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[aoliver]

Seem to feature a lot on this site mainly due to the former blocking and problems with changing he latter as a result. What do the experts think of the idea of drilling a small hole in each camcover and blocking it with a grommet ?. Then, should the breathers block, the grommet would blow out rather than the camcover seals resulting in a much simpler repair job.

[mantahatch]

Hi
At first thought it would appear to be a good idea, I wonder where the best place to put the grommet would be, and how big it would need to be, and how tight a fit to stay in place and only blow out when the breathers are blocked.

Regards

Mike

[FRE07962128]

Seem to feature a lot on this site mainly due to the former blocking and problems with changing he latter as a result. What do the experts think of the idea of drilling a small hole in each camcover and blocking it with a grommet ?. Then, should the breathers block, the grommet would blow out rather than the camcover seals resulting in a much simpler repair job.

How will you guage the size of the 'blow holes' in relation to the natural pressure v. the extreme pressure build up when the breather is blocked? : :-?
I can see a problem in ensuring the grommets size is balanced just so for perfect non-operation when under normal pressure, and blowing when excessive.  Or am I being too complicated?

Lizzie Zoom

[mantahatch]

As a further idea, why not go down the old route of running a pipe from the cam covers to atmosphere. I no it is not entirely enviromentally friendly but this government has done me no favours so why not.

Mike

[aoliver]

Good points. I've no idea of the pressure in the camcovers during normal running, I can only assume it's fairly low if they can get away with making them out of plastic. I'm guessing a push fit into an 1/8" hole would be enough, but hopefuly someone with considerably more knowledge will be along in a minute.Regarding Mike's post above, I've just looked at my other car ( 2001 Caterham 7) and that just has a couple of pipes running from the camcovers to a catchtank, and no problems with blown camcover seals.

[Kevin Wood]

As a further idea, why not go down the old route of running a pipe from the cam covers to atmosphere. I no it is not entirely enviromentally friendly but this government has done me no favours so why not.

Mike

The problem with this is that it will result in a leak of unmetered air into the engine if the original breathers aren't removed.

Keeping the breathers clean and not letting the oil get into a filthy state is probably all that's required to prevent the covers going, TBH.

During normal running the cam covers will have a slight vacuum under them, since the breathers are fed from the plenum and intake tract.

Kevin

[FRE07962128]

Good points. I've no idea of the pressure in the camcovers during normal running, I can only assume it's fairly low if they can get away with making them out of plastic. I'm guessing a push fit into an 1/8" hole would be enough, but hopefuly someone with considerably more knowledge will be along in a minute.Regarding Mike's post above, I've just looked at my other car ( 2001 Caterham 7) and that just has a couple of pipes running from the camcovers to a catchtank, and no problems with blown camcover seals.

I don't want to appear negative to these ideas, but won't open 'blow pipes' upset the pressure balance of the engine? :-?

Lizzie Zoom

[mantahatch]

As a further idea, why not go down the old route of running a pipe from the cam covers to atmosphere. I no it is not entirely enviromentally friendly but this government has done me no favours so why not.

Mike

The problem with this is that it will result in a leak of unmetered air into the engine if the original breathers aren't removed.

Keeping the breathers clean and not letting the oil get into a filthy state is probably all that's required to prevent the covers going, TBH.

During normal running the cam covers will have a slight vacuum under them, since the breathers are fed from the plenum and intake tract.

Kevin

You are right Kevin, you must excuse me I am from the old school of keep it simple, and forgot that it actually needs to be attached to the plenum.
I suppose the only way round it would be to do away with the existing breather system entirely, oh god now I am dreaming, talking rubbish.

I will get my coat

Mike

[aoliver]

Open breather pipes clearly don't upset the "pressure balance" of a Caterham engine but Kevin's post would indicate this may be different with an Omega. However, if the camcovers run at a slight negative pressure, the blanking grommet would be an even easier solution. I agree with the point that clean oil and breathers is the best preventative maintenance. I change my oil regularly but the breather cleaning seems a lot of faffing about to do unless you have to.  

[Kevin Wood]

You are right Kevin, you must excuse me I am from the old school of keep it simple, and forgot that it actually needs to be attached to the plenum.
I suppose the only way round it would be to do away with the existing breather system entirely, oh god now I am dreaming, talking rubbish.

I will get my coat

Mike

No need to excuse anything. My "other car" has an "old school" breather setup. Can't see a foot and a half of heater hose from the catch tank to just above the tarmac blocking in a hurry!  

I guess the main disadvantage with open breathers, apart from the environmental, is that they don't give a constant ventilation of air through the crank case, they just allow for expansion and for fumes to escape. That would mean more problems with condensation on short journeys, and the need for more regular oil changes due to contamination.

Kevin

[aoliver]

Would anyone happen to know if each camcover contains 2 seperate sealed chambers or one ?

[albitz]

i would imagine some sort off pressure relief valve could work,  but you would still have to work out what pressure the valve needed to open at  :-/

[Kevin Wood]

I would have thought it would take very little pressure to blow a cam cover gasket. There's a lot of surface area on the cam covers and they are plastic. Wouldn't take much to lift the edges just enough to relieve the clamping pressure on the gaskets.

Kevin

[aoliver]

I think you're right. In that case surely an 1/8" hole covered with duct tape would be enough to save your gaskets if the breathers blocked.

[VXL V6]

Prevention is always better than the cure.... Clean the breathers and change the oil regularly and any other modification is redundant IMHO.