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Re: Crankcase Breather Smoke
Posted: Tue Oct 06, 2026 3:20 pm
by Bill_qaz
Oliver90, We are all entitled to are opinion.
But I hardly think a heavy breathing classic car is contributing to planet decline or harming pedestrians
You can love your EV's and feel good about you contribution to the environment.
But I can think its a lot of marketing BS and refuse to ever consider an EV.
It doesn't make either of us wrong(or me a ludite) it just different opinions and beliefs.
Re: Crankcase Breather Smoke
Posted: Tue Oct 06, 2026 9:10 pm
by svenedin
Is a squabble about electric battery carriages helping the OP with his engine issues?
Stephen
Re: Crankcase Breather Smoke
Posted: Tue Oct 06, 2026 9:27 pm
by svenedin
This is the manifold 12A1097 that has a tapping for a PCV valve and is also tapped for the stud (or machine screw) to hold a Smiths PCV valve bracket. Also the oil separator "chimney" tappet chest cover. This is filled with wire wool so that the oil from the fumes is separated out (or at least most of it). The fumes are then directed via a special oil resistant pipe to the Smiths PCV valve and fed into the inlet manifold to be burnt in the engine. This would sort out the issue of the "smoke" from the engine. It is exactly the reason this closed-circuit breathing was introduced; to prevent crankcase gases being vented to atmosphere causing bad smells and atmospheric pollution. It was used on engines starting 10ME around 1968/1969 in Minors. A bit later the system was simplified by directly sending the fumes from the oil separator to a variant of the HS2 carburettor with an inlet for the breather pipe. The PCV valve does have limitations; if the blow-by is very severe it can overwhelm this breather system.
Stephen

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