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[dublin.jd]

Thanks chrisgixer, when I clean breathers that includes breather box, plenum and throttle body. But I don't care how methodically or regularly u do that, the gaskets will eventually leak oil. They don't need to block for long to blow the gaskets and that can happen for any reason and at any time.
Anyway was just wondering if anyone has any ideas that would compliment the original breather set up and regular cleaning of the original set up
Thanks
Ps. I already know how to clean the crankcase breather assembly and associated pipes/hoses etc  just for anyone who hasn't read previous posts.

[chrisgixer]

When I said 4 covers I meant the intake and exhaust side of each cover. Obviously 1 hole or valve on each bank would do. You knew what I meant?
And if the cam covers where under negative pressure the wouldn't blow oil everywhere. They would suck air In !

So why ARE THEY LEAKING THEN? why would the c case need to run at negative pressure? What about blow by gases from combustion. As Kev says, drill holes in the covers, or vent the c case, the breathers will suck extra air into the plenum, which will give you, of all things A FUEL TRIM ERROR!

Any light bulbs yet?

The seals don't last forever, how many miles on the 2.6. ? 80-90k on the clock and they go hard anyway.

[dublin.jd]

I'm not trying to run at negative pressure? That wouldn't make sense. It's a build up of positive pressure that makes them fail. Vaccuum is created at inlet and not the cam covers. Drilling a hole in c cover shouldn't affect vacuum. But drilling holes regardless of size wouldn't be good, I just said that to get the jist across. Pressure relief valves was more what I meant. As they only let pressure escape when it reaches a certain point(instead of the gaskets failing) a valve would not allow air in.
And yes there is 98k on my mv6 so gaskets are obviously overdue a change.
Anyway I think most people are misunderstanding what my original post was about. So let's stop going round in circles.
I appreciate all the comments,
Thanks

[chrisgixer]

You should be! The breathers are the only thing that remove the pressure from the crank case. By vacuum from the plenum.

 Drill a hole and you introduce more air than the maf has metered. Fail.

 Fit a pressure relief valve to relieve pressure, then the pressure shouldn't be there in the first place. Your breathers are blocked. Fail.

If the breathers are clear, and it still leaks, gaskets failed.

(Assuming its the cam covers leaking of course)

[Sir Tigger KC]

I think that the OP's suggestion of a pressure relief valve is a good idea to be honest. 

If it was mounted on the cam cover where it is easily visible and you could spot oil weeping from it then you know it's time to clean your breathers.  The advantage is that you havn't blown the cam cover gaskets and saved a lot of cash and hassle!    

Of course no sensible Omega owner would wait for such an event and we all know that if you clean your breathers regularly then you shouldn't have a problem with the cam cover gaskets, but none of us are perfect and I'd wager that most of us have changed the gaskets at some point in our Omega ownership. 

So I don't think it would be a bad modification.  The problem it would seem to me, would be getting a valve that would let go before the gaskets do whilst maintaining an appropriate pressure within the crankcase. 

[dublin.jd]

I think that the OP's suggestion of a pressure relief valve is a good idea to be honest. 

If it was mounted on the cam cover where it is easily visible and you could spot oil weeping from it then you know it's time to clean your breathers.  The advantage is that you havn't blown the cam cover gaskets and saved a lot of cash and hassle!    
 
Of course no sensible Omega owner would wait for such an event and we all know that if you clean your breathers regularly then you shouldn't have a problem with the cam cover gaskets, but none of us are perfect and I'd wager that most of us have changed the gaskets at some point in our Omega ownership. 
 

So I don't think it would be a bad modification.  The problem it would seem to me, would be getting a valve that would let go before the gaskets do whilst maintaining an appropriate pressure within the crankcase. 
[/quote

Finally, someone who understands what I'm trying to achieve.  I'm not looking to bypass the breathers or avoid cleaning them. Just looking for a fail safe.
Thanks again

[dublin.jd]

Finally, someone who understands what I'm trying to achieve.  I'm not looking to bypass the breathers or avoid cleaning them. Just looking for a fail safe.
Thanks again.

Sorry for the repeat, I made a mess of last post.

[Entwood]

I'm afraid I must join the "not a good idea" group on this one ....My reasons are quite simple ... under normal operating conditions, with clean breathers, the sump is kept under slight negative pressure by the vacuum effect through the breather box, this both prevents the CC gaskets "blowing" and ensures that all noxious fumes, oil vapours, blowby gases etc, are returned to the combustion chambers and burned before reaching the atmosphere.

The ONLY ways positive pressure can be achieved within the sump are either loss of vacuum or excess gas inwards. Excess gas inwards would be rapidly noticed by the loss of performance as the engine would suffer a severe loss of compression.

That just leaves loss of vacuum; again.. only two ways for this to occur, actual loss of vacuum from the engine intake; this again would also give a large loss of performance or ... AS IS THE MAJOR OCCURRENCE, blockage of the breather pipes/box that get the vacuum from the intake to the crankcase.

As there should be a negative pressure, even an equal pressure, let alone a positive pressure sufficient to blow the gaskets, is a serious fault and should be rectified, NOT masked by the fitting of relief valves to "limit" the erroneous overpressure.

