? Silicone "Coating" in valve covers

[Francois25]

                                                                                                                                                                                                                                                        Has anyone else seen a thick coating of what appears to be silicone or something similar ? What do you think it's for? My guess would be noise reduction or stopleak. Also, what is the rivet for in the middle of the valve cover? Thank you for any input.                                                                                                                                                                                                                                                                                                               

[Cam3512]

Definitely a lame attempt to silence the tappets. 

That IS the Guzzi music!

[Antietam Classic Cycle]

What Cam wrote. I'd remove it as soon as possible. No idea what the rivet was all about.

[Dirk_S]

…or perhaps to hide/cover up a crack?

[chuck peterson]

On a tangent to this…

Tomb is always quite proud of a set of valve covers from a company called Blake, if I recall..

A bit taller with additional finning, the inside was indeed layered with some heat/oil resistant thick coating (rubbery)  to reduce the tappet noise..

[Chuck in Indiana]

On a tangent to this…

Tomb is always quite proud of a set of valve covers from a company called Blake, if I recall..

A bit taller with additional finning, the inside was indeed layered with some heat/oil resistant thick coating (rubbery)  to reduce the tappet noise..

Yeah, those are pretty rare these days.

[Wayne Orwig]

One issue with the Guzzi is that the valve covers stuck out there in the cold air get a lot of condensation in them.
Maybe it was an attempt to insulate the cover, and maybe reduce the condensation.
Interesting idea, but having the silicone disintegrate inside the motor would do more damage than the moisture.

No idea on the rivet in the cover.

[John A]

Maybe he used the rivet to plug a hole from a previous attempt at what he was trying to accomplish.

[Chuck in Indiana]

Maybe he used the rivet to plug a hole from a previous attempt at what he was trying to accomplish.

I would say that is as good a guess as any. I believe the "Tips" book said a feminine napkin would quiet them down. 

[Francois25]

Thanks for your replies. Should add that valve covers are off of non-running parts motor that I purchased. Motor has cast-iron liners so I know that's something to work with. Will probably never use these valve covers , but if I do I will clean them up .

[guzzisteve]

I was just going to ask if you were from IL. I used to see all kinds of stuff glued or what ever in the covers. Silicone and felt mostly. And the rivet, well, seen stuff like that before too. That was supposed to stop the ringing some would have or heard. Seen a half of stick of stick on wheel weights on top of the fins.

[Burkslaw]

That is fossilized amber. Your Guzzi was built in the Pleistocene era.

[ccoli]

Heard about folks finding indoor/outdoor carpet glued inside of valve covers in order to quiet the valve noise.
That's not noise that's music!

[lucky phil]

I would say that is as good a guess as any. I believe the "Tips" book said a feminine napkin would quiet them down. 

Didn't you have a rocker cover porosity issue at one point Chuck?

Phil

[Cam3512]

And, they make fantastic hand warmers in the cold weather!