PCV valve

[les]

I’m checking this item, there seems to be what looks like a plunger in the centre of the valve, I think it should be free to move, am I right ? I can’t find an exploded view, which would be helpful.

[firedrake1942]

This is, I think. the Smiths PCV valve like the one on my 1957 948cc Minor.

[svenedin]

Yes, part 34 in the diagram above is a plunger that is free to move against a spring. It is important to note that there is an earlier type and a later type Smiths PCV valve. The later type has a replaceable diaphragm (part 33). The earlier type has a diaphragm that is fused to the top plate and replacements are not available.

Stephen

[les]

Many than thanks to both for the diagram and info. I’ve got no movement at the check valve No 5. Will need to investigate, there looks like a type of circlip holding the centre assembly to the main body. Not sure it’s dismantleable though.

[svenedin]

Many than thanks to both for the diagram and info. I’ve got no movement at the check valve No 5. Will need to investigate, there looks like a type of circlip holding the centre assembly to the main body. Not sure it’s dismantleable though.

That check valve tends to gum up with tarry oily fluid and if your valve has not been used for a long time this is what I would suspect. Carburettor cleaner dissolves this gunk very well. If that fails try soaking in fresh petrol.

Stephen

[les]

Sounds like a plan Stephen, that’s my next move then.