Frank Auto-Rx Seal Question?

[JohnBrowning]

Frank I am woundering about seal integreity and synthetic esters? You have stated a couple of times that you think that the synthetic esters are damageing seals? I would like to understand more about this because. Are we talking about viton seals, nitril, silicone, ruber.......?

I ask because most if not all of the seals on my New car are made out of some really high grade viton materials.

Oh I also wanted to ask you about Polymer Amines in oil. I was reading some Dupont papers on Viton the other day and it stated that amines were very hard on Viton. Could high amounts of amines be what is attacking some seals?

Thanks for your time Frank I look forward to learning more about this!! I thought they solved this years ago? Always learning!

P.S. Happy New Year and God Bless every one!!!

[ January 01, 2004, 12:47 AM: Message edited by: JohnBrowning ]

 

[Rick20]

John,

I had thought that most rotational seals in motors were of nitile rubber. Of coarse there are probably thousands of formulations of nitile rubber depending on application. It is interesting that as you state a new car of yours uses a flourocarbon rubber formulation. Very expensive seal material.It has much better properties as far as operating temperatures. The material is typically good from minus 30 C. to 220 C. Far better on the heat side. Its use in crank seals would typically be high temp. high rpms. Howver, a noted weakness of flourocarbon rubbers are high concentrations of esters, amines, ethers, and ketones. Sounds like synthetic oils, high in ester content my be an issue. I would doubt that a motor oil would carry a large does of amines in it formulation. However definitly a small amount to bond with metal and protect from reactive components looming around the crankcase.

But seals are a funny topic. Whenever some great scientist invents a new polymer or rubber formulation. For its newly found great qualities, there is always a weakness. Its too bad the best resistance qualities of all the seal materials out there could be captured in one material.

 

[Rick20]

I am sure that this new high tech viton material is fully compatable with any motor oil. I am sure that the incompatability issue is aimed at esters of an industrial solvent nature.

On another note, seal failures, are a great topic.
Its interesting that dino oils get the rap that they shrink seals, oxidize, and a major cause of oil leaks, if you listen to the synthetic oil users. Conversely, PAO oils are outfitted with additive that actually swell seals, to counteract the shrinkage from the PAO.

But at the end of the day, keeping a clean crankcase and never overheating your motor is about the only defense in preserving seals.
Heat and contamination are probably the biggest two enemies. The addition of incompatible additives and solvents, is also a big contributor.
Both from a directly incompatible nature, as well as knocking the host oil balance off to the point whereby the adds fall out of suspension.

 

[Robbie Alexander]

quote:

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Originally posted by Rick20:
John,

I had thought that most rotational seals in motors were of nitile rubber. Of coarse there are probably thousands of formulations of nitile rubber depending on application. It is interesting that as you state a new car of yours uses a flourocarbon rubber formulation. -*-*

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Sounds like you know something about seals.
Would you now how I could get the BEST aftermarket seal material for Toyota?

Theres seems to only last about 100-150K without leaking... I would like one to last at least 250-300K because that is the time I do my clutch.

What would you think on this type of Amine on a TOYOTA seal material either front or rear (I assume both are same)?

Would it be better If I treated the oil or did a maintenance additive in the oil to condition the seals. I want to go 250-300K with no leaks... I have done it on other cars, but not this one.

 

[JohnBrowning]

Rick 20 I am assumeing this. I say this because in the past the rear main seals on the 22RE I had to replace said VITON right on them followed by that little trademark "R"! These were not OEM though. I should have better qualified my statement as an assumption on my part based on past replacement parts.

I thought that chlorinated florocarbons and PRF enhanced florocarbons were fine for use on internal combustion engines?

See if NOK makes some for it. NOK CNC machines their seals from a solid piece of whatever material they choose to use. Next inline would be to contact Felpro and see what material they are useing. I wish I remembered the company I got the old rear main seals from. I was working for a high end import garage at the time and just used our normal supplier.

[ January 02, 2004, 11:50 PM: Message edited by: JohnBrowning ]

 

[JohnBrowning]

Could they use a lament of seal materials. I know in Aviation we have several different types of wire insulation to choose from. SOme have multiple layers of different florcarbons layered like a sandwich!

I am actualy just learning about florocarbons right know!

 

[MolaKule]

I have tested various elastomer seals in pure polyol esters of ISO 68 and 100 viscosities and have never seen any seal damage or material changes.

Elastomer seal materials are used in modern refrigeration compressors and must remain intact for at least 100,000 miles. The lubricating fluid is either a polyol ester or an ester of PEG. In my view, modern esters for PCMO formulations do not cause seal degradation.

Some early diesters had an affinity for elastomers and did excessively swell seals, which caused subsequent leaks. Those esters have not been used for over 30 years.

As I have stated elsewhere, the destructive polymers in sludge are the primary cause of seal degradation. Prevent sludge buildup with ARX or LC, and the seals should not degrade.

[ January 03, 2004, 02:32 AM: Message edited by: MolaKule ]

 

[nick778]

...or use a high quality PAO/Ester synthetic changed at prudent intervals which is less prone to sludging in the first place?

 

[JohnBrowning]

I know I am considering useing LC to keep sludge polymers at bay! I have also considered useing Auto-RX every 50,000 miles as a preventive maintence item! I can not imageing that useing synthetic oil and Auto-Rxing it ever 50,000 would not keep it clean.

I have never had a sludge issue on any of my cars or trucks before. Even when I used to use Castrol GTX 10W30 and 20W50 I never had a sludge issue. So this would be just to keep everything in tip top shape!