overhauled. Auburndale prop shop assured me the paint would be as good as when Hartzell shipped it the first time. After 2 hours of flying (no rain) and both blades looked like this. They said the inside looked great and had no corrosion. I can’t tell you what to do but I wish I had done something different. The prop shop is happy to warranty the paint after I remove the prop for them…
 

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I just had mine overhauled after 12 years (since new) on my -4. It looked as clean as yours and I, too, debated whether to do anything or keep flying it. I wanted to do an IRAN, but the prop repair facility my FBO used would only overhaul it. If I had had more time, I would have shopped around for a place that would perform an IRAN.

For a 20 year old prop, I would go the IRAN route in lieu doing nothing. Before that, however, I would recommend you call Hartzell with blade and hub S/Ns in hand and ask them if there are any issues that need to be addressed. I have found Hartzell's tech help line to be very helpful.

Best of luck,
 
Just had mine done. $3500. 10 year calendar. Prop shop said it looked great but the seals had started to degrade. They said I could have probably gone a year or two more before it started slinging grease.
Rubber only lasts so long even in ideal conditions.
I’m willing to stretch the calendar times on overhauling components, but 20 years is a big stretch.
 
I had my prop resealed last year by APW in Auburndale - ~$3000 which included a dynamic balancing session. IIRC the calendar limit on Hartzells is 7 years.
 
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Dan 57 said:
Agree with previous posters ;)

No pics of the blades, but the hub looks in pristine condition.
Were it mine (I shall repeat, mine), I'd service it, e.g. grease it as it says in the manual. If I recall correctly (no time for me to recheck right now) one has to remove 2 of the grease nipples, and apply the stuff to the remaining 2, until it oozes out. A look at what is coming out would decide... lots of air, water, grease and water, darkly coloured grease => IRAN or OH. Blond grease with none of the above, I'd fly it for say 100h (or 1 year) and observe. No grease leaks, I'd probably go to 500h and then send it in for OH. Again, that's only me...
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I too would service it and fly it. Then if it starts to sling grease, I would consider a reseal. Just to clarify your service memory, you do NOT pump grease until it comes out.. that’s a sure way to over service it. The procedure for tractor props (as opposed to pusher props) is to remove the trailing edge grease fittings, clean inside the hub with a piece of safety wire to free up or break up any hardened grease, then grease the ones at the leading edge by pumping in ONE ounce or stop short of one ounce if it comes out the other side. You do NOT keep pumping for it to come out the other side. One ounce is about 6 pumps with a hand operated grease gun.
page 6-7 or page 223 of 276
 
Looks far too good to be 20 years old!
It is the internal corrosion that will cause problems.
I would suggest an IRAN.
 
Old aviation proverb: if it ain't broke, don't fix it.

I've had more problems doing preventative service on items than those I waited for signs of an issue. Obviously different functions require different parameters. My Hartzell CS prop is still running well, no leaks after 19 years, 960 hours. I grease every condition inspection per Hartzell instructions. In my case its AeroShell #6, six pumps from a grease gun into the grease fittings at the leading edge. As you'd expect, plenty of old, dirty grease pops out the other side. Finish by cleaning out any residual with a little piece of safety wire. Reinstall the two grease fittings removed for the service and their caps and you're good to go.

Chris
 
I pumped til it came out clean on the opposite side. At least 7 times. 1300+ hours. Troublefree.
My Hartzell manual states 6 years. Paid to have it overhauled at 6 years.
My A** is sitting in it 2 miles above the ground. I don’t think it’s a place to save Pennie’s or dollars. Peace of mind.
Just airplane dollars. Gotta expect to pay em to someone.
Lotsa info & opinions on the internet. Misinformation???
 
pilotkms said:
I pumped til it came out clean on the opposite side. At least 7 times. 1300+ hours. Troublefree.
My Hartzell manual states 6 years. Paid to have it overhauled at 6 years.
My A** is sitting in it 2 miles above the ground. I don’t think it’s a place to save Pennie’s or dollars. Peace of mind.
Just airplane dollars. Gotta expect to pay em to someone.
Lotsa info & opinions on the internet. Misinformation???
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So why did you pump it till it came out clean on the other side? This is not recommended by Hartzell.
 
