Prop Grease seals leaking?

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drotto

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drotto
It seems like the gasket on my prop governor is leaking a tiny bit. I have gotten a small amount of oil splatter around the routes of the blade two of the last three flights. I am well aware this needs to be fixed. At this time the plane flies fine. Runs great. Oil pressure is normal, and the engine oil checks out on pre flight, and does not show any loss.

Are these gaskets prone to catastrophic failure? How much time is involved in Getting them fix? Could anything else cause a small amount of oil on the blades?

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Are you sure your not talking about the grease seals in the hub?
 
Chip Sylverne said:
Are you sure your not talking about the grease seals in the hub?
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Sorry, yes it is likely the grease seals. It is leaking right around where the route of the blade is attached.

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Send that prop to the prop shop for a re-seal. Grease coming out of the blade root, means someone has over greased it and have blown the seal.
 
Tom-D said:
Send that prop to the prop shop for a re-seal. Grease coming out of the blade root, means someone has over greased it and have blown the seal.
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Can any shop fix it or does the prop need to go out to a specific shop? The prop only has about 450 hrs on it.

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drotto said:
Can any shop fix it or does the prop need to go out to a specific shop? The prop only has about 450 hrs on it.

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Any reliable prop shop should be able to do it.
 
drotto said:
Can any shop fix it or does the prop need to go out to a specific shop? The prop only has about 450 hrs on it.

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I believe it needs to go to a prop shop for the re-seal.

If you choose to keep flying, keep in mind in a single failure the blades go flat pitch in a twin failure they feather.
 
Is the grease red in color? The PA-32-301 I flew a long time ago had a small amount of red grease seeping out onto the blades. The A&P declared it normal. Sorry, I don't know how many hours it had on it. -Skip
 
@drotto I see you are in NJ. I used East Coast Propeller recently in PA for a double overhaul on my props and highly recommend them if you don't have a shop in mind. They pick up and deliver to your shop.
 
Skip Miller said:
Is the grease red in color? The PA-32-301 I flew a long time ago had a small amount of red grease seeping out onto the blades. The A&P declared it normal. Sorry, I don't know how many hours it had on it. -Skip
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The plane is a PA32R-301 should have mentioned that. Not exactly sure on the color but is seems to be a liight brown to maybe slightly red color when I wiped it off. It looks overall very clean, not like oil in need of changing or contaminated. Like i said is is a very small amount in dots or a small splatter near the route of the blade. At this point no effect on the plane performance.

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drotto said:
The plane is a PA32R-301 should have mentioned that. Not exactly sure on the color but is seems to be a liight brown to maybe slightly red color when I wiped it off. It looks overall very clean, not like oil in need of changing or contaminated. Like i said is is a very small amount in dots or a small splatter near the route of the blade. At this point no effect on the plane performance.

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Mine started slow with a few small dots/splatters. I wiped clean and continued flying a bit. After a few flights it puked quite a bit out and the shop said they had to pull them and send them in. It had been several years since overhaul so none of the prop shops were willing to just re-seal so I did the full overhaul on them. They came back zero time looking brand new. The seal's were essentially dry rotting from time/exposure. How many years are on the prop? Mine had about 400 hours but close to 15 years as the previous owner wasn't flying enough. They are McCauly's. If you don't have too many years on them they will just re-seal for much cheaper than overhaul.
 
Radar Contact said:
Mine started slow with a few small dots/splatters. I wiped clean and continued flying a bit. After a few flights it puked quite a bit out and the shop said they had to pull them and send them in. It had been several years since overhaul so none of the prop shops were willing to just re-seal so I did the full overhaul on them. They came back zero time looking brand new. The seal's were essentially dry rotting from time/exposure. How many years are on the prop? Mine had about 400 hours but close to 15 years as the previous owner wasn't flying enough. They are McCauly's. If you don't have too many years on them they will just re-seal for much cheaper than overhaul.
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I would have to look at the log for when the overhaul was done. Have had the plane about 4 years. Prop was about 175 hrs when it was purchased. So likely about 6 years since overhaul was done.

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Tom-D said:
Send that prop to the prop shop for a re-seal. Grease coming out of the blade root, means someone has over greased it and have blown the seal.
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:yeahthat:

It can also be due to not greasing the hubs and flying the plane infrequently. The seals dry out and then grease starts tracking from the hub out along the blade. Can get much worse if the hub is subsequently greased properly.
 
GRG55 said:
It can also be due to not greasing the hubs and flying the plane infrequently. The seals dry out.
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Either way??

Now he says that it may be red oil??
If it is a "red oil prop" it is cracked.
Get it fixed !

There are things that even some prop shops can't do.
 
If it were the dyed red stuff from a cracked hub, there'd be no mistaking the color. It ain't "brownish". Probably blown seals, and probably from somebody not removing the grease zirk opposite the one being greased. Anyway, it's not going to get better on it's own. A little streaking isn't going to result in blades flying off, but don't let it go. At 6 years, most shops are going to want to overhaul. Ask for an inspect and repair as necessary, might save you some bucks.

Sensenich in Lancaster is good too.
 
Hartzell? Tell the clown who does your maintenance next time to follow the effing instructions. You remove one of the zerk fittings before putting grease in the other. You want the excess to come out the grease hole not be squeezed out the blades.
 
flyingron said:
Hartzell? Tell the clown who does your maintenance next time to follow the effing instructions. You remove one of the zerk fittings before putting grease in the other. You want the excess to come out the grease hole not be squeezed out the blades.
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Yes it is a Hartzell. I am already switching maintenance shops from the one who did the last annual. It would not surprise me if they did it wrong. Since the service in April I have had a complete battery failure. The service cone that covers the stabilator assembly was over tightened to the point it was almost rubbing the rudder. And I have found at least two sizable chips in the fiberglass of the cowling I know we're not there before. Needless to say, I was already upset with them. Just careless stuff and thing that should not have been missed.

