Epdm Rudder Bearing Rings / REFER TO RUDDER BEARING THREAD
Awhile back I yacked about the rudder bearings rings Bill and Gene have for the bearing sleeve. When you get a new bearing, you get O-rings with it. The O-rings are serviceable neoprene.
However EPDM in
weathering/ozone,
wear/abrasion,
sunlight resistance, and
compression set...
is far superior.
I promised I would get the new rings to Gene and never did, mainly because I wanted to put them up in nice little plastic baggies.
Got all the pieces together but never put the rings in the baggies.
If anybody specifically wants a set of EPDM rudder bearing O-rings let me know and I will mail them to you. No Problema! This until I get them over to Gene as I promised.
I believe that A/C rudder bearing rings need replacement much like you get worn brakes on your wheels replaced.
They do wear out. The smaller inside one, about 100 times faster than the one against the tube.
They are fairly easy to replace as a maintenance item.
PM is good for a mailing address.
Need a complete name though!
EPDM (Ethylene, Propylene, non-conjugated Diene, and Methylene) is presently THE outdoor rubber of all synthetic outdoor rubbers.
It's used for weather stripping - seals - gaskets.
Tubes and hoses / hydraulic brake systems - tires.
Washing machines, dishwashers,
pond liners, membranes, roofing and coatings.
All the exposed rubber on vehicles is likely EPDM.
Due to its completely saturated hydrocarbon main chain (thought you'd like that!), it is highly resistant to weathering, UV, and ozone. It's highly resistant to aging by oxygen, heat and oxidation.
Is highly resistant to animal (ie lanolin) and vegetable oils, steam, and oxygenated solvents like acetone and ketone (MEK).
It's NOT good with petroleum based products.*
It is not the most resilient of rubbers, but its good points far outweigh its mediocre - including its relative low cost.
Neoprene, when not a foam, is associated with oil and gas, used 'under the hood'.
EPDM IS SUPERIOR IN SALT WATER ENVIRONMENT TO NEOPRENE.
How many times have you seen sun and saltwater compromised wet-suits??
O-rings are sized by number and come in maybe 20 different plastic-rubbers and qualities by who knows how many manufacturers. McMasterCarr is this source and I'm assuming their O-rings are good quality. Suppliers usually have fluid compatibility charts and material application rating guides. So you can check it out too!
The standardized DASH number size for our very common sized rings is -214 and -218, at least in the States. There is no information in the code number as to what material it is.
Talking about the material: No O'ring has a better WEAR/ABRASION rating compared with EPDM except urethane which is superior. But its compression rating is poor along with neoprene. EPDM has the best score, imco, in the four O-ring points mentioned above.
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*Pandora's Petro Box includes: petrolatum jelly (vasoline), paints, varnishes, lube oil (3-in-1 oil, WD-40, Tri-flow with teflon, etc.) , grease, paraffin wax, kerosene, gasoline, diesel, naptha, propane, butane, toluene, xylene. The building blocks of EPDM are ethylene, propylene, methylene,,, all petrochems. Like dissolves like, eh?
SO, if you feel the need to lube your EPDM O-ringed rudder head, DON"T with any of these or their 10,000 derivatives. A good alternative might be anhydrous lanolin, Lanocote. The inner O-ring is constantly moving and in need of protective lubrication, imco. Nothing silicone based - EVER.
I have said rudder tube fitting here in my hot little hand. If this is in fact the correct rudder post fitting then yes please new rings would be fantabulous. If not then I guess I'll be ordering a new one from Gene. I did notice lots of play in the rudder before haul-out. Wonder if it was the crappy fitting or the loose boards on the rudder itself?
Andrew,
THAT is indeed the bespoke fitting. The outside O-ring is flatter than a pancake. The inside O-ring is even flatter. Just a guess.
Has to be your call on the sleeve bearing. Somebody here knows what it's made out of...? canvas/phenolic? It has aged, but is it still unchipped, uncracked etc? 338's was broken. Maybe that one there is a little out of round...h m m m m m?
IF the rudder shaft has been slopping around unprotected by the O-rings in the sleeve bearing, we'd have to assume that in 20 or 40 years some wear or distortion has happened. Check it out with a micrometer and the stats in the Manual. Imco
If you get a new beautifully machined black delrin* one from Gene, it will come with the neoprene O-rings.
The new sleeve and rings is an exact replacement in specifications for the one in your hand. The materials are modern. Yet Neoprene is often said to be the first synthetic rubber invented (Dupont 1930 - same year as nylon - epdm seems to have sponteanously hatched unremembered) - maybe the first Pearson/Ariel O-rings were neoprene? Being first doesn't make it better!
The rings in that bearing have an antique look to them.
Has to be your call whether new rings in the old bearing will work well. Why not? One replaces seals when the old ones wear out allatime!
Yeah, right! BUT will you remember? ....When your rudder gets sloppy again.
For anybody else here, you'll want a set of dental probes to get the inner seal out. Hopefully it won't be difficult. Keep the O-ring ways as pristine and ungouged as possible. One of those probes (the right angle one with the little extra hook in the tip...) was made just to lift the old ring out. They are hardware items (General?) sold in sets of three or four.
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*Delrin, Dupont acetal homopolymer, is a very hard plastic - whose primary use seems to be as a bearing material - that has very low water absorption, high resistance to fuels and solvents - but is not inherently UV stable. Carbon is added to black Delrin, which officially increases its life expectancy to 20 Dupont years. Our ap has it covered and not in direct sunlight.
So you think this was the original bearing? Wow! It is in remarkable shape considering. The rings are not really rings anymore more like pathetic pieces of rubber pretending to do a job.
I will order up a new one. If you could send upgraded rings that would be perfect! I can save the neo ones as back-up!
Epdm Rudder Bearing Rings / REFER TO RUDDER BEARING THREAD
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