I pulled the leaky rudder shaft to perform a proper repair on my 28' express. Now I just need to learn what a proper repair is. It appears the steel shaft simply pivots in the steel of the hull? Am I missing something? Wouldn't steel-against-steel promote wear and corrosion? Is there a better way to put this back together? I'm thinking of honing out the hull, pressing in a bronze bushing, and maybe getting stainless rudders fabricated? I searched old posts. If I missed some info on the best way to fix these, I'd appreciate any references. The hull is in need of stripping down to steel and a complete recoat after the rudder and shaft seals are addressed.
Hi, I seriously doubt if your rudder post was designed to run in a steel to steel contact arrgt. There would normally be at least one bearing in the lower section that gives some length for shaft stability and the sealing setup at the top with some means of stopping the whole lot falling out the bottom of your boat. I am sure that one of the CC Gurus will give you the drum when they see this, I know that at least one poster here has had major rudder battles that he posted pictures of.
Check the Roamer threads. I seem to recall reading about this very situation with one of the rebuilds, and a rudder was rusted solid. If I remember correctly there was a vivid description and pics.
NYCAP- Where you thinking of this one? I have inserted a link for post 64 which is where the rudder stuff starts. http://www.yachtforums.com/forums/72761-post64.html This is the original thread it came out of. http://www.yachtforums.com/forums/chris-craft-roamer-discussion/8178-found-roamer-46-a.html
So, the "log" is the tube that is welded into the hull? I see that aluminum Roamer has a grease fitting on the log. That looks like a good idea. I don't think mine has grease fittings and no trace of a bearing surface inside the log. Hard to believe that's the way it was engineered?
Will I be in danger of setting up a bi-metal, corrosive reaction if I put a bronze bushing in the steel hull? They used HDPE on that aluminum Roamer. I can get a pair of stainless rudders built locally for $650. I intend to make the rudder shaft diamer slightly smaller to give me room to put a bushing in the hull. I'll ream the logs just enough to remove pitting and press the bushing in from the bottom. I would like to find a way to keep the steel from rusting behind the bushing. At least I won't have rust building up on the surfaces that move against each other.
Hi, One way to make sure there is no water in between the bronze bushing and the steel tube would be to make sure the inner bore of the tube is spotless and de greased apply a good smear of bedding compound and then push the bushing in. This should allow the bush to remove the compound from the high spots and leave it in the hollows and low spots. It would also make some sense to have a mechanical securing of the bush to avoid it moving in service amd cauing problems later, this can be as simple as a grub screw through the tube from the outside in a couple of spots. There should not be any bi metallic action problems with bronze and steel in close contact. Another good feature is to get a couple of grooves machined on the inner bore of the bush and drill for greasing, fit a grease nipple and use it regularly, this should give a long trouble free life to your new rudders.
rudder bearing Just a few thoughts, 1. According to the people responding to either rudder thread, no one has found their original CC lower bearing. I think it's because there was never a lower bearing. And 51 years of service on biodon's boat should indicate the original engineering was adaquate. 2. The grease zerk on the AL roamers probably (my observation) served two purposes - a. to lube the rudder shaft/log contact (steel shaft against alum log will wear the alum) and b. to offer some barrier between sea water and the al/bronze bi-metal coupling above. On my 58, that grease zerk was never 'greased' and the bronze packing gland ate the alum log at the threads. It was only 32 years old. I personally think that 32 years is a satisfactory life expectancy with no proper maintenance. 3. Si if you re- design this basically simple mechanism, do the math before you reduce the diameter of the rudder shaft, they were disigned for the torques applied. A very small reduction is diameter can be a big reduction in strength. (a sidebar for those increasing HP - more speed means more torque on the rudder). So - why wouldn't a person re-pair the system to it's original design and service it again in another 51 years? Just my thoughts
Because by that time if still alive they would be living in a rest home and not remember of they had ever owned a boat or had breakfast 10 mins previously!! That was a very good point you put in about the reducing of the rudder stock diameter. I was thinking abut that whilst typing but somehow the thought got misplaced between my brain and my fingers by incessant nagging about sitting in front of TV watching the Le Mans 24 hr and surfing the net.