A couple of comments.
Hartzell manual specifies a max amount of grease to be put in, in ounces. Over greasing is bad.
Hartzel has gone to a new grease (Nyco?) but it is not compatible with Aeroshell 5 or 6, which is most likely what you have in a 20 y.o. prop. Use the new grease only if the prop has been disassembled and cleaned.
Hartzell will sell you ‘plugs’ (bolts) to replace the zerk fittings that are only used as plugs and need to be removed every greasing. They are dirt cheap compared to most aviation products, shipping costs far more. Get two, replace the zerks that you never use for applying grease. Much easier on-off, removes all confusion as to what gets removed (assuming you get it right the first time).
 
pilotkms said:
I pumped til it came out clean on the opposite side. At least 7 times. 1300+ hours. Troublefree.
My Hartzell manual states 6 years. Paid to have it overhauled at 6 years.
My A** is sitting in it 2 miles above the ground. I don’t think it’s a place to save Pennie’s or dollars. Peace of mind.
Just airplane dollars. Gotta expect to pay em to someone.
Lotsa info & opinions on the internet. Misinformation???
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Pumping till it comes out the other side is NOT correct. Look at my post a few up.. I posted the manual with the page number on the procedure. Pumping till it comes out the other side IS misinformation. Although if you only did 7 pumps, at least you didn’t over service it by TOO much..
 
chrispratt said:
Old aviation proverb: if it ain't broke, don't fix it.

I've had more problems doing preventative service on items than those I waited for signs of an issue. Obviously different functions require different parameters. My Hartzell CS prop is still running well, no leaks after 19 years, 960 hours. I grease every condition inspection per Hartzell instructions. In my case its AeroShell #6, six pumps from a grease gun into the grease fittings at the leading edge. As you'd expect, plenty of old, dirty grease pops out the other side. Finish by cleaning out any residual with a little piece of safety wire. Reinstall the two grease fittings removed for the service and their caps and you're good to go.

Chris
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If you are getting “plenty of old grease” out the other side, you aren’t doing it “per the manual”
 
After 20 years I would IRAN the prop. You would essentially start out with a new prop.

Question is what are you going to do?
 
If you can, it would be really interesting to get a lot of photos from inside the hub when they take it apart.
 
Dean Pichon said:
That is part of my frustration. The log book only indicated it was overhauled. When I called the shop after I received (and paid for) the prop, they were not interested in reviewing the records to tell me what they found or did.
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I had the same issue with an engine overhaul shop. They did the work in the past. I called to see if I could get a copy of the paperwork, and their single-word response: "No."

Why even have records? What is their purpose if the owner of the aircraft with the engine or prop can't see them?
 
SquawkVFR said:
I'm hoping I can arrange an agreement with the shop before sending my prop in where they'll document fidnings and take before/during/after pics. Even if I have to pay a little extra for that service, it seems worth it to me.
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Absolutely. This is something that should be negotiated and agreed in writing before hand. If you want to go all the way, include financial penalties if they don't actually do it.
 
SquawkVFR said:
Well, my local Hartzell-approved prop shop doesn't advertize IRAN as a service on their website. I talked to them this week, and they're supposed to get back to me about my options. I'll follow up next week, but right now, I'm leaning toward the overhaul. I've read about the fact that there's no way to inspect a CS prop for corrosion. The frequency with which this plane has been flown seems to me to be an ideal way to maximize the opportunity for corrosion (only flown a few hours a year). I've also read about how CS props fail, and it doesn't sound very survivable to me. Not worth the risk IMO.
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Might be that the IRAN process is sometimes referred to as a "re-seal" when it comes to propellers.

After mine started slinging a slight bit of grease (@ 10+ years since manufacture, and ~1000 hours flying) I sent it in (American Propeller, Redding CA). They accepted it as a re-seal. The tear-down, cleanup, inspection, re-assembly, painting and static balancing was exactly the same for the re-seal vs. an overhaul. The difference was that only parts that failed inspection were replaced (the ball bearings in my case), with everything else being re-used. An "overhaul" has a specific list of parts from the prop manufacturer that MUST be replaced, regardless of condition.

It is possible to start with a re-seal process and proceed to a full overhaul if the prop condition requires it. The only difference is more parts replaced.....which means more $$$. 😨 I have heard of prop shops refusing to do anything less than a full overhaul. No idea what the reasons were. Age of the prop?....experimental vs type certificated airplane?......don't know.

And yes, in my case all the specific work to be done was written up with an initial estimate and signed before they received the prop (by the pickup/delivery driver actually). After the inspection I receive an updated quote (because of the bearings needing to be changed out), which was the final price. No $$$ surprises after the fact. Kind of the way it should work ;).
 
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ronrapp said:
I had the same issue with an engine overhaul shop. They did the work in the past. I called to see if I could get a copy of the paperwork, and their single-word response: "No."

Why even have records? What is their purpose if the owner of the aircraft with the engine or prop can't see them?
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Records are required of faa repair stations. But they are also used in litigation, so most shops won’t release them without a court order. But the owner of record should have received a copy.
 
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