Anyone know the specs for the grease fitting the screws into the top of the rudder tube?
I hope you get a good answer from someone, but as a fallback suggestion it might be worthwhile to get a “nut and bolt thread size checker.” and verify for yourself. There’s a whole bunch on the market for prices ranging from $18 to $100.
Mine is on Amazon at https://smile.amazon.com/gp/product/B003FJW0GK/ref=ppx_yo_dt_b_asin_title_o09_s01?ie=UTF8&psc=1
I’ll look at my boat on Monday, and let you know what I come up with, but I don’t recall seeing a fitting like that on mine, so I’m not sure it’s a standard thing across boats.
– Bob
Solar Wind
Nonsuch 26C #143
I don’t remember the thread size but do recommend extending via an armored flex line to a Zerk fitting accessible in the port lazarette.
Dick Lane
NS26c #35 Swoose
Port Townsend
I could be wrong, but I believe that’s where a set screw goes to prevent that cap nut from turning.
Joe Valinoti
NS30 iL Gatto
Oriental, NC.
I think you’re right Joe, the grease cup is lower and in the f’glass tube.
Dick
I agree with Joe and in my experience, there are two set screws in each threaded hole, the second to prevent the first from backing out.
I had the rudder nut off this spring. I was re-sealing the bottom of the fibreglass rudder tube and lowered the rudder about 6 inches. The nut has two threaded holes which have set screws in them to lock the nut to the shaft. They are straight threads so were not designed to accept a pipe thread Zerk grease fitting,
The nut rests on a low friction Delrin plastic washer which doesn’t need lubrication. After 32 years the washer on Nature was in good condition. I did replace it but only because I had things apart and hoped the rudder wouldn’t be lowered again for many more years,.
The nut is locked to the shaft by the set screws in the two holes. I modified this arrangement by inserting a piece of brass dowel about 1/4" long in the threaded hole before inserting the set screw. This was done because If you tighten up the hard steel setscrew against the softer stainless steel shaft you run the risk of damaging the thread on the shaft. If the thread on the shaft is distorted, it will be really, really hard to remove the nut the next time. This use of an intermediate brass dowel is quite common in industry.
I also added an extra grease fitting to the fibreglass rudder tube about 5 inches below the original one. The steering was becoming stiff under sail but was fine when the boat was out of the water and no load was on the rudder.. I found when I pumped in grease it came out the top of the tube-on its OUTSIDE. It appeared the grease was just traveling up the outside of the tube, not going into inside where it was supposed to be. ( I suspect this occurred after 30 years, because I replaced the grease cup with a high pressure Zerk fitting. This would apply much more pressure to rudder greasing system)
So I carefully drilled a new hole further down and epoxied in a brass tube threaded for a grease fitting. As well I cleaned out the top grease hole and coated the inside walls of the hole with epoxy. Now the rudder is much easier to turn and grease doesn’t come out of the outside at the top anymore.
I also got the type of grease gun connector that works like pair of Vise grips. You just slip the connector over the grease fitting, close the lever, and very gently add grease. The connector comes off the same way so there are no more fights to undo it from the fitting.
John Barbour
Nature 26U toronto
Although the consensus is that the threaded holes are for set screws, rather than grease fittings, I did promise to check the thread size on mine.
FWIW, it appears to be an M7 metric thread, at least on my boat.
I can’t quite tell, but it sorta does look like there’s a set screw in there, again at least on my boat.
– Bob
Solar Wind
Nonsuch 26C #143
I am paying a lot of attention to my rudder. There is what looks like a set screw in the rudder bushing which I assume is where the grease cap is supposed to be.
Does anyone know what the thread is?
Bob’s is 7mm.
I have decided to go with the grease cap for reasons stated elsewhere, also because it is low pressure. The higher pressure applied by a grease gun will move the grease around better but it may also damage the fibreglass.
Mike Jennings.
NS005 Salt Coats.
Port Moody. BC.
My rudder Zerk fitting is 1/4 NPT
I discovered the the pull off grease gun coupler was very difficult to remove from the fitting, especially with the limited access.. Then I found this lever operated coupler on Amazon: Lumax LX-1403 silver quick release grease coupler. It has made greasing the rudder almost a pleasant experience.
John Barbour
NS 26U “Nature”
Toronto