CS Prop on 182 misting light amount of oil on hood and windshield

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JasonM

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I own a T182T and the CS Prop is leaking a little amount of oil somewhere near where the blades rotate. The only visible proof is a light splatter on each propeller within the first 12 inches then mostly visible on the hood and windshield of the airplane. I had my shop take a look at it a couple times and I am told to just keep an eye on it. It also doesn't seem to be getting any worse, just consistently happening. Anyone experience this? What would fix the problem?
 
How many years and hours since overhaul, IRAN or reseal?
 
New prop seals would fix it. Had it happen to me on a '79 Piper Dakota back in '81. It eventually let go and spewed all the engine oil out when someone else was flying it.
 
Prop seal. There's a rubber gasket in there and if it doesn't have a good seal, it'll spray oil. Mine was split in half due to faulty maintenance and it went all over my windscreen. You don't want that thing to fail like that.
 
Could be anything from a o-ring to a new crankshaft ;)

Grease is no major problem, oil is.
 
RV10flyer said:
How many years and hours since overhaul, IRAN or reseal?
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New in 2004 - edit: 800 hours

LDJones said:
New prop seals would fix it. Had it happen to me on a '79 Piper Dakota back in '81. It eventually let go and spewed all the engine oil out when someone else was flying it.
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Was it a big procedure? $$$, Sounds more urgent than what my shop is telling me.

Velocity173 said:
Prop seal. There's a rubber gasket in there and if it doesn't have a good seal, it'll spray oil. Mine was split in half due to faulty maintenance and it went all over my windscreen. You don't want that thing to fail like that.
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Definitely, do not want it to get any worse.


weilke said:
Could be anything from a o-ring to a new crankshaft ;)

Grease is no major problem, oil is.
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I've had a few leaky spots and this is the final one. Replaced front engine seal, oil return lines, now this. hoping its not too costly to fix.
 
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prop reseal is about an AMU - not horrible as things go - reseal is better than spewing all oil out - little bit of grease though isn't big deal, can leave until A&P sez "that's too much"
 
Clark1961 said:
prop reseal is about an AMU - not horrible as things go - reseal is better than spewing all oil out - little bit of grease though isn't big deal, can leave until A&P sez "that's too much"
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AMU? I have been letting it go for the past 2 months, but having to wipe the airplane down after every flight due to the oil has me determined to get this resolved.
 
Any idea on the amount of time to change out the prop seal?

Anyone have a link to a diagram? I'd like to see what and where this seal is.

Thanks..
 
JasonM said:
I've had a few leaky spots and this is the final one. Replaced front engine seal, oil return lines, now this. hoping its not too costly to fix.
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Yes, 99% of the time it is a failed gasket or some other 'easy' fix (nothing on planes is 'easy'). Once in a while, oil-misting is the first sign of a through-crack in the crankshaft flange. The picture below happens to be from the Malibu that landed prop-less in Aspen, but there are others out there. The area with the 'o' is the part that took a long time to slowly crack through (indicated by those 'rings' through the crack surface). Everything to the right of the dashed line that looks coarse is the over-stress crack when the prop finally came off. Some people with oil-misting have found a crack at the fillet radius where the shaft turns into the flange. So while the prop is off clean off any grime and have a very close look at that radius before you blame it on the gasket.
 

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weilke said:
Yes, 99% of the time it is a failed gasket or some other 'easy' fix (nothing on planes is 'easy'). Once in a while, oil-misting is the first sign of a through-crack in the crankshaft flange. The picture below happens to be from the Malibu that landed prop-less in Aspen, but there are others out there. The area with the 'o' is the part that took a long time to slowly crack through (indicated by those 'rings' through the crack surface). Everything to the right of the dashed line that looks coarse is the over-stress crack when the prop finally came off. Some people with oil-misting have found a crack at the fillet radius where the shaft turns into the flange. So while the prop is off clean off any grime and have a very close look at that radius before you blame it on the gasket.
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Ok, thanks. I will point that out as a possibility.
 
JasonM said:
Any idea on the amount of time to change out the prop seal?

