Vegetable shortening to lube o-rings?

[beviking]

I think I already know the answer to this one but thought I'd ask anyway.
I was making a crust for a sweet potatoe pie (had somone elses kids spending the weekend) and the idea hit me (*sigh* yes, others hit me too ) to ask if it could be used to lube the o-rings on a canister filter. Seems like it would be harmless to the fish but it probably breaks down rather rapidly right? If not, maybe I could mold a whale out of it and call it moby!?! And if NJ says he uses it clean his hoses...:laugh:

 

[OrionGirl]

I wouldn't use it, just because it will end up floating on the surface pretty quickly, especially in a warm tank. I think there's a silicone lubricant that doesn't break down and is non-reactive...But I'd get someone else to confirm that!

 

[beviking]

Yeah, silicone grease...it's what I use. The cost difference is huge though!

 

[JesseJ]

I've read that Vaseline works fine but I've never actually tried it.

 

[schiejr]

I used to use Vaseline until I read somewhere that petroleum based products can hasten the brittleness of rubber, although I noticed no problems during the couple of years I used it. I switched to the silicone also.

 

[BK]

on the rare occasion i need to re-lube the o rings on my canister filters i give them a quick rub down with vegetable oil on a rag, never caused any problems for me but this is on a 120 gallon so it might have some negative effects on a smaller tank.

 

[JSchmidt]

It used to be that oil (vegetable or petroleum) on O-rings was a no-no, because they would cause the rubber to break down. I don't know what they use for O-rings now, but silicone grease is certainly less likely to cause probs than some type of oil.

Jim

 

[daveedka]

Hey here's one I actually know a lot about. I have been involved in heavy mobile eqipment mechanics for most of my life. The days of real rubber being used in o-rings is pretty much gone, and modern o-rings unless they specify otherwise are designed specifically to work with modern petrolium lubricants, in the old days Gaskets were used because many oils broke down rubber o-rings. modern Durom o-rings will not react to anything but the harshest of solvents. As I don't know for sure what o-rings are being used, I wouldn't garantee that you will have no problem, but it would be very difficult to actually find and purchase an o-ring these days that petrolium product would hurt. IMO food grade oil would make more sense in the aquarium, remember that once the o-ring is in place the need for lubricant no longer exists. O-rings tend to grab by nature, so the lube is needed to assure assembly without damage, so the worry about veggy oil or shortening not staying there is not that big. If I were to use a petrolium product I would use vaseline. In my industry, vaseline is known as the fail safe assembly lube, nothing reacts to it, it doesn't plug anything up, and there are no cemical additives that will break down and change the make-up of it. it is the only commonly used lubricant that will pass through a 1 micron filter without impeding flow. Most mechanics that I know carry vaseline in their trucks for critical or specialty assemblies.

 

[JSchmidt]

That's good information, daveedka. I figured they must have come up with better materials by now. One concern I'd have about using a vegetable oil is the varnish that is left behind when it dries. If you have ever picked up a bottle fo veg. oil that had some oil left on the outside of the bottle, it doesn't take long for that oil to dry and become gummy & sticky. I don't think I'd want that on my filter... I'm pretty sure silicone grease won't do that, and I suspect petroleum jelly (vaseline) wouldn't, either.

Just a concern...

Jim

 

[anonapersona]

Eheim says...

The tech I reached by phone at Eheim says to lube all rubber parts with Vaseline every time you open the unit. Including taking off the o-ring and wiping it down completely. The filters arrive with a tiny tube of Eheim Vaseline to be used.

Apparently, regular lubrication of these parts is part of the secret to the long life that Eheim owners report.

I had a leak from a used filter I bought and was told that in as little as 18 months without regular lubrication, the Pro2 gasket might begin to leak when the unit is off. (I have a $20 gasket bought and ready for backup if the leak returns, it seems to have stopped for now.)