No the fluid is not bright red fluid, is is best described as clean engine oil colored. I know bright fluid from when the front actuator went bad.

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If the grease is coming out of the "zerts" (grease fittings for adding grease), just clean it up and dont add more grease. Its just "burping". At least thats the way my aluminum Hartzel constant speed on a Lycoming 180 Husky is.
 
Zerk, not zert. Grease won't come out them unless they are defective (they're effectively one-way in). However, the way you grease a hartzell hub is to remove one of the zerks and pump grease in the other until grease appears in the hole you for the one you removed. This is distinct from the usual automotive way of greasing things where you just put the gun on to every zerk you can find and pump grease in until it comes out somewhere.
 
Grease came out of my zerks. Hard to believe but true. I saw evidence of it, the Hartzell rebuild shop TOLD me that and it is a KNOWN malfunction.

However, I don't blame you if you don't believe me because it is somewhat unexplainable as to why. Of course there IS an explanation. We just don't know what it is. It may just be the grease is coming around the threads and not out the center or something like that. Or perhaps the ball in the zerk gets some dirt in it. Some kind of malfunction.

If grease is leaking from a zerk, the zerk should be replaced and correctly installed and tightened.
 
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flyingron said:
Zerk, not zert. Grease won't come out them unless they are defective (they're effectively one-way in). However, the way you grease a hartzell hub is to remove one of the zerks and pump grease in the other until grease appears in the hole you for the one you removed. This is distinct from the usual automotive way of greasing things where you just put the gun on to every zerk you can find and pump grease in until it comes out somewhere.
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Hartzell Owner's Manual 115N states to remove one zerk (lubrication fitting) and clear any blockages or hardened grease with safety wire. "Pump a maximum of 1 fl. oz. (30 ml) grease into the lubrication fitting, OR until grease emerges from the hole where the lubrication fitting or lubrication hole plug was removed, WHICHEVER OCCURS FIRST." If you pump more than 1oz of grease you can blow out a blade o-ring or fill the center cavity of the hub with grease which can turn the prop into a fixed pitch.

The blade o-rings generally have a life around 7-8 years before they start to deteriorate and cause a leak. The grease in a Hartzell is AeroShell 6 which is a tan color. You should not see any red oil leaking from a Hartzell prop unless it has the oil fill conversion using HC-SB-61-269 as an AMOC to AD 2009-22-03 or AD 2006-18-15. You would know if your prop had this conversion done.

Check all zerks to ensure the ball is properly seated. Sometimes the ball will not seat properly which will expel any grease in the hub. If you find a faulty zerk replace it.
 
Thank you for posting factual information. We had a prop shop within a minute's walk of our shop and when I had a question they were always eager to help. Their take on Hartzell props was that it was an exercise in futility to lubricate them at annual unless there was grease leaking by the seals. They said if there was no leakage leave sleeping dogs lie.

I do not have a prop repairman's certificate. They do so I will take their word as gospel.
 
Norman said:
Thank you for posting factual information. We had a prop shop within a minute's walk of our shop and when I had a question they were always eager to help. Their take on Hartzell props was that it was an exercise in futility to lubricate them at annual unless there was grease leaking by the seals. They said if there was no leakage leave sleeping dogs lie.

I do not have a prop repairman's certificate. They do so I will take their word as gospel.
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Norm,
The main job of the grease is a corrosion preventative so I would still recommend lubricating the propeller at annual. AeroShell 6 has a tendency to separate into an oily base which often times appears as a grease/oil leak.
 
mvanbv00 said:
Norm,
The main job of the grease is a corrosion preventative so I would still recommend lubricating the propeller at annual. AeroShell 6 has a tendency to separate into an oily base which often times appears as a grease/oil leak.
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The description of AeroShell 6 having an oily base seems accurate concerning what I am seeing. The material I am seeing is definitely on the oil side of the spectrum.

Would the leakage pattern look different between a bad Zerk vs. a bad O-ring?

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If its oil, its not from a Zerk.
If they are leaking from the Zerk it is grease and there is usually grease on the zerk. If its not leaking grease anywhere else, it must be the zerk? Not sure you can say that either. Process of elimination. Zerks are inexpensive, if suspect, replace. If it stops, must have been the zerk.
 
Zerk fittings contain a tiny spring that forces the check ball to seal. Springs weaken, they can break, they can rust, and can make the grease orangish.

I have seen seals damaged by too high of pressure lubrication (pressure pots utilizing shop air) when a hand pump grease gun should have been used. Be careful out there.
 
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drotto said:
The description of AeroShell 6 having an oily base seems accurate concerning what I am seeing. The material I am seeing is definitely on the oil side of the spectrum.

Would the leakage pattern look different between a bad Zerk vs. a bad O-ring?

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The grease leak of a bad zerk and a bad blade seal could look almost identical. With a blade seal leak it will most likely leak straight onto the blade and you will see streaks on the blade. With a zerk leak you may see the grease accumulate on the inside of the spinner dome and eventually streak down the blade.

As GlennAB1 said the zerk springs can weaken and may need replacement.
 
GlennAB1 said:
Zerk fittings contain a tiny spring that forces the check ball to seal. Springs weaken, they can break, they can rust, and can make the grease orangish.

I have seen seals damaged by too high of pressure lubrication (pressure pots utilizing shop air) when a hand pump grease gun should have been used. Be careful out there.
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You can put a lot of pressure into the fitting with just a hand gun if you don't know what you're doing as well.
 
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