Anyone have a link to a diagram? I'd like to see what and where this seal is.

Thanks..
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reseal in a prop shop is a day - back log around here is a month, YMWV
 
I had my 421 props resealed a couple years ago, I think it was $2K each, but I don't recall the exact amount. They were 200-250 since new, but they were 10 years old and they were slinging a little grease, not too much, but enough I didn't want one of them to take a dump at a bad time. :D
 
Avoidance is not the answer,have the prop reseated before the problem gets worse. The misting is a warning sign.
 
Mine is the same model age and hours. I got it at about 500 hours and needed to get some experience in it. My instructor said to pull aggressively on the prop at the run up. After doing it like that, I noticed some red mist on the cowl and a little on the windscreen. I stopped doing that aggressively and have operated the prop control more slowly. Ever since, I have not seen any mist or spray.
 
Definitely a prop seal. Had same problem once on my Arrow. Typically the prop is sent off to a specialty shop for the work, then sent back to your mechanic to reinstall.
 
Datadriver said:
Definitely a prop seal. Had same problem once on my Arrow. Typically the prop is sent off to a specialty shop for the work, then sent back to your mechanic to reinstall.
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So this isn't something an average mechanic can do?
 
skidoo said:
Mine is the same model age and hours. I got it at about 500 hours and needed to get some experience in it. My instructor said to pull aggressively on the prop at the run up. After doing it like that, I noticed some red mist on the cowl and a little on the windscreen. I stopped doing that aggressively and have operated the prop control more slowly. Ever since, I have not seen any mist or spray.
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I was told the same thing on day 1. I did a deep cycle and the CFI said "whoa, not so much." I have been very gentle and slow on that part during the runup and return to max rpm as soon as I see the slightest sign of oil pressure drop, so I know that is not my problem.

btw, I just got a pm by another person on here saying how doing just this fixed his from leaking.
 
So......what will you do? Wait until it develops into a real problem for big dough or send it to a prop shop for a look see and proper maintence?
 
Jimmy cooper said:
So......what will you do? Wait until it develops into a real problem for big dough or send it to a prop shop for a look see and proper maintence?
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Get it fixed of course. My Mechanic has had a different outlook, but I would rather not take that risk which is why I am inquiring abroad such as on this forum. My gut was telling me that it was not acceptable to just wait and see any longer.
 
I had to have the front engine seal replaced a few months ago do to oil being spewed out everywhere. The shop that did this said it was the "prop seal" but the real term for it is the "front engine seal". Knowing where that oil leaks which was all over inside the engine compartment, fan belt, etc. I have to assume that the "prop seal" is actually something different than the "front engine seal". That fix was very expensive but a normal shop did the work. Is the "prop seal" more complicated?
 
I'm not familiar with the prop on a 182. If it is like the prop on the 'kota then the blade angle is set by oil pressure below a piston which acts against a spring. The spring pushes blade angle to fine while oil pressure, controlled by the governor, pushes the blade angle coarse. The piston seal is a potential leak site.

If there is a prop shop in the neighborhood then give them a call. They probably can show you how your prop works and which seals do what. There are grease seals which also need to be replaced periodically or when damaged by an A&P injecting excessive grease.
 
There are a couple of places this can come from.
1 Leaking past the piston and sloshing around in the hub.
2 The seal between the prop hub and the crank.
3 the front engine seal.

It shouldn't come from the blade roots. If it does, there is oil in the hub where it shouldn't be. There is however grease in that area which is what you can spit out with aggressive rpm changes, either during runup or when going to high rpm anf the plane 'pushing' the engine.
,
 
I don't think you need to send it off to a prop shop. I had just gotten mine back from overhaul and my A&P forced the prop on without taking off the lower cowling. When he did, he split the rubber o ring in there. It's like a $2 piece but it's important in maintaining a good seal. Just have your mech take the prop off and try a new o ring in there. Could be the seal between the shaft and the engine but I'd be willing to bet it's the prop hub seal. Doesn't sound like prop grease either.i
 
JasonM said:
I had to have the front engine seal replaced a few months ago do to oil being spewed out everywhere. The shop that did this said it was the "prop seal" but the real term for it is the "front engine seal". Knowing where that oil leaks which was all over inside the engine compartment, fan belt, etc. I have to assume that the "prop seal" is actually something different than the "front engine seal". That fix was very expensive but a normal shop did the work. Is the "prop seal" more complicated?
Click to expand...

