Long Term Storage of Hartzel Prop and Consequences

[mfleming]

Just a heads up for those that have a Hartzel propeller in long term storage or are considering buying a propeller thats been in storage.

Just a word of warning…

Hartzel told me when I bought my prop, that I had maybe two years before the grease separated and the seals would take a set. Then it would start slinging oil (separated from the grease).

They were right…my prop sat in a heated garage for just over two years before it was put in service and then started slinging grease pretty bad in less than a hundred hours.

The fix is to have the prop disassembled and resealed. In my part of the country, that costs $1,200.

So, think twice about buying a prop and end up havIng it sit for years OR buying someone else’s prop thats been sitting for years without factoring in the reseal costs.

 

[DiekerT]

Just a heads up for those that have s Hartzel prop in long term storage or are considering buying a propeller thats been in storage.

Just a word of warning…

Hartzel told me when I bought my prop, that I had maybe two years before the grease separated and the seals would take a set. Then it would start slinging oil (separated from the grease).

They were right…my prop sat in a heated garage for just over two years before it was put in service and then started slinging grease pretty bad in less than a hundred hours.

The fix is to have the prop disassembled and resealed. In my part of the country, that costs $1,200.

So, think twice about buying a prop and end up havIng it sit for years OR buying someone else’s prop thats been sitting for years without factoring in the reseal costs.

Is there anything one can do while it is in storage to prevent this?

 

[mfleming]

Is there anything one can do while it is in storage to prevent this?

Not that Hartzel or the prop shop could offer.

 

[dmattmul]

Just a heads up for those that have s Hartzel prop in long term storage or are considering buying a propeller thats been in storage.

Just a word of warning…

Hartzel told me when I bought my prop, that I had maybe two years before the grease separated and the seals would take a set. Then it would start slinging oil (separated from the grease).

They were right…my prop sat in a heated garage for just over two years before it was put in service and then started slinging grease pretty bad in less than a hundred hours.

The fix is to have the prop disassembled and resealed. In my part of the country, that costs $1,200.

So, think twice about buying a prop and end up havIng it sit for years OR buying someone else’s prop thats been sitting for years without factoring in the reseal costs.

Stored vertically or horizontally ? Rotated ?

 

[mfleming]

Stored vertically or horizontally ? Rotated ?

Mine was stored horizontally and supported as it was in the shipping box.

 

[rv8ch]

Do you recall the type of grease that was in the prop? I seem to recall that Aeroshell 6 was prone to separating more than Aeroshell 5, and the new grease they use, NYCO GN3058.

 

[bjdecker]

The first time I encountered this issue, I did the overhaul shop route - paid $850, etc…The second prop and the next time it happened, I purged the grease and replaced it with Aeroshell #5...no further issues.

The Nyco lithium grease isn't prone to separating like Aeroshell #6.

 

[mfleming]

The first time I encountered this issue, I did the overhaul shop route - paid $850, etc…The second prop and the next time it happened, I purged the grease and replaced it with Aeroshell #5...no further issues.

The Nyco lithium grease isn't prone to separating like Aeroshell #6.

So they say but mine had the Nyco grease and still separated out….severely.
The prop shop said it looked like the hub was packed with grey clay. Of course the clay is the binder in the grease.

 

[bjdecker]

So they say but mine had the Nyco grease and still separated out….severely.
The prop shop said it looked like the hub was packed with grey clay. Of course the clay is the binder in the grease.

Interesting - so instead of “brown goo” you had “grey goo”. I wonder if a simple purge with more NYCO would have saved you the $$$…

 

[mfleming]

Interesting - so instead of “brown goo” you had “grey goo”. I wonder if a simple purge with more NYCO would have saved you the $$$…

The prop shop had a cutaway of a hartzel prop and I don't see how pumping grease in one side would possibly push the old grease out the other side. Especially after separation and the clay binder being less fluid.

 

[Brantel]

Hartzell has long maintained that it is impossible to purge all the grease from their props without tearing them down.

 

[mfleming]

Hartzell has long maintained that it is impossible to purge all the grease from their props without tearing them down.

I can see why after looking at the cutaway

 

[rv8ch]

So they say but mine had the Nyco grease and still separated out….severely.
The prop shop said it looked like the hub was packed with grey clay. Of course the clay is the binder in the grease.

This is surprising - I thought that the change to nyco was to avoid this issue. Did you have the Nyco sticker on your prop?

 

[mfleming]

This is surprising - I thought that the change to nyco was to avoid this issue. Did you have the Nyco sticker on your prop?

Yes, it had the sticker.

