Pics of my prop hubs and gear oil. First time questions.

[MalibuMike]

Last year I had my props serviced. They were balance and any blemishes were repaired at a reputable shop. They did note on the invoice that due to internal corrosion, they could not be re hubbed.
I recently took the props off to change the gear oil and add grease to the prop shaft. I did find some light white colored corrosion and some of the splines in the hub showed some loss of material. Can anyone tell me what condition these are in? I dont know what is normal or if a shop was trying to sell me a new pair of ss props.

Also, I drained my gear oil. After about twenty minutes, when the very last bit was draining out, the green gear oil had some very slight streams of milky colored oil coming out .Keep in mind 99 percent of the oil that came out was a translucent green oil but a very small amount of this discolored stuff came out. Would that indicate a leak or does some moisture get in to the gear case naturally?

 

[Horigan]

Your prop hubs look fine. In addition to greasing the shaft, grease the inside of the hub where the splines are corroded.

You have a mild leak in your drive. Water does not naturally get in there. You need to pressure/vacuum test it go confirm the leak location.

 

[BRICH1260]

I`d take a brass wire brush or something similar and get down inside the hub and clean out the lands and grooves. Then liberally coat with prop grease the cleaned areas and the prop shaft. Seems like you have a small leak somewhere, you can probably make it through this summer of boating, but it need attention soon. Maybe something as simple as a bad O ring or could be a prop shaft seal.

 

[dubs283]

Props look fine to me, just use additional grease where the corrosion is located. May pull props during the season to inspect/regrease if it worries you.

Gear oil looks normal, if the level before draining was good I would not recommend pressure testing the drive, you do not have a leak. If the oil were milky you'd know it

 

[Horigan]

Looking at the pics again, I agree with @dubs283. The gear oil looks normal. The oil is just a bit dirty.

 

[MalibuMike]

I`d take a brass wire brush or something similar and get down inside the hub and clean out the lands and grooves. Then liberally coat with prop grease the cleaned areas and the prop shaft. Seems like you have a small leak somewhere, you can probably make it through this summer of boating, but it need attention soon. Maybe something as simple as a bad O ring or could be a prop shaft seal.

Thank you. I did take a wire brush and cleaned everything really good. Then a fair amount of grease. I think Ill pull the props every 4 months for grease and inspect a small amount of gear oil every few months.

 

[dingbat]

Don’t like the looks of the galvanic corrosion on the prop?
Will live another year but you need to find out why they are corroded so bad.

Keep in a slip?
Zincs good?
Your LU ground strap still connected?

 

[MalibuMike]

Don’t like the looks of the galvanic corrosion on the prop?
Will live another year but you need to find out why they are corroded so bad.

Keep in a slip?
Zincs good?
Your LU ground strap still connected?

I keep my boat in dry storage on a trailer. 2 previous owners ago, the boat was in Florida. When I got it, there were small tropical looking barnacles in hard to reach places on the outdrive so I believe it was left in the water at some point. The hubs could be original to 97!

 

[dingbat]

I keep my boat in dry storage on a trailer. 2 previous owners ago, the boat was in Florida. When I got it, there were small tropical looking barnacles in hard to reach places on the outdrive so I believe it was left in the water at some point.

Could be but you said the prop was reconditioned last year.

The white powder is galvanic corrosion. Salt or fresh?
Zinc or aluminum?

Test ohm reading between prop and anode. Should be less than one

 

[MalibuMike]

Could be but you said the prop was reconditioned last year.

The white powder is galvanic corrosion. Salt or fresh?
Zinc or aluminum?

Test ohm reading between prop and anode. Should be less than one

The prop was pulled off last year and I was charged $250 for each prop to "repair and balance". I have had the boat in salt water for a total of 13 days since then. All day trips, except for 2 overnight trips. Can galvanic corrosion happen on short trips?
A new VP zinc was placed on the outdrive. Are you asking if the hubs are Zinc or aluminum?

 

[dingbat]

Can galvanic corrosion happen on short trips?

Doesn't need to be in the water. The moisture trapped in the splines is more than enough to enable the process on dry land.

A new VP zinc was placed on the outdrive.

“New” means nothing……zincs are not fond of being taken in and out of the water. Tend to oxide over when exposed to air.
I changed over to aluminum a while back.

Check ohm between prop and zinc. That will tell you in a hurry if you have a problem