Silicon or Viton for Fuel Cooler

[Jason789]

Hello,

I have a question and need an answer rather than an opinion.

I went to my local seal specialist and asked for some Viton O-rings to repair the fuel cooler on my D2.
The seal specialist says to me that silicon o-ring would be a better choice as they have the same heat resistance(up to 200 c) as Viton o-ring yet have a much better resistance to water.
As far as I know, the o-rings will never have to deal with any diesel fuel, only radiator fluid.
So why is it that Viton is specified as replacement for the o-rings on a fuel cooler rather than silicon o-rings, which seem to be a much better choice when dealing with water/water based products.

Cheers,

Jason

[Graeme]

I wonder if silicone's poor tensile strength and wear and abrasion resistance might be an issue, considering where the cooler is mounted.

[Jason789]

Hello Graeme,

I don't understand what abrasion and wear resistance have to do with something that is fixed in place and has no movement.

It still doesn't answer why Viton has been specified.

Viton can be made to different formulas to suit different conditions. So why is not a specific type of Viton nominated to replace the fuel cooler O-rings??

Silicon O-rings appear to be a more suitable material for the job so again,

Why is Viton specified when replacing the fuel cooler O-rings?

Cheers,

Jason

[rangieman]

As no one seems to know or bother answering :confused:
Why not give it a whirl and be the wood duck;)

[Busted Syncro]

Simple.!!!
The Viton was specified by a Qualified Design Engineer at LandRover.

The Silicon was specified by a Salesperson in a Seal shop.

You choose who you follow!!!

Chris

[Jason789]

Thanks for all the feedback,

I'm gonna go with silicon and see how it goes. Renseal in Dandenong have a good rep. So what's the worst that can happen?
Time will tell and I will give an update if it fails prematurely.

Cheers,

Jason

[rangieman]

Simple.!!!
The Viton was specified by a Qualified Design Engineer at LandRover.

The Silicon was specified by a Salesperson in a Seal shop.

You choose who you follow!!!

Chris

And for this reason we and after market company`s are improving on what these so called qualified engineers cant or did`nt do :angel:

[Graeme]

I don't understand what abrasion and wear resistance have to do with something that is fixed in place and has no movement.Whilst you might believe the cooler is securely mounted and the hose connections supported to prevent any movement, the vibrations of the TD5 engine and that the cooler is rather flimsily mounted could conceivably give rise to internal movement between the components. I don't know if this is the reason for the Viton recommendation but its a characteristic that stands-out when comparing the physical attributes of the various seal compounds.

[Jason789]

Hello again,

After some further research, my answer to the question I asked is......(it's alright, I've been wearing my foil cap :wacko::TIC:)

Viton has grade 1 degradation(which is highest/best) characteristics against fuel/oil etc but grade 2 degradation(which is lower, but not worst) characteristics against water.

Silicon has grade 1 degradation characteristics against water and grade 2 degradation characteristics against fuel/oil etc.

So, with the location of the fuel cooler and its' lack of any fuel or oil being on it for 300k km. I am definitely opting for the silicon O-rings as a replacement this time.

Cheers,

Jason