 

[thehagg501]

Could you request to ship dry then add grease when needed?

 

[mfleming]

Could you request to ship dry then add grease when needed?

That would be a question for Hartzel. That might be a solution … $1200 reseal charge after a 100 hours of operation was pretty disappointing.

 

[jcarne]

Could you request to ship dry then add grease when needed?

I'll bet bucks they will say the grease wouldn't make it where it needed to go by only pumping it in and not packing the bearing first.

 

[bjdecker]

Not to be argumentative (bah - who am I kidding?), but 6 propellers on my home field have been fixed by purging - and the cutaway from the maintenance manual shows the grease path from zerk-to-drain. Maybe won’t get all the base out, but certainly enough to overcome the leaking and the loss of lubricant due to separation. Of course YMMV.

 

[jcarne]

Not to be argumentative (bah - who am I kidding?), but 6 propellers on my home field have been fixed by purging - and the cutaway from the maintenance manual shows the grease path from zerk-to-drain. Maybe won’t get all the base out, but certainly enough to overcome the leaking and the loss of lubricant due to separation. Of course YMMV. View attachment 62323

I think part of the worry is pumping massive amounts of grease into the hub cavity creating problems. I can't remember who posted it but someone that has a prop shop posted photos from over greasing, massive amounts of grease in the center hub cavity.

 

[Ironflight]

Not to be argumentative (bah - who am I kidding?), but 6 propellers on my home field have been fixed by purging - and the cutaway from the maintenance manual shows the grease path from zerk-to-drain. Maybe won’t get all the base out, but certainly enough to overcome the leaking and the loss of lubricant due to separation. Of course YMMV. View attachment 62323

I also hate to be argumentative, but in the interest of all those folks out there that are new to prop ownership, it should be noted that even A&P’s are not allowed to do anything to a certified prop except dress blades, and the prop shops that ARE allowed to work on them must maintain them to the factory manuals. I ‘d liek to see where in the Hartzell manual such an “in field flush” is described as an allowable procedure. Also….it is a major faux pas to mix different types of greases - if you do, Hartzell says you have to tear the prop down and have it cleaned and reassembled. So pumping in a different type of grease to replace the old stuff is bound to mix the two types - strike two (according to the Hartzell manuals.

Obviously, we’re talking experimental here, so you can pretty much do what you want - but the experts who designed and built the props would advise against what I think you’re describing. Caveat Emptor.

 

[bjdecker]

For the record — don’t mix greases — unless it’s Aeroshell 6 & 5, you can mix those, Per Hartzell service letter HC-SL-61-366, page 4.

Now, as to field greasing/purging there are a few service letters from Hartzell on the subject - strongly recommend that prop owners read them: specifically HC-SL-61-184…”Purging grease through the fittings is only 30% effective.” (…along with instructions…)

So it is documented, it’s old, and the NYCO update contradicts the purge verbiage….and it’s not very good.

 

[JonJay]

You did the right thing Michael. I know it was a pain and costly but you’re back in the saddle.

 

[dmattmul]

You did the right thing Michael. I know it was a pain and costly but you’re back in the saddle.

It's not like spitting grease takes one "out of the saddle". Mine spit grease for 15 hrs. Then slowed spitting and stopped. Spent 10 mins after each flight cleaning.

 

[mfleming]

It's not like spitting grease takes one "out of the saddle". Mine spit grease for 15 hrs. Then slowed spitting and stopped. Spent 10 mins after each flight cleaning.

Mine spit grease for over 15 hours. The way I looked at it was…was it getting better, staying the same or getting worse. Mine was getting worse. In hindsight, I know the grease was completely separated and it was slinging the oil out, leaving the clay binder behind.
I feel good about having the prop disassembled, cleaned and resealed.

 

[rmartingt]

Well

I ordered my prop in early 2020 thinking I'd be flying shortly (hah!). Probably got another year to go. It's been in a climate-controlled shop in the shipping box since then.

Anyone have recommendations for a prop shop around Atlanta, Savannah, Charleston, Jacksonville area...? If it's true the grease separates like that, I guess I'll ship in in after I get the spinner fitted. Or should I wait till it comes back to do that?

I'm aiming to move to the airport this fall.

 

[rv8ch]

I ordered my prop in early 2020 thinking I'd be flying shortly (hah!). Probably got another year to go. It's been in a climate-controlled shop in the shipping box since then.

Anyone have recommendations for a prop shop around Atlanta, Savannah, Charleston, Jacksonville area...? If it's true the grease separates like that, I guess I'll ship in in after I get the spinner fitted. Or should I wait till it comes back to do that?

