Sealed crankcase breather system

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simonlea
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Sealed crankcase breather system

Postby simonlea » Thu Nov 25, 2021 4:40 pm

I’ve just acquired a 1962 convertible that has been re-engined with a 1098 engine. I’m told it is a fairly late model engine and probably from a van as it has a recirculating crank breather (sealed ?) system on it. I checked the engine number on the web and it suggested also, that it was from a van.
I would appreciate any info regarding cleaning/servicing the system. How does it work and what does the diaphragm unit do ?
I can’t find any info about the system on YouTube or in any manual.
Thank.....Simon

pgp001
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Re: Sealed crankcase breather system

Postby pgp001 » Thu Nov 25, 2021 6:41 pm

Hi Simon

You might find this post interesting regarding servicing the oil trap canister.

Phil P

pgp001
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Re: Sealed crankcase breather system

Postby pgp001 » Thu Nov 25, 2021 6:41 pm

pgp001 wrote:
Thu Nov 25, 2021 6:41 pm
Hi Simon

You might find this post interesting regarding servicing the oil trap canister.
viewtopic.php?f=4&t=72247

Phil P

simonlea
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Re: Sealed crankcase breather system

Postby simonlea » Fri Nov 26, 2021 11:19 am

Thank you Phil. I’m new to this, it’s my first post. I’ve obviously read your response, but I don’t know how to open the bit that shows me how to service the canister. Please explain, I feel a bit of a dunce !

pgp001
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Re: Sealed crankcase breather system

Postby pgp001 » Fri Nov 26, 2021 10:19 pm

Hi Simon

That is the point.
There is no way to service the canister as it was originally manufactured, that is why I have devised my modification to allow it to be serviced in future.

If that is something you would be interested in, send me a private message. I have already done quite few for members on the forum.

Phil P

simonlea
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Re: Sealed crankcase breather system

Postby simonlea » Sat Nov 27, 2021 12:57 pm

Are yes.....just had a lightbulb moment and figured out how to view the details of your mod to the canister. Very interesting, well done.
So that leaves me one last question regarding this system.
The diagram type thing attached to the inlet manifold...........what does that do and what maintenance does it need ?
Many thanks Phil.

philthehill
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Re: Sealed crankcase breather system

Postby philthehill » Sat Nov 27, 2021 1:21 pm

The diaphragm thing is the pollution control valve (PCV).
It allows crankcase fumes to enter the manifold on overrun.
Inside the PCV is a diaphragm with either a attached valve pin (early type) or detached valve pin (later type) that when there is depression (i.e. on acceleration) in the manifold the diaphragm pushes the valve pin onto its seat and stops engine fumes entering the manifold and upsetting the fuel/air ratio.
On overrun (no depression in the inlet manifold) the diaphragm allows the valve pin to lift of its seat (assisted by the spring) so allowing engine fumes to enter the manifold for consumption in the cylinder.
As regards servicing all you can do is make sure that the diaphragm is not punctured and the pin is able to rise and fall. The spring does suffer from corrosion and can fail.
If you have the early type of diaphragm the diaphragm is no longer available. Unfortunately the later type of diaphragm will not fit the early PCV and the whole valve has to be replaced with the later type.


philthehill
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Re: Sealed crankcase breather system

Postby philthehill » Sat Nov 27, 2021 1:27 pm

Just click on the link below & have a read of this about the PCV.

viewtopic.php?f=4&t=69311&p=630677&hili ... ve#p630677


simonlea
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Re: Sealed crankcase breather system

Postby simonlea » Sun Nov 28, 2021 6:13 pm

Many thanks for your help. All just the info I needed.


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