Prop disassembly and repairs must be completed by a prop shop. A&P's remove, ship and reinstall after the prop shop does their thing.



Everything aft of the prop is engine work. It sounds like you had the crankcase nose seal replaced in the past. Well replacing the crankshaft to prop o-ring is slightly easier and can be done by any A&P.


Crankshaft should be carefully inspected ANYTIME the prop is removed. If cracked, overhaul time.
 
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Clark1961 said:
I'm not familiar with the prop on a 182. If it is like the prop on the 'kota then the blade angle is set by oil pressure below a piston which acts against a spring. The spring pushes blade angle to fine while oil pressure, controlled by the governor, pushes the blade angle coarse. The piston seal is a potential leak site.

If there is a prop shop in the neighborhood then give them a call. They probably can show you how your prop works and which seals do what. There are grease seals which also need to be replaced periodically or when damaged by an A&P injecting excessive grease.
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I don't know of any prop shops in the area. I just flew the plane to a service center and dropped it off. crossing my fingers that I see her again soon and don't have her stuck away from home for a month.

weilke said:
There are a couple of places this can come from.
1 Leaking past the piston and sloshing around in the hub.
2 The seal between the prop hub and the crank.
3 the front engine seal.

It shouldn't come from the blade roots. If it does, there is oil in the hub where it shouldn't be. There is however grease in that area which is what you can spit out with aggressive rpm changes, either during runup or when going to high rpm anf the plane 'pushing' the engine.
,
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Would the grease look like oil spray on a hood/windshield? it definitely happening from working the prop. If I flew without adjusting the prop, no oil would spew out, so you may be on to something with the "going to high rpm". I normally cruise at 2200 RPM then on approach for back to 2400 RPM.

Velocity173 said:
I don't think you need to send it off to a prop shop. I had just gotten mine back from overhaul and my A&P forced the prop on without taking off the lower cowling. When he did, he split the rubber o ring in there. It's like a $2 piece but it's important in maintaining a good seal. Just have your mech take the prop off and try a new o ring in there. Could be the seal between the shaft and the engine but I'd be willing to bet it's the prop hub seal. Doesn't sound like prop grease either.i
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I hope that's what I hear. I am crossing my fingers.

BillTIZ said:
AMU, Aviation Monetary Unit,

1AMU = $1,000 USD
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ahh. i've heard others similar, never AMU till now. thanks. :D

bnt83 said:
Prop disassembly and repairs must be completed by a prop shop. A&P's remove, ship and reinstall after the prop shop does their thing.



Everything aft of the prop is engine work. It sounds like you had the crankcase nose seal replaced in the past. Well replacing the crankshaft to prop o-ring is slightly easier and can be done by any A&P.


Crankshaft should be carefully inspected ANYTIME the prop is removed. If cracked, overhaul time.
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I wonder if it would make sense to get it overhauled right now. Sounds like it could be expensive either way.
 
Not sure you are aware, but it looks like the OEM recommended calendar TBO time is 60 months for most McCauley props.
 
JasonM said:
Would the grease look like oil spray on a hood/windshield? it definitely happening from working the prop. If I flew without adjusting the prop, no oil would spew out, so you may be on to something with the "going to high rpm". I normally cruise at 2200 RPM then on approach for back to 2400 RPM.
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Well, it's grease, it is thicker. More of a feel thing than seeing the difference. After last years annual, our Hartzell prop was slinging grease for weeks. Usually at the end of the flight if someone was a bit agressive in advancing the prop control the window fogged over. I assume the blade flexing back and forth allowed some grease to escape (the prop gets serviced with grease during the annual). IA said it's ok 'they do that' and 'it'll go away'. He was right, it went away after a while.
Fast forward to this annual. Prop went out for overhaul. 3 blades condemmed, hub condemmed, hydraulic cylinder condemmed :) . We now have a nice new prop.
Hartzells are apparently known for slinging grease. I dont even know whether McCauleys have the same kind of grease pack in the hub.