Based on what I hear from the Savvy Aviation guys on the Ask the A&Ps podcast, I'd wait and fly it to see if there is an issue. If you ask a prop shop or Hartzell what you should do, they will of course tell you to do an overhaul or IRAN or re-grease. Mike Busch says that we are too quick to pull cylinders and to do prop work.

 

[JonJay]

Based on what I hear from the Savvy Aviation guys on the Ask the A&Ps podcast, I'd wait and fly it to see if there is an issue. If you ask a prop shop or Hartzell what you should do, they will of course tell you to do an overhaul or IRAN or re-grease. Mike Busch says that we are too quick to pull cylinders and to do prop work.

I agree, but five years is a long time for any mechanical piece of equipment to sit. It’s already pushing the calendar time, which is another conversation that’s been thrashed out here, and would prompt rolling eyes from Busch, and me….. i.e. don’t fix what ain’t broke….
However, I personally wouldn’t want to wait to find out and after all those years of building risk having to take the airplane out of service to have it resealed. That would kill me!
Positive - you get a fresh prop.
Negative- it costs you some dough.

 

[stigaro]

I admit I'm pretty naive to this whole thing, but is there enough movement of an installed prop to keep the grease in suspension? What is happening when in use that isn't happening in storage that would result in the grease remaining in suspension and the seals not drying out? I just received my prop a month ago and have probably a year before I install it.

 

[JonJay]

I admit I'm pretty naive to this whole thing, but is there enough movement of an installed prop to keep the grease in suspension? What is happening when in use that isn't happening in storage that would result in the grease remaining in suspension and the seals not drying out? I just received my prop a month ago and have probably a year before I install it.

I am no expert either but there is a lot of centrifugal force in a prop hub. The blades are also being hydraulically rotated.

 

[CharlesC]

I admit I'm pretty naive to this whole thing, but is there enough movement of an installed prop to keep the grease in suspension? What is happening when in use that isn't happening in storage that would result in the grease remaining in suspension and the seals not drying out? I just received my prop a month ago and have probably a year before I install it.

Me too, I don't know very much about these props at all, but, isn't there anything we can do to mitigate the problems of the grease separating and the seals drying out? I looked through the 3-ring binder that came with mine, and apart from the really difficult-to-follow storage requirements, I did not see anything applicable to our situation.
I've had the prop for going on a year now, and my engine build (according to Vans) is still about a year out. Seems like there should be something we could do. . .

 

[bertschb]

... isn't there anything we can do to mitigate the problems of the grease separating and the seals drying out?

I was wondering if rotating the orientation of the box every 3 months would help.

 

[Cessnadog]

I have a friend who built an -8. The prop sat in storage for 4-5 years before it went into service. It did sling grease and need a rebuild, but not until it had been in service for 10 years or so. I will wait and see how mine plays out. All I can do now is keep it dry and cool.

 

[BigBadBob]

I was wondering if rotating the orientation of the box every 3 months would help.

That's what I'm doing. I don't know if it will help, but I don't see how it could hurt. Works with paint in cans...

 

[dmattmul]

I was wondering if rotating the orientation of the box every 3 months would help.

And storing horizontally vs vertically a factor. Seems would make a difference?

 

[rv8ch]

And storing horizontally vs vertically a factor. Seems would make a difference?

My prop box said to store and ship horizontally, in a particular orientation, which is what I did. No grease leaks. Aeroshell 5. Stored for quite a while in my cool (5c-20c) basement.

 

[mfleming]

-----------------SNIP---------------- All I can do now is keep it dry and cool.

After having the grease separate in mine, I think keeping the prop cool in storage may be the key. I know that during my build when I was doing canopy work, I let the garage get pretty warm. We've all seen grease guns leak oil in a hot garage...the prop is probably no different.

 

[dmattmul]

My prop box said to store and ship horizontally, in a particular orientation, which is what I did. No grease leaks. Aeroshell 5. Stored for quite a while in my cool (5c-20c) basement.

Can you or anyone else post the document that states shipping AND storage needs to be horizontal? Shipping yes due to possible damage but can't find anything on storage orientation. If horizontal would flipping it every 6 months be an advantage? If vertically would clocking it 120 degrees be an advantage? (I have several 3 bladed props in storage)

Did find that Hartzell gives a 4-year window for props stored in preferred ambient conditions which seem like most props stored inside would meet.

