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Hi all
Finally got around to changing the inlet manifold to carby gasket. Though just a small amount of coolant weeping on outside, gasket finally died and dumped coolant into the inlet manifold.
Quite disturbing finding coolant spitting out the exhaust ala blown head gasket style.
Question is, why is the inlet manifold linked to the cooling system? Is it cooling or heating of the manifold reason?
As if it's a heating issue, say for cold climates, due to Perths lack of very cold mornings, I could bypass the inlet manifold altogether.
Any input much appreciated
thanks ahead
Mark
ps its a '85 L ea82 with a webber

The system is there to heat the intake manifold to improve cold running.

http://yarchive.net/car/heated_intake.html

To block off the coolant flow to the intake manifold, you would have to modify the manifold to head gaskets, as coolant flows between the head and the manifold:



I wouldn't mess with it.

The reason for heating the carburettor is for leaner mixtures not just cold running. Hot fuel vapourises much faster than cold fuel and has less tendancy to stick to the walls of the runners. The hotter the air/fuel mix is to the cylinder, the leaner you can run it.

the position of this passage may also assist in eliminating air pockets, blocking it off may cause problems

Thanks for the replies
Yes looking at it again, it does look more trouble than what's worth to bypass.
The replacement subaru gasket is lot thicker & better quality than the dead one, which appears to be card type gasket and quite thin.
mark