The original rudder shaft is slightly larger in diameter where it goes through the hull than the upper part of the shaft. It will be easier to manufacture the new rudders with a single, rather than stepped diameters. I save a little machine work, gain space for a bushing, and the effective diameter is no smaller than the original upper part of the shaft. Could it be that this stepped diameter design was to provide a wear surface that could later be machined and replaced with a bushing? I hear what you say about having faith in the original engineers. It just bothers me to have steel rubbing against steel below the water line. It seems like a little rust bubble would grow every week, just to get knocked off each time the boat is used. It may have lasted 50 years, but it started rusting from day 1. I like the grease zerk idea. Seems like grease under the packing gland would make that seal more effective as well. The risk I see is that the zerk itself would have to be watertight. Maybe this is getting too far from the original design?
Hi, Here is a selection of fittings, all have springs and balls in them so they are effectively one way flow devices, water will not push out the grease and leak into the boat. http://www.rwsupply.net/index.php?main_page=index&cPath=23
I wish someone could explain to me the wisodm of the Cris Craft engineers. Then I would be happy to put it back just the way it was. What is to keep the rust from inside the rudder log from propagating out along the surface of the hull? I am backing off my bronze bushing idea. I can concieve that rust between the steel log and the bushing could eventually swell, squeeze the bushing, and cause the rudder to seize. At least the rudder shaft turnging agaisnt the steel would have the opportunity to wear away the rust bubbles. I still see nothing wrong with new rudders of stainless steel. I was thinking that I could do away with the zinc anodes on the rudders if the rudder were stainless, but I suppose that anode still protects the hull, doesn't it? Where is a good place to get anodes? I heard they have special makeup for certain bodies of water.
Hi. I'm the guy with the 46 Roamer with the aluminum rudder logs/plain steel shafts/bronze glands that turned to unimetal. A commenter or two without actual experience with these boats have insisted that there are bushings or bearings on these things, but I assure you there are not. I, too, initially could not fathom why CC engineers would do such a thing. But Artwork makes several good points, as usual ;-). One observation I would add to what Art mentioned about yours lasting 51 years is that my boat did not move for 25 years and that zirk fitting was probably never greased after the first time at the factory. It should not be seen as a design flaw if your rudders were a bit rusty after that much time or mine were frozen solid because of lack of use AND no maintenance over time. If you pretty up the original arrangement, install a zirk, and simply use the thing, rust will have a hard time building up on the shaft or log. The rotation of the rudder should turn any such rust to powder, which will likely wash out of the space between the log and the shaft. One other thing I might recommend if you go with a zirk fitting is to make it easy to access. You might even consider using 1/4" tubing and fittings so you can have a remotely mounted zirk that you can access without dismantling anything.
I decided to put it back as it was, with the exception of new stainless rudders. The old shafts had rusted to where they rocked back in forth in the logs, that made the seals pretty short-lived. I'm concerend about the logs rusting. I'm not worried they will sieze. I just don't want to loose any steel, and I don't want my new bottom paint to be compromised.
Gotcha. I see from your original post that you're stripping it down to steel, so presumably you'll be applying an epoxy barrier coat once that's done. If you're really concerned about losing log material, that would be the time to cut out the old log and have a new one fabricated that can accommodate a bushing. Intuitively (to me, anyway), a bolt-on bushing would be preferable to pressed in one. Is the original log in bad shape?
There is some pitting around the lower part of the log (on the water side), but I consider them to be solid. I've cleaned them up inside and out. I'm going to coat the inside of the tube with POR 15. I expect it to wear off of the high spots. Hopefully, it will stick to the low spots and retard any corrosion. I decided to leave all the original metal in place rather than remove any material to insert bushings. I like your complete rebuild idea. I'm not sure that investment is warranted right now. I will have some time to think about it as I've decided to go ahead with the complete hull paint job-inside and out before it goes in the water. I was tyring to get it in the water at least briefly this season before stripping it down. I changed my mind when I exposed a pea-sized rust hole through the hull. It is a discrete hole in the middle of an area with no pitting. It will be very easy to weld shut. It is not what I would consider cancerous, but decided the entire hull needs cleaning and thoroughly inspected to make sure there are no similar spots lurking. I intend to strip and sandblast the outside of the hull-at least for the water line and below. I haven't decided whether it is prudent to take the upper hull down to bare metal. Was the steel originally smoothed to a paintable finish, or are there factory-applied fillers to make a smooth visible surface above the water line? I have yet to begin my education on new coatings. I trust I will find info in the archived posts. For the inside of the hull, I intend to wire brush and scrape everything below the water line and coat with POR 15 or appropriate coating. I expect to pull enough flooring to get to every rib joint.