IMHO the ONLY method to prevent the over pressure occurring is the correct and frequent cleaning of the breather system such that it does the job it was designed to do.

[Sir Tigger KC]

I'm afraid I must join the "not a good idea" group on this one ....My reasons are quite simple ... under normal operating conditions, with clean breathers, the sump is kept under slight negative pressure by the vacuum effect through the breather box, this both prevents the CC gaskets "blowing" and ensures that all noxious fumes, oil vapours, blowby gases etc, are returned to the combustion chambers and burned before reaching the atmosphere.

The ONLY ways positive pressure can be achieved within the sump are either loss of vacuum or excess gas inwards. Excess gas inwards would be rapidly noticed by the loss of performance as the engine would suffer a severe loss of compression.

That just leaves loss of vacuum; again.. only two ways for this to occur, actual loss of vacuum from the engine intake; this again would also give a large loss of performance or ... AS IS THE MAJOR OCCURRENCE, blockage of the breather pipes/box that get the vacuum from the intake to the crankcase.

As there should be a negative pressure, even an equal pressure, let alone a positive pressure sufficient to blow the gaskets, is a serious fault and should be rectified, NOT masked by the fitting of relief valves to "limit" the erroneous overpressure.

IMHO the ONLY method to prevent the over pressure occurring is the correct and frequent cleaning of the breather system such that it does the job it was designed to do.

Sigh.....     

The OP never suggested neglecting cleaning his breathers or fitting something to 'mask' a problem.  He's clearly (to me anyway) stated that he cleans his breathers when he services every 5000 miles.  All he's suggesting is something to save the camcover gaskets should the breathers become blocked.  Which in my opinion isn't a bad idea, as camcover gaskets are expensive and a PITA!

Perceived wisdom here is that you don't fit alloy cam covers and tighten them down, because then the crank seal will go instead of the cam cover gaskets if the breathers become blocked.  All the OP is suggesting is creating a more convenient weak spot than the cam cover gaskets. 

Your last sentence is of course correct Entwood! 

[Entwood]

Sir Tigger .. not going to repeat quote the whole thing as it is a tad pointless.. we can all read upwards ! 

BUT .. again IMHO ... if relief valves were fitted the tendency would be to rely on them ....

sort of .. "I don't need to/won't clean the breathers until the relief valve pops ..." which is inherently bad .. again  IMHO

If this was such a good and practical idea, why haven't the many highly experienced engineers that frequent both here and ABS ever suggested it before The engines have been around 20 years, and doing this to CC gaskets for 20 years (if neglected) ..... 

Not being cynical or awkward .. just my take on the matter

[Sir Tigger KC]

Sometimes the simple ideas are overlooked by the cleverest, but as you say it's a bit pointless arguing about it. 

I just think that most have missed the point of the OP that's all. 

[dublin.jd]

I appreciate everyone's comments. And we all have an opininon for and against. I feel it would benefit me personally and was hoping to get ideas from like minded people. I'm not trying to cause debate (not that there's anything wrong with debating stuff) and hopefully come out a bit wiser. Please stop telling me to keep the set up original as that's what I'd like to improve.

Sir Tigger seems to be the only one to read my post and get what I mean without explaining further.
No disrespect to any other comments.
Thanks all, again

[chrisgixer]

Sometimes the simple ideas are overlooked by the cleverest, but as you say it's a bit pointless arguing about it. 

I just think that most have missed the point of the OP that's all. 

Quite the opposite. The op isn't listening, its a pointless exercise. But its his car, and all that.

You said yourself, how much pressure are we talking? And the gaskets need charging anyway. First rule of modifying anything, get it working correctly, THEN see what can be improved.
Don't start from a failed base line, thus building on a failed principle that can only lead to further .... Oh never mind.

[dublin.jd]

I am listening. People are in too much of a hurry being pessimistic, instead of adding anything constructive. Lets pretend my car is perfect and I want to keep it that way, and also modify the breather aassembly. The real condition of my car is irrelevant to what I'm asking. Please stop nit picking. I'm looking for ideas, not criticism! But if it's constructive, then keep it coming. Obviously not everyone thinks it's a good idea and that's fine. I want to hear from people that agree.
Thanks

[Webby the Bear]

Nice to see our normal smilies back!!

Anyway, I have a question (from a learning perspective, so don't shout at me or I'll get my bear stick out  )

Air is drawn in from the crankcase to the inlet manifold (via the breather system) due to the vacuum created by the pistons going down on the inlet stroke (not the power stroke as both valves are closed).

I presume then that this vacuum on the inlet stroke also acts on the components above i.e. cam covers/gaskets.

SO. Assuming I've got this correct then surely drilling holes will pull more air in from the outside via these holes thus bringing in air that's not been account for by the MAF. This would cause a lean condition, no?

Thinking about Dublin.JD's suggestion of a one way valve... as it's a vacuum and no more air can be drawn in then surely this wouldn't have any effect as the vacuum pressure would still be applied to the CC gaskets?

Again, I'm not arguing with anyone so don't take anything out on me. Just trying to get the process correct in my head