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F--- up of the day, week, maybe year!

kaweeka

Well Known Member
I removed my propeller last week to change the front flywheel seal. The prop is a constant speed Hartzel. After removal, close inspection showed a dry seal. No need to change it. There is a small leak from the seam of the case. Got it back together, safety wired on then started it up for a ground check. Typical airport project... people cone and go during the task, wanting to know all about what you're doing. All went well going back together, I thought, until I cycled the prop and there was no RPM change. Oil pressure good. Then the the cold realization that I screwed up! After removing the propeller, I found what I thought. I had left a paper towel in the hub. There it was, sitting right there. I removed it and put the prop back on. Ground run up and..... still no RPM change. So, obviously, not all of the paper towel was in sight. So, I'm looking for a little guidance here. I'll sent the prop to Stockton Propeller for inspection. What about the oil line or the prop governor? Is there a need to take that off and have it inspected as well? This is an expensive mistake. Distractions can certainly be costly, not to mention deadly. How embarrassing!
 
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it can take much longer than usual for the prop to cycle, the first time, after it's been off. how long did you wait when cycling it?
 
Inspect the residue

Still got the offending paper towel?

Carefully unfold and examine if you can; you'll know you got it all...
 
Still got the offending paper towel?

Carefully unfold and examine if you can; you'll know you got it all...

I went back to the airport and looked. It's missing about 25% of the paper towel and I can see some of it way down in the hub. Couldn't get much out.

RATS!!!!!
 
Wind your watch...

Now that you have a better understanding, you might pause further disassembly, call governor manufacturer (Hartzell, Aero Technologies...) on Monday.

Thank you for posting this.
I learned from your experience, maybe others will as well.
 
David,

You are part of a surgical team.

"As part of the overall tracking of items in the operating room (Hangar), each facility (Experimental Pilot working on their aircraft) should have a policy for surgical counts (Tool Inventory) that specifies when they should be performed and by whom, what items (Paper towels) should be counted and how counts (including incorrect counts) should be documented. A specific procedure for counting should be established to ensure that the protocols are standardized and familiar to operating room personnel."

You are an expert my friend. Endoscope?

This probably wouldn't have happened if you were still parking it on the south side. Not many Lookie Lou's in these parts.

Wish you the best.
 
I went back to the airport and looked. It's missing about 25% of the paper towel and I can see some of it way down in the hub. Couldn't get much out.

RATS!!!!!

The oil (and towel) is trapped in the crank chamber. The collar feeds oil through the crank into the chamber, and it leaks back out to the collar. Carefully dig in the crank cavity and get the remains of that towel. I would prepare to pressurize the oil feed to the collar with external oil to push any towel in the cross tube back in the crank cavity. Call a reputable engine builder and ask what they recommend. And . . if pressurizing will push the towel back into the cross tube (from the collar volume). I think it will but some could remain and get into the bearing. That could starve oil pressure there. Not good if that happens.

Good luck. I will now only use cotton towels to prevent this.
 
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I attempted to get out what I could with a very small hook but it wasn't much. I'll call Stockton Propeller Monday and humbly admit my mistake. After a good laugh, they'll pick it up and get it back to working order. I will also ask about my prop governor. If they think it should go in as well, so be it. Thanks for the replies everyone. Lesson learned!
 
Pull your governor. There is usually a small screen imbedded in the gasket to keep foreign matter from getting into the governor.

Good luck
 
The oil (and towel) is trapped in the crank chamber. The collar feeds oil through the crank into the chamber, and it leaks back out to the collar. Carefully dig in the crank cavity and get the remains of that towel. I would prepare to pressurize the oil feed to the collar with external oil to push any towel in the cross tube back in the crank cavity. Call a reputable engine builder and ask what they recommend. And . . if pressurizing will push the towel back into the cross tube (from the collar volume). I think it will but some could remain and get into the bearing. That could starve oil pressure there. Not good if that happens.

Good luck. I will now only use cotton towels to prevent this.

Thanks for that detail. There wasn't anything in the crank, just fragments deep in the prop hub. That, at least may be fractionally "good" news?
 
