Rudder wear

I'm wondering how much my rudder can be worn out before it should be replaced. The boat seems to drive just fine but when I inspect the rudder it looks like it's corroded near the top on the front and sides. The corosion looks like little craters all over. The boat is an 1982 American Skier. I'll probably replace the rudder next summer but I just wanted peoples advice. I'll post some pics later tonight.

There is no corrosion on the prop only the rudder.

thanks gents,

-phil

sorry for the HUGE pictures.

Phospher, You haven't mentioned how old the boat is and if it has been in salt water. It looks like zincification to me. It is the process where the zinc in brass will eventually erode out of the base of copper. I have seen it in old brass marine hardware. Without the zinc, it becomes very brittle. It also appears that it has been aggravated by the prop wash / cavitation. Zinc in salt water will be eroded very quickly and the reason it is used as a sacraficial anode on metal hulls in salt waters.

Your gel coat picture is tough to tell if you will need to wet sand or not. Start with some HD compound and buff first and see what happens. I've seen some pretty bad gel just buffed out.

When you post pictures, post them from top to bottom by using the "enter key between the pictures. When yo don't, they end up left to right and that makes the post wide. You can go back in to your own post and edit it.

Oh, your rudder! I would take it to a prop shop and see if they can grind out most of the erosion but then keep a eye on it. Start looking for a new one because they will need to do a lot of grinding!

The boat is an 1982 American Skier. It has never been used in salt per the previous owner who lives in Wisconsin. There isn't any damage to the prop or drive shaft from what I can tell. The tranny is smooth as butter and there are no vibrations. The engine has 620hrs.

I'm sure this is the original rudder...

Just got in from a LONG day on the boat. 9:0AM until 11:00PM.

thanks,

Phos, I'm surprised that you aren't having any steering issues like pulling to the right or left. I would be a little hesitant to start filing or grinding that. I have read (but I certainly don't know for sure) that grinding rudders can cause pretty significant drivability issues when not done right. I think there are rudders out there that are "tunable" but I haven't had any experience with them nor know anybody that has really played with them. It's kinda like tuning the fin on a slalom ski. Can make the ski perform completely different with very little movement. I agree with Pete that I've never seen erosion like that before. I would get that replaced.

For you to do it, would be a couple hundred bucks I'm guessing maybe even less depending where you get the rudder from. If you're even the slightest bit mechanically inclined and have some pretty basic tools, you should be able to do that easy. For a shop to replace it I would think it would run into about 500-600 bucks or better.

actually, i just found this post:::




1. Get a six pack of beer and start drinking. What else matters?




2. Remove rear seat.
3. Remove rear panel.
4. Remove rear floor board (might require removal of doghouse.
5. Remove saftey wire at top of rudder post/tiller arm.
5a. Support rudder from below (do not let it drop).
6. Remove bolt from top of rudder post.
7. Loosen clamping bolt on tiller arm.
8. Lift tiller arm up off of rudder post.
9. Remove rudder from below. may require jacking boat off of trailer bunks so rudder clears prop gaurd, if so equiped.

If replacing/removing rudder port, simply remove nuts from bilge side (4 ea.) and work rudder out from below...it will be stuck with sealant. If PO used 3M 5200, you can cuss him now and go get the twelve pack....you will need it.
------------------------------------------------


I don't think I need to remove the port? just drop the rudder out right? curious to see how that seals in there and how to put it back in so that it doesn't leak.


-phil

so, i might as well post all my concerns on this thread....

i have been reading about crankcase pressure and dipsticks popping out. after being on the lake and then checking the oil afterwards my dipstick is always just popped out a tad bit. i've never seen any oil around the dipstick area so i don't think it's blowing oil. also, the oil always looks good and not milky. should i have concerns?

when i say it pops up, it pop's up about a quarter inch, if that.

it's a 351 commander.

ps: i'm already addicted to this site.

not sure about the pcv valve. i will have to check. where is that located? but i do have a breather piped to the flame arrestor.

maybe that's it....
hmm.

Pete what kinda beaver eats brass?The guy does not say where the damage occured, but if them beavers up there eat rudders and props, this redneck ain't gonna jump into that water again.
Down here we have alligators,cotton mouths and all kinda critters that will bite or suck your blood,we even have a little critter that will bite and crawl thru a tent mesh screen, the are called NO SEE UM'S,for real.
But we don't have nuttin' that will eat the balls off a brass monkey.......boat dr

Phospher, it looks like electrolysis to me. I know some of the CC do not have a common bonding system. Also I do not see a zinc on your rudder. How is the zinc on your shaft? If it was me I would replace the rudder and try to determine the cause of the erosion. Good luck, Jerry

Phosher, I am not asking about the condition of the shaft, I am asking about the condition of the zinc that is on the shaft. Do you have a sacrificial zinc on the shaft? We do on ours; the idea is that if there is any electrolysis the zinc will erode first before the shaft, prop or rudder. Jerry

got it. i'll check the pcv valve. i figured that it was the elbow piece attached via a gromet. the engine is a 351w ford commander marine.

phospher wrote: GrandSlam wrote: I am asking about the condition of the zinc that is on the shaft. Do you have a sacrificial zinc on the shaft? How would I tell if there is sacrificial zinc on the shaft? thanks!

Those are more common in salt water, and for Aluminum, not brass/nibral. If corrosion was that bad on brass/nibral everybody would have problems with their props, rudders, and fins. I still think it is mechanical damage that has been smoothed out by the abrasive qualities of water over time. Why would you have corrosion in JUST that ONE spot???

Tim