Are You a Greaser?

[rognvald]

No, not the people who grew up in Chicago during the 50's and 60's who wore black leather jackets, sharkskin pants, Italian knit sweaters and exhibited anti-social behavior but rather a lubrication specialist with specialized knowledge of greases. I am preparing to reinstall my rudder after a complete rebuild of my rudder and steering system and would like opinions on what would be the best lubricant for the shaft, rudder bearings and bearing tube: marine bearing grease or Lithium grease? All comments are appreciated.

[CSY Man]

I have always used marine wheel bearing grease for trailers, a few bucks at ACE hardware and seem to be good stuff. It came recommended from Simpson Lawrence when I re-built my 555 Sea Tiger. Have since used it on winches, steering and stuff.

[donradcliffe]

Go down and talk to to the greasers at the greaser store--there are literally hundreds of greases. My personal recommendation as a part-time greaser is:

Don't used lithium based greases, especially in salt water.

I'd go with something like DuPont Teflon Marine Waterproof Grease, 16 oz tub

[Downtime]

Don't use marine wheel bearing grease on your rudder shaft or really anywhere on your actual boat. It is sticky and your wheel/rudder won't turn as freely or be responsive.

[colemj]

What type of bearings are they? For some, like PTFE and Delrin, it is often advised against using grease with them. The bearing tube generally doesn't need any grease because there is no contact with anything except the bearings - and you want those to be stuck in it, not moving around.

Mark

[rognvald]

Originally Posted by colemj

What type of bearings are they? For some, like PTFE and Delrin, it is often advised against using grease with them. The bearing tube generally doesn't need any grease because there is no contact with anything except the bearings - and you want those to be stuck in it, not moving around.

Mark

Mark,
The bearings could be either. I haven't confirmed this at a plastics shop. There was, however, grease on the whole assembly when I pulled my rudder. I cleaned out the rudder tube,bearings and shaft with degreaser and they are free of grease. The lithium suggestion, Don, was from our local boat yard(Lake Michigan/fresh water) but we previously lived aboard for 10 years in South Florida/Islands. I need to get this right since it is expensive to drop the rudder again. As a side-note, we hope to return to salt water shortly and this is the overriding consideration. Thanks.

[donradcliffe]

Your rudder bearings are probably Delrin sleeves.

Delrin swells 1% in water, but has good compatibility with most greases.

Delrin to steel has a 0.2/0.35 static/dynamic dry coefficient of friction, which is not particularly low unless they used the fancy slippery 500CL or AF (not likely).

The rudder bearings can be pretty heavily loaded on a reach and are definitely low speed bearings, so ignore the bad advice on this forum and slather on some good, sticky waterproof grease--it will also help keep the dirt and salt crystals out.

If the rudder is out, now is the time to put in a zerc fitting in each bearing so that you can inject fresh grease with a grease gun--just drill and tap the bearing case for the fitting, then drill a small hole through the plastic.

Read Dupont's recommendations for lithium vs marine grease http://www2.dupont.com/Consumer_Lubr...ts/grease.html

[colemj]

Maybe ask the bearing manufacturer? I know our Tides Marine HMWP state not to grease them. If you do grease, and do not have a manufacturer recommendation either way, I would use a synthetic PFTE grease like SuperLube.

Mark

[Cheechako]

If you have any sort of plastic bearing don't grease it. The grease swells the plastic over time, making it worse than no grease. If you have bronze bearings I would use the thickest stuff meant for underwater use.

[colemj]

While true for some petroleum-based greases, most plastics used in these applications are compatible with the synthetic greases that are most common today.

The bearing manufacturers are usually specific about this. If one instructed not to use grease of any sort, I would not consider that bad advice.

Mark

[captain58sailin]

I generally use the red sticky stuff on everything, including my packing gland on my propeller shaft.

[rognvald]

So, the bearings are nylon . . . ergo--no grease on the shaft or inner bearings? Life would be so less complicated without marine obsessions . . .

[colemj]

Nylon is compatible with many greases. Is this reinforced nylon? Many of the reinforced nylons used specifically for bearings have solid lubricants as fillers so that they are self-lubricating.

Did you have these made out of nylon stock, or bought from a company? If from a company, did you check their recommendation? If made out of stock, do you know what kind of nylon?

Most greases won't hurt the nylon, but could trap dirt, etc in the bearing surfaces.

Mark

[rognvald]

Originally Posted by colemj

Nylon is compatible with many greases. Is this reinforced nylon? Many of the reinforced nylons used specifically for bearings have solid lubricants as fillers so that they are self-lubricating.

Did you have these made out of nylon stock, or bought from a company? If from a company, did you check their recommendation? If made out of stock, do you know what kind of nylon?

Most greases won't hurt the nylon, but could trap dirt, etc in the bearing surfaces.

Mark

Mark,
They are nylon but I don't know if they are reinforced nylon.
They are the original bearings and still serviceable. So, to grease or not to grease . . . that is the question.

[rognvald]

Originally Posted by rognvald

Mark,
They are nylon but I don't know if they are reinforced nylon.
They are the original bearings and still serviceable. So, to grease or not to grease . . . that is the question.

After taking the bearings to a plastics shop, they are confirmed to be Delrin. So much for nylon and the issue of grease. I believe I will polish the shaft and reassemble. Any comments to the contrary or is the world finally wine and roses?