Valley gasket dry fit or jointing compound

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Allan Robinson
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Valley gasket dry fit or jointing compound

Post by Allan Robinson »

Hi guys. In the past I have always applied a jointing compound to both sides of my composite valley gasket for piece of mind safe in the knowledge that I won't get any air, coolant or oil leaks. However it is a real pain to dismantle and last time I really struggled to separate and remove the inlet manifold.

I believe I would still wish to apply sealant to the end rubbers particularly in the corners; however, other than that my question is "is it ok to fit the valley gasket dry?" after all it does have a rubbery type surface on it.

Thanks in advance
Allan



GDCobra
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Re: Valley gasket dry fit or jointing compound

Post by GDCobra »

I just took the inlet manifold off mine with composite gasket, applied with no sealant.
It took a bit of leverage to remove so well was it stuck down and the gasket had compressed quite significantly at the inlet interfaces. I can only imagine that if this would not create an effective seal you would have more serious issues and sealant would be a band-aid at best. I won't be using sealant here on reassembly.
The ends of the valley are another matter, what a poor design that is!

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ChrisJC
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Re: Valley gasket dry fit or jointing compound

Post by ChrisJC »

I always put a smudge around the water jacket connections, but don't bother with the inlet ports.

Chris.
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Re: Valley gasket dry fit or jointing compound

Post by sidecar »

I also put a thin smear on both sides of the gasket around the coolant passages. I also do the same at the front of the heads on the coolant ports that are not used because you could get a leak from that area.

Allan Robinson
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Re: Valley gasket dry fit or jointing compound

Post by Allan Robinson »

Thanks everyone and as suggested I too will restrict jointing compound to the end corners (with rubber seal) and water flanges only. This I think is a good compromise.

garrycol
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Re: Valley gasket dry fit or jointing compound

Post by garrycol »

I used to suffer a few vacuum leaks which was because with age the tin valley gasket had lost is spring and was letting air in. Since then I have always used sealant and never had the issue again.

Also I would be wary of composite gaskets as the "composite" material has been know to come away and end up in the engine - hence I only use tin gaskets and did so on my recent 4.6 Thor rebuild.

Garry

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