 

[TParker]

We don't, to my knowledge, specifically call out a requirement for storage orientation; that being said, the packing for shipping assumes an orientation and is arranged accordingly so use good judgement. Rotating the storage orientation is only working with gravity, which won't do enough to keep the grease mixed, and does nothing for the more immediate issue of the hub side seal no longer being pliable enough to conform to the blade side seal; I don't recommend rotating the storage orientation as an effective practice.

Did find that Hartzell gives a 4-year window for props stored in preferred ambient conditions which seem like most props stored inside would meet.

That is for propellers in preservation packaging, rather than standard packaging; most RV buyers won't have a propeller that arrives in preservation packaging.

 

[mstrauss]

We don't, to my knowledge, specifically call out a requirement for storage orientation; that being said, the packing for shipping assumes an orientation and is arranged accordingly so use good judgement. Rotating the storage orientation is only working with gravity, which won't do enough to keep the grease mixed, and does nothing for the more immediate issue of the hub side seal no longer being pliable enough to conform to the blade side seal; I don't recommend rotating the storage orientation as an effective practice.


That is for propellers in preservation packaging, rather than standard packaging; most RV buyers won't have a propeller that arrives in preservation packaging.

"preservation packaging", can you please expand on what this is, and if it is something that can be added after the fact?

 

[TParker]

"preservation packaging", can you please expand on what this is, and if it is some that can be added after the fact?

It's detailed in Manual 202A, Volume 7 on our website. In short, the propeller hub and cylinder area is wrapped with a corrosion inhibited wrapper, then the whole thing is packed with desiccant and wrapped with corrosion inhibitor treated shrink wrap that is then carefully sealed with a torch.

While you could repackage your propeller with the same materials and procedures as the preservation packaging instructions after receiving it, this does not count as having been shipped in preservation packaging.

 

[dmattmul]

Rotating the storage orientation is only working with gravity, which won't do enough to keep the grease mixed, and does nothing for the more immediate issue of the hub side seal no longer being pliable enough to conform to the blade side seal; I don't recommend rotating the storage orientation as an effective practice.


That is for propellers in preservation packaging, rather than standard packaging; most RV buyers won't have a propeller that arrives in preservation packaging.

Which obviously begs the question what is the root cause of grease separation since very little "keep the grease mixed" is done with the use of "preservation packaging"?

Getting 4 years to have your prop idle would be relevant to a lot of RV builders. The current 2-year recommendation (Using non-preservation packaging) is tight for most builders. Does corrosion inhibit wrapping help with grease separation? I am not looking for Hartzell's 4-year warranty for my current props but would like to store my prop in the most suitable environment to reduce the effect of grease separation and if bagging the prop and fill with desiccant bags helps this issue would/could do it.

Appreciate everyone's input.

 

[raabs]

My harzell two blade (rv-10 ) new in storage 5-6 years. Shipped 2018. Ready to install and fly this summer.

Checked an Orlando prop shop, $2150 to reseal there. Checking some others. Likely Aeroshell 5? Likely best to reseal and not try..

Lot of clams to budget if your storing it. Any recommendations on FL shops? Or I can fly it in my 182 to somewhere farther. I'm in Central FL.

 

[TParker]

My harzell two blade (rv-10 ) new in storage 5-6 years. Shipped 2018. Ready to install and fly this summer.

Checked an Orlando prop shop, $2150 to reseal there. Checking some others. Likely Aeroshell 5? Likely best to reseal and not try..

Lot of clams to budget if your storing it. Any recommendations on FL shops? Or I can fly it in my 182 to somewhere farther. I'm in Central FL.

We have two recommended service facilities in Florida. At 5-6 years, definitely recommend a reseal before flying. Your propeller almost certainly has Aeroshell 6 in it rather than NYCO; NYCO was introduced in the production line in January of 2020.

 

[TParker]

Which obviously begs the question what is the root cause of grease separation since very little "keep the grease mixed" is done with the use of "preservation packaging"?

Getting 4 years to have your prop idle would be relevant to a lot of RV builders. The current 2-year recommendation (Using non-preservation packaging) is tight for most builders. Does corrosion inhibit wrapping help with grease separation? I am not looking for Hartzell's 4-year warranty for my current props but would like to store my prop in the most suitable environment to reduce the effect of grease separation and if bagging the prop and fill with desiccant bags helps this issue would/could do it.

Appreciate everyone's input.

Let me first say that I (and others here) are very sympathetic to this situation, this is not something we want builders to have as their first experience with their new prop. I wish I had clear, unambiguous guidance to give to prevent this. But unfortunately, like many things in aviation, this gets complicated quickly. For us to have official guidance for alternative methods would require us to do some long term environmental testing, which would take time and money, and likely wouldn't be done in time to do any builders in this situation any good.

