No good deed goes unpunished...

During the last annual on N209RV (RV-9A) I decided that I should grease the prop hub. I've flown at least three times since then with no indication of a problem. Yesterday's flight however was different. The preflight inspection showed no problems. Runup and takeoff was fine but on climb out I started to see the windscreen being covered with something. It was not streking off and in just a minute or two the passenger side was hard to see through. I made a quick 180 and put in a slip to get back on the ground since I didn't know what was going on or how long before the left side was covered too. Back on the ground I removed the spinner and found that one of the grease fittings, a zerk, had failed. Grease had flung out of it. Upon removal it was apparent the check ball was not sealing. I'm assuming that greasing the hub had forced some dirt into it. Now to get that replaced and grease it again. All's well that ends well.

Good decision

Your post could also read: Good decision making results in great ending!
Good job getting back safely.

Good job in getting it down safely.

This maybe a timely post for me as I am going thru my annual and just greased the hub. Some thing to watch for, I suppose.

Not the first

The same thing happened to a friend on his first flight! So check those little balls when new and each time it is greased.

When greasing the prop (CS)...

You need to remove the lower two zerks fitting and then pump grease into the upper two fittings. Then reinstall the lower zerks fittings.
If you grease gun is clean there should be no chance to get contaminate in any of the fittings.

Kent

At one point I got so tired of leaky zerks I welded the ends closed. Problem solved. When I regreased the prop I just swapped a temporary zerk in.

kentb said:

You need to remove the lower two zerks fitting and then pump grease into the upper two fittings. Then reinstall the lower zerks fittings.
If you grease gun is clean there should be no chance to get contaminate in any of the fittings.

Kent

Click to expand...

I am not sure if this is correct. The way I understand it for a tractor type, you will pull the aft zerk and pump the front zerk (up and down) and for the pusher type is reverse.

Hartzel will tell you they have never serviced a prop for not having enough grease. They routinely service props for being over greased. Just someting to keep in mind.

rocketbob said:

At one point I got so tired of leaky zerks I welded the ends closed. Problem solved. When I regreased the prop I just swapped a temporary zerk in.

Click to expand...

Great idea!

I never had a problem with leaky zerks, but its a trip to the autoparts store and an appointment with mr oxy-acetylene before the next lube job!

Frank

Yep, pull the aft zerk.

I talked with the local A&P before I started this little operation and he had me pull the aft zerk and pump the front zerk. Plus the grease gun and grease were both new so I don't know where the dirt (or whatever) came from.

C/S grease leaking

C/S grease leaking. This is not critical, although good job landing and pulling the spinner. That is the right thing to do if unknown reason. Compliments to you for good decision making. New Zerk's now. They do make Zerk caps, although I don't know if this application would just throw them off with centrifugal force?

Cleanliness.

Our zerks on the Air Tracor's big Hartzell have rubber caps that we safety wire, so they don't fall off. We grease every one hundred hours....three times a year, usually.

We also have a ziplok baggie slipped over the grease gun nipple, because it's a dirt magnet...leading to the stuck-ball problem.

I also have a dedicated funnel for adding oil. The open ends have a twisted-up paper towel inserted to keep dirt out and then the whole shebang is put into a Piggly-Wiggly plastic bag and put in a closet, to keep dirt out.

Cleanliness is next to G....well, you get the idea.

Best,