Oil on windshield and cowl air inlets

[N601RX]

Pump the grease gun very slowly so the grease has time to disperse throughout the hub instead building up localized pressure and pushing the seals out. 

[Shadrach]

Pump the grease gun very slowly so the grease has time to disperse throughout the hub instead building up localized pressure and pushing the seals out. 

It has zero to do with how fast you pump the grease and everything to do with the quantity of grease in the hub. Hartzell prop hubs only have a bearing seal on the outer part of the hub. there is no bearing seal to prevent said grease from filling the cavity/cylinder where the piston moves outward to coarsen the prop pitch. If that cavity gets filled or nearly filled, when the prop is cycled the piston will move forward and push all of that excess to the path of least resistance...the seals.

[takair]

In the old days, with steel hub props, you filled until it came out of the opposite removed zerk. Unfortunately this thinking carries on and may still be taught at A&P schools. I certainly learned to do it that way. The newer aluminum hub props don't tolerate this well. Even if the extra grease does not sling out it can lead to a slight out of balance. I made this mistake a few years ago on an annual, it was an expensive lesson learned. It is why the FAA requires up to date data when maintaining aircraft.

[N601RX]

It has zero to do with how fast you pump the grease and everything to do with the quantity of grease in the hub. Hartzell prop hubs only have a bearing seal on the outer part of the hub. there is no bearing seal to prevent said grease from filling the cavity/cylinder where the piston moves outward to coarsen the prop pitch. If that cavity gets filled or nearly filled, when the prop is cycled the piston will move forward and push all of that excess to the path of least resistance...the seals.

I've been told by well respected prop shops that If done slowly it will simply come out the open opposite hole from the grease fitting you are using.  It seems you have the direction the piston is pushed reversed.  If done fast a couple of pumps is to much.

[N201MKTurbo]

Dale's airplane is a 252. It doesn't have a Hartzell prop. There are no zerk fittings on his prop.

[N601RX]

What I posted above was referring to a Hartzell. To clarify I was not saying take a zerk out on opposite blades and pump until it came out the other. I was saying to take the zerk out on the same blade you are pumping grease into.

[Shadrach]

Dale's airplane is a 252. It doesn't have a Hartzell prop. There are no zerk fittings on his prop.

See Dale's post from earlier in the thread.

If definitely appeared to be oil not grease. I checked the back of the prop and there was no oil on the back of the prop. It is a Hartzell prop. I believe it was last serviced within the last year.

[Shadrach]

I've been told by well respected prop shops that If done slowly it will simply come out the open opposite hole from the grease fitting you are using. It seems you have the direction the piston is pushed reversed. If done fast a couple of pumps is to much.

You're absolutely correct about the direction of piston movement brain fart on my part... Still the slow method is not mentioned by Hartzell nor recommended by my prop guy. Likely because the old grease gets a bit pretty thick relative to the fresh. Maybe you can get away with it in the summer heat down south....

See below:

http://www.aviationpros.com/article/10226378/recip-technology-the-propeller-that-spinning-disc-attached-to-the-engine?page=2

Clearly Dale has another issue, I apologize for the hijack...