The official guidance is in Manual 202A, Volume 7. The blade seals are not the only seals in the propeller. We have calendar time as part of TBO because of things like seals aging out. Servicing the grease to remove the separated portion eventually ends up with poor quality lubrication. Resealing a propeller may be an annoying expense and chore, but ultimately the goal of the guidelines is to ensure a safe, well operating propeller.

Unofficially: Keep the prop in as temperature controlled an environment as possible (minimize temperature variation) in a sealed plastic bag, with desiccant. This replicates the parts of the preservation packaging that have the most chance of helping the seals and grease, namely creating a closed, consistent environment. This may help, it may not, your results may vary and its a risk you take and accept. Good luck.

 

[raabs]

This Harzell answer is a bit LOL. While understanding the current situation, to say that they won't pursue a solution to the issue because it won't be done for current builders and it costs time and money is shortsighted and bit selfish on the part of the company. I don't know TP and he's probably a super person and is stuck with this issue -this is to Harzell not you.

Successful companies that are truly Customer focused, would work on a solution for all newer customers that aren't yet having this issue but may. (How about spending some time and money formulating lubrication that won't separate in 1-3 years - which is 3+ years before the calendar TBO). This way new clients won't get this surprise.

I didn't know about this until I'm ready to put my prop on before calendar TBO. My quotes are $1800-$2500 for a reseal. If 1000 customers have this issue at an average of $2000 ea, we are spending $2,000,000 to address it, and it's always a new crop of customers coming with the issue for more $.

How about Harzell taking a deeper dive and spending some time and money so millions don't have to be spent after we purchase a very expensive piece? NYCO hasn't solved it.

 

[rmartingt]

(How about spending some time and money formulating lubrication that won't separate in 1-3 years - which is 3+ years before the calendar TBO). This way new clients won't get this surprise.

Unfortunately we homebuilders are but a drop in the bucket of Hartzell's sales. They aren't going to spend a bunch of money and time addressing something that only a tiny fraction of their customers (and some of their least-profitable ones at that) run into. It's not like it's costing them any money right now.

 

[Ironflight]

This Harzell answer is a bit LOL. While understanding the current situation, to say that they won't pursue a solution to the issue because it won't be done for current builders and it costs time and money is shortsighted and bit selfish on the part of the company. I don't know TP and he's probably a super person and is stuck with this issue -this is to Harzell not you.

Successful companies that are truly Customer focused, would work on a solution for all newer customers that aren't yet having this issue but may. (How about spending some time and money formulating lubrication that won't separate in 1-3 years - which is 3+ years before the calendar TBO). This way new clients won't get this surprise.

I didn't know about this until I'm ready to put my prop on before calendar TBO. My quotes are $1800-$2500 for a reseal. If 1000 customers have this issue at an average of $2000 ea, we are spending $2,000,000 to address it, and it's always a new crop of customers coming with the issue for more $.

How about Harzell taking a deeper dive and spending some time and money so millions don't have to be spent after we purchase a very expensive piece? NYCO hasn't solved it.

So we’ve got one of the top Hartzell engineers willing to participate here with REAL information (not speculation) and you want to laugh at him? Great way to drive away the experts…..

 

[raabs]

Not at him, as said. He is likely a brilliant person.

But yes at a concept of not pursuing a solution to an issue that costs customers millions of dollars because it takes time and money. Maybe they are actually looking at a longer term solution, who knows.

I certainly don't appreciate needing to spend $2000 to have it resealed well before calendar TBO. I'm sure others aren't thrilled either.

Maybe Harzell and Vans could put a big red notice when ordering a prop so buyers are informed of this? And at the same time pursue a solution? That sounds not too unreasonable?

Again, look at the money customers have to throw at this. How about charge $500 more for each new prop for the next 1000 customers at risk for this issue and then put the $500k towards a solution? Saves clients $1500. Win, Win.

Not laugh as much as shake of the head. Disappointed that it's not a more aggressive approach to a solution.

 

[N82VM]

This entire issue is no different than getting a bargain at the club wholesale store on a gallon of mayo. Just because it’s cheaper than the small jar’s doesn’t make it a deal if you can’t use it before it expires.

That said, don’t order the engine prop combo (gallon of mayo) just to save $1000. Buy in quantities and portions that you can actually consume.

 

[rocketbob]

As one can see, grease doesn't go where its needed around the circumference of the blade shank. These things rotate less than 1/8" of inch in service and if Hartzell was really interested in improving their product they would use a DFL coating and avoid grease altogether. I would be willing to bet these things would work just fine without any grease.