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View Full Version : Best lube for installing Viton o-rings



koda2
04-02-2015, 03:34 PM
I am switching from Nitrile to Viton o-rings in a hydraulic system. Tried to find out what the best lubricant is for installing these critters.

The customer service rep I talked to for Dupont would not tell me the answer till I got on the computer and filled out one of their website database forms. Then she hung up. I guess when you're Dupont you can be as **** as you want.

Does anybody know what the correct lube is? Silicone-based lube?

I found out the hard way in the past that using the wrong lubricant can markedly shorten the life of the o-ring.

Dave

chipmaker4130
04-02-2015, 03:52 PM
A typical 'best practice' is to lube with the same stuff you're trying to seal. (hydraulic oil)

Black_Moons
04-02-2015, 03:52 PM
Considered just using whatever hydraulic oil your planning on using in the system?

IMO the more important thing is to use a rubber bullet/condom/whatever floats your boat when getting the o-ring or seal over the tip of the shaft and over any circlip grooves. Once it is over that it should slide down the shaft easy with a little lube.

... And get your mind outta the gutter.

Doozer
04-02-2015, 04:42 PM
At the shock absorber factory we used to use either
Vasoline, Parker O lube, or Parker Super O lube.
We also had many many bullet tools and stretchers.

-Doozer

vpt
04-02-2015, 04:45 PM
I have had the absolute best luck using ARP's moly lube for o-rings, seals, and anything that needs lubing really.

koda2
04-02-2015, 04:51 PM
... And get your mind outta the gutter.

Not sure what you're referring to. You may have to explain it to me.

koda2
04-02-2015, 08:23 PM
Here is a new brake puck with a new o-ring installed several years ago. I think I did it but I am not sure. I (or somebody) used what was supposed to be a compatible lube. The unit was assembled but never put to use.

The interaction between the lube and the o ring produced a reaction which has begun to oxidize and corrode the slot in the puck where the o-ring sat. It is not just o-ring material on the surface of the aluminum.

http://pages.suddenlink.net/wpahpff/bad%20lube.jpg

I have seen pictures where the incompatibility causes the o-ring to disintegrate.
Thus my question about the proper lube for Viton rings.

Dave A.

boslab
04-02-2015, 08:43 PM
Watch the disintegrated viton, mainly if it's been overheated, you may find what happened to me, changing some big viton rings out of a mould cooling jacket, acid burns to both hands, I kid you not!
I didn't feel anything immediately but after about 10 mins big blisters and burning pain.
Took all my fingerprints off, handy (pun) for burglars.
We used silicone plumbers grease to lube the rings.
Mark

Willy
04-02-2015, 09:30 PM
What most folks do not realize is that there are many different formulations of the fluoroelastomer commonly referred to as Viton. There are a very large number of compounds available to suit differing applications that span a very large number of fluids, temperatures, chemicals, and they are all called Viton.

If you have selected the appropriate compound for the intended sealing application then you can do no harm using the fluid/hydraulic oil that the system will be continuously exposed to. If it's good enough to reside in the system for years on end it should suffice as an initial pre-lube as well.
Unless specifically recomended for the formulation you are using I would not be adding anything else or risk entering an unknown quantity to the cocktail party.

koda2
04-02-2015, 11:03 PM
In case you're curious I am going to use original Viton 75. It was the best compromise for higher heat although at very low temps the Viton supposedly gets too hard and will not seal. Shouldn't be a problem in west Texas.

I will be using Mobil 1 Synthetic ATF as the fluid which is mineral based so it should work. This combination has been used successfully by others for extended periods with no ill effects.

Dave A.

superUnknown
04-03-2015, 12:06 AM
Parker silicone o-ring lube. It's inert, unlike greases. And very tacky for those pesky tough-to-reach overhead spots.

macona
04-03-2015, 12:21 AM
I have some of the Parker O Lube, makes great optical matching gel...

I also use Krytox, it is a PTFE grease that is totally inert and does not have any silicones if you are trying to avoid them. I think I have 243AC. Its not cheap, but worth it.

Willy
04-03-2015, 12:38 AM
I'm sure you'll be fine irregardless of mineral based or full synthetic oil in the system.
Mobil however does make mineral based atf, synthetic blend atf and Mobil 1 full synthetic atf which is not a mineral based oil.Not that it matters as all are compatible with almost every conceivable type of seal material commonly used.
Also in the name Viton 75, the 75 refers to the durometer rating or it's hardness and conformabilty, not it's actual compound or formulation.
Like you said though many have used this same combination in a variety of applications with great success so you need not worry of it's suitability. Sometimes I too find myself over-thinking these things.LOL

koda2
04-03-2015, 11:53 PM
Willy,
You're right, I goofed. Full synthetic can not really be mineral-based. What I was trying to convey, albeit poorly, was that I was not going to use a glycol or phosphate ester based hydraulic fluid. I had the impression that Mobil 1 was still a hydrocarbon based oil even though it didn't come out of the ground.
Anyway, I finally just went with coating the o-rings with the Mobil 1. I may get some Parker O-lube or Super lube to have around for the next time.
Dave A.

CCWKen
04-04-2015, 08:27 AM
I use Nylog for automotive A/C seals. It has the consistency of honey and comes in a small squeeze bottle. I've been using it for all seal installs for years.

Mike Nash
04-04-2015, 10:01 AM
An "interesting" web page on "Full Synthetic" motor oils here http://www.synlube.com/synthetic.htm

I especially thought it was interesting that it includes

1996


SynLube introduces SynLube™ Lube−4−Life®
"The FIRST oil you do NOT change"!



then

2003


SynLube introduces SAE 0W-40 PZEV Motor Oil
SynLube™ Lube−4−Life® motor oil, specially formulated for low emission engines that are designed to use SAE 0W-20 or SAE 5W-20 motor oils.
This new formulation is suitable for 15 year or 150,000 mile service without oil changes.


I leave it to you to figure out what they are actually saying and the state of things as they are today along with whether this includes transmission fluids. I did indeed see the carrier oil disclaimer on Mobil 1 fully synthetic bottles I used to buy. I also have some old Castrol Syntec still that has separated out to some kind of sludge in the bottom. I never really expected motor oil to "expire".

JoeFin
04-04-2015, 11:45 AM
At the shock absorber factory we used to use either
Vasoline, Parker O lube, or Parker Super O lube.
We also had many many bullet tools and stretchers.

-Doozer


I'll second Parker O-ring Lube

Use it at work all the time. Has some thing in it the refreshens the O-rings. Don't ask me how - it just does. Many a time I've had leaking O-rings in pneumatic equipment - taken the O-ring out and cleaned it up with Parker O-ring Lube and reinstalled it

Black_Moons
04-04-2015, 03:27 PM
I'll second Parker O-ring Lube

Use it at work all the time. Has some thing in it the refreshens the O-rings. Don't ask me how - it just does. Many a time I've had leaking O-rings in pneumatic equipment - taken the O-ring out and cleaned it up with Parker O-ring Lube and reinstalled it

Many times seals are not bad, just have something in the way of them sealing.

Fork seals on dirtbikes are a great example of this. They invented a tool called a 'sealmate' that is basically just a little hooked shape peice of plastic you can side between the fork tube and seal to pull out dirt. Apparently most of the time they leak its just dirt that has worked its way under the seal and not the seal actually being damaged.

That said, if you are doing a considerable disassemble of anything to get at the seal, usually the cost of the $1 to $20 seal is hardly worth the chance that it is bad and you just replace it. Its only really worth trying to clean a seal if the labor to get at it is very simple, or it can be cleaned in place like fork seals.