If it is truly oil, the first place to look would be your replaced front engine seal. There are a couple of different ways to put the seal in, not all of them lead to the same result.
 
coloradobluesky said:
Props have GREASE, engines have OIL. Which is it, grease or oil?
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Not all props have grease. Some of the older McCauley CS props have a red oil in them. I have my doubts that the OP's airplane has one of these props however.

The oil lubed McCauleys seem to have a tendency to leak occasionally, cleaning up the mess and flying the plane usually seals them back up.
 
There are 3 different seals in that area that everyone is talking about. One is the oring that goes on the front of the crankshaft and seals the prop to the crank flange. The next is the crank seal that goes around the front of the crank and seals the outside of the crank to the engine case. Both of these are easily replaced by your local A&P.

The third are the actual seals inside the prop. In this case it sounds like it is those seals, which are causing oil or grease to migrate up the blades. Only an approved prop repair shop can disassemble and replace these seals. And the last time I sent a prop out from a 182, it was about 1200 for a reseal.

Good luck, these never get better with time!
 
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Jetwrench said:
There are 3 different seals in that area that everyone is talking about. One is the oring that goes on the front of the crankshaft and seals the prop to the crank flange. The next is the crank seal that goes around the front of the crank and seals the outside of the crank to the engine case. Both of these are easily replaced by your local A&P.

The third are the actual seals inside the prop. In this case it sounds like it is those seals, which are causing oil or grease to migrate up the blades. Only an approved prop repair shop can disassemble and replace these seals. And the last time I sent a prop out from a 182, it was about 1200 for a reseal.

Good luck, these never get better with time!
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They never get better with time, just get more expensive or fail, maybe on takeoff. Usually a poor mechanic never gets better with time either.
 
Jetwrench said:
There are 3 different seals in that area that everyone is talking about. One is the oring that goes on the front of the crankshaft and seals the prop to the crank flange. The next is the crank seal that goes around the front of the crank and seals the outside of the crank to the engine case. Both of these are easily replaced by your local A&P.

The third are the actual seals inside the prop. In this case it sounds like it is those seals, which are causing oil or grease to migrate up the blades. Only an approved prop repair shop can disassemble and replace these seals. And the last time I sent a prop out from a 182, it was about 1200 for a reseal.

Good luck, these never get better with time!
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Thanks. I have the airplane in good hands right now. Just waiting on them to find time to look at it. I wonder if it would make more sense to just get a fresh prop overhaul. $1200 compared to ???
 
We had a year where we would find a small blob of oil and/or grease on top of the cowl after a long flight. Discussion with the mechanics (multiple) pointed out the McCauley has a service bulletin recommending "deep cycling" the prop during run-up for a period of time and monitoring the behavior.

We did, and no more blobs.

We also found that on the O-470 there's a metal plate that's built to retain that rubber seal at the front of the engine. Our specific model year it wasn't required, but most 182s have it.

After discussion with the AI regarding "What happens if the seal fails suddenly?" and learning the reason it's required on most O-470 engines... e.g., the seal can blue out and dump all oil pressure and most if your oil at once... We added it.

Just thoughts from the world of 182 maintenance here... Your mileage may vary.
 
So what did you find? How was the problem fixed? And of course, the cost.

JasonM said:
Thanks. I have the airplane in good hands right now. Just waiting on them to find time to look at it. I wonder if it would make more sense to just get a fresh prop overhaul. $1200 compared to ???
Click to expand...
 
coloradobluesky said:
Props have GREASE, engines have OIL. Which is it, grease or oil?
Click to expand...

All constant speed props, except the electrics have engine oil in them, and yes, some have grease fittings too. the newer ones have no grease in them.
 
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