Will spary on silicone prolong the life of seals?

On wetted seals (like the camshaft seals and shift shaft seals), you'd lubricate with the fluid (lubricant) being retained so nothing significant to be gained by substituting something else IMO (but no experience even trying something like that for me).

On some unwetted driveshaft debris flexible seals on my Honda, I've used a silicone spray to eliminate some annoying squealing that developed later in life, but just as a lazy easy fix

 

While I am no expert in the area, but it is my understanding that silicone will deteriorate rubber products, not help it.

 

I am given to understand that silicone attacks rubber as well.

BMW sells a rubber dressing called "Gummiflage" - someone did an analysis and found it to be straight glycerine with a little blue dye in it.

I've been using it to dress the rubber door seals, etc on all my cars for years - it seems to work. Get it at your local drugstore.

 

Silicon spray & grease is the ONLY lubricant/preservative used on rubber products for scuba...petrol based products deterriorate rubber & are toxic under pressure..

 

I think you can also get some confusing/conflicting reports about "compatibilty" because of the different propellants/carriers used in spray products and "rubber" isn't always really rubber.

 

Just my 2 cents:

In a class on seals the first thing the instructor said was: "ALL seals leak." This was in the context of safety-critical seals in a refinery, but the principle is valid. The (miniscule) leakage is what lubricates the seal, but it only happens when it is running.

Best way to keep seals good is to use the machine regularly. Worst thing for seals is to sit for long periods. No special treatment is going to overcome not actually running the engine, and seals last for many years on engnes that run often and for extended periods.

Fit new seals and let it sit, they will dry out and crack, regardless. Drive the thing regularly, seals will be the last thing to go bad.

 

Silicone is a good sealer/protectant, although it will be washed off by detergents so periodic re-application may be required. Silicone is not harmful to rubbers in itself, but you should check the contents of the can you buy. Buy only 100% silicone, sometimes referred to as "electronics grade". Many of the others contain petroleum distillates that will attack many natural and synthetic compounds, causing pre-mature degradation of the rubber or plastic. It is also probably best used on parts that are not exposed to oil or fuel, such as door, trunk, hood seals, etc.

Regards,
Bill

 

I use Dow Corning 111 Silicone paste for installing "all" new o-rings and radial seals. Discovered it years ago and use it building all engines and trans and now every seal on the car i.e front and rear main seals, cam radial seals, the rubber part of seal in contact with the shaft in water pumps upon rebuilding, even the o-rings for cam bolts,

I've never put stuff on after the fact to make them last longer other than changing the oil regularly then as that's now your lubricant.