WRD Sealant

[Runale]

Hi all,

I have noticed that the warm running device is sealed with some sort of silicone or rubber sealant.  Does anybody know what it is?  Its function could possibly be to avoid coolant from the upper chamber of the thermostat leaking into the fuel injector.  If this is so, can someone shed light on a proper re installation apart from what is shown in the technical manual?

Thanks

Alessandro

[Pawel66]

Yes, the sealant is there to prevent coolant from getting into the air valve that is below as it could make it stuck over time.

Any engine sealant is fine. Just apply not too much on the edge.

[Runale]

Thanks

[wwheeler]

In theory, no sealant is required. It is a machined tapered face seal that is held together in compression. When new, no sealant was used and was simply a mechanical seal. However with time and age, very small imperfections can form on the sealing faces. Just make sure the sealant is water resistant and rated for at least 300*F. And Pawel said, very little is needed. More is not better.

[Runale]

I got a high temperature engine sealant and made a very thin line. Thanks for the advice guys much appreciated.