[Healeys] BN1 PCV system

[Bob Spidell]

The best place for a fresh air source would be a small filter on the oil 
filter cap. Obviously, not an easy thing to rig up. Or, you could put a 
tube on the backside of one of the carbs, but you'd want a better filter 
than the stock grasshopper-stoppers.

On 1/30/2021 3:48 PM, Harold Manifold wrote:
> I am also looking into a PCV system for my BT7 as well. Most of the PCV
> systems I have seen on Healey's don't have a filtered fresh air intake and
> don't have much ability to replace the blow by and other nasty's that will
> accumulate in the bottom of the block. To have air changes in the bottom of
> the block a filtered fresh air source is needed and slight vacuum to draw
> out anything that accumulates. Ideally the fresh air would come in at one of
> the block and the bad air leave at the other end. There is a connection
> between the tappet section and the bottom of the block but this is also the
> oil return. (A BN1 engine may be different) A PCV can be used to control the
> system but if the air circulating bypasses most of the engine then the
> system is less effective. On V8 engines the clean air comes in through one
> valve cover, passes through the bottom of the block and then exists via the
> other valve cover drawn by vacuum from the intake.
>
> Any good ideas where to locate a filter fresh air source?
>
> This website has excellent information on PCV valves and is where I found
> the attached article by Tony Ball.
>
> http://mewagner.com/
>
> Harold
>
>
>
> -----Original Message-----
> From: Healeys [mailto:healeys-bounces at autox.team.net] On Behalf Of Bob
> Spidell
> Sent: Saturday, January 30, 2021 2:41 PM
> To: healeys at autox.team.net
> Subject: Re: [Healeys] BN1 PCV system
>
> Looks clean, Michael. I am considering similar for my BN2 (but I plan to fab
> a plate with an elbow to replace the road draft tube). If you plug the valve
> cover vent, you'll have a 'system' similar to what I have on my BJ8, which
> is an updated version of the original Norman Nock design.
> This isn't really a PCV system, as the crankcase and valve cover will be
> under continuous vacuum. I suspect some air is drawn in from the rear
> 'seal,' which is not filtered but helps to alleviate the infamous Healey
> bellhousing drip, and likely doesn't affect mixture all that much. If you
> leave the vent open--I'd put an air filter on it--you'll have a genuine PCV
> system as air will be constantly circulated through the crankcase and top
> end. This is what I plan to do, but my 100M is vented to the CAB, for which
> I have a large K&N filter on the intake duct in front of the radiator.
>
> Which PCV valve did you select?
>
> Bob
>
>
>
> On 1/30/2021 12:20 PM, Michael Salter wrote:
>> After months of deliberation I have constructed this PCV system for my
>> BN1.
>> The original road draft tube has been plugged just below the PCV valve
>> takeoff.
>> Of importance was that the system would be almost impossible to see
>> without very close inspection.
>> I'm still trying to decide if I should plug the normal valve cover
>> vent or leave it open to serve as the PCV system intake.
>> Thoughts?
>>
>> M
>>
>