This is a good lesson on why we should only use cloth rags when stuffing an opening in an engine. much harder for a cloth rag to be made into pieces. paper towels tear up to easy.

bob burns
RV-4 N82RB
 
This is a good lesson on why we should only use cloth rags when stuffing an opening in an engine. much harder for a cloth rag to be made into pieces. paper towels tear up to easy.

bob burns
RV-4 N82RB

Yep, a red shop rag would have been much more noticeable than a blue paper towel but ultimately, it's a failure of attention on my part. I'll post what the prop shop says after I speak with them today.
 
Several years ago a buddy asked me to look at his Cardinal to see if I could determine why his oil temp was very high after having a recent annual. A scat tube runs from the back baffling to the oil cooler after making a 90 degree bend. I found a shop rag on top of the oil cooler, under the bellows that feeds the cooler. Apparently, a mechanic had left a rag on top of the engine, which got forced thru the scat tube, blocking the cooler. The shop denied everything, of course.

Bruce Estes
RV 6
Cardinal177b
 
Spoke with Stockton Propeller this morning. After I owned up to my blunder, he graciously told me this didn't even crack the top ten :) . He explained this was more common than you would think and all he needs to do is remove the cap and clean out the fragments of paper. He feels very strongly that nothing went back to the governor. He will fix it today. Randy Thorne was kind enough to take it to the shop.
 
So, Dave needs a new ?handle?. This forum is perfect for soliciting suggestions. I?ll start off with ?Ragdoll?. Fire away and I will make sure everyone at our airport and EAA is aware of Dave?s new handle. Dave, you are allowed to participate, if you dare.
Bruce Estes
 
So, Dave needs a new ?handle?. This forum is perfect for soliciting suggestions. I?ll start off with ?Ragdoll?. Fire away and I will make sure everyone at our airport and EAA is aware of Dave?s new handle. Dave, you are allowed to participate, if you dare.
Bruce Estes

DOH!!! I don't dare :)
 
Spoke with Stockton Propeller this morning. After I owned up to my blunder, he graciously told me this didn't even crack the top ten :) . He explained this was more common than you would think and all he needs to do is remove the cap and clean out the fragments of paper. He feels very strongly that nothing went back to the governor. He will fix it today. Randy Thorne was kind enough to take it to the shop.

Near miss - - good news!! The debris would have to get through the front crank bearing, into the sump in order to get back in the governor screen. You are good to go!
 
So, Dave needs a new ?handle?. This forum is perfect for soliciting suggestions. I?ll start off with ?Ragdoll?. Fire away and I will make sure everyone at our airport and EAA is aware of Dave?s new handle. Dave, you are allowed to participate, if you dare.
Bruce Estes

I'm thinking "3M". Then when someone asks "Why do they call you that?" The eyes roll and the story spills out.... ;-)

Seriously, I think we are all hoping for a good outcome from this little faux pas. :cool:
-Marc
 
Rag doll and 3M are both great

Brawny or Bounty may work as well, but call signs should never be too cool.

Just looked in our pantry and we currently have "Sparkle" and Kirkland (Costco) brand. I am partial to Sparkle. :)
 
Nods to all the creativity going on here, the prop shop just called. The piece of paper towel was completely intact and fairly easy to remove. They thanked me for starting their week out with a laugh. Right now, we all need one so I'm happy to oblige. Thanks all for your input and thoughts.
Best wishes,
David
 
Nice! Good start to a Monday.

Ok, One more name for ya- "Towlie" from Southpark. He too likes to get "high", but of a different sort. :)

41e0d1c13f52ac031320109153ede52a.jpg
 
Just to close out this thread "The Towlie" would like to let y'all know the prop went on (sans towel) without incident. Run up was back to normal and all operational checks are OK. Ready to fly. One of the guys at LHM gave me some great advice. He only uses yellow shop towels so he is sure to notice them. I like that idea. I'll never turn down free knowledge.

Have a safe and healthy 4th weekend,
David "Towlie" Goldfarb
 
Next thing coming............ Shop towels emblazoned with "REMOVE BEFORE FLIGHT!"
 
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