Rocker cover breathers advice needed

[dom123]

i want to install 2 breather ports in my rocker cover, one over each cam, i want to do them aeroquip, whats the best way about doing this?

i'm fed up with leaky rocker covers, ive tried every different method of sealing them up... ive done this job over 5 times now, from my findings if i drive the car under 2 bar boost they never seem to leak, as soon as the boost is over 2bar sudenly there leaking again, i'm convinced there is to much air pressure in the top of the engine...

my friends rb26 has twin breather set up standard he has no problems so i'm thinking there is a need for it.. surely with breathers at the top of the engine it should stop the air pressure build up which pushes the oil through the cam half moons seals... what aeroquip size is the oil breather system?

cheers

[Kelv]

if you run a decent breather setup, then you shouldnt be breathing from the cam cover anyway but one from each side of the block.

[fordrallycar]

Oil breathers use -10 hose you drill & tap the cover or weld fittings on to the cover & use goodridge fittings

[dom123]

i am runing a breather system which is breathing from both sides of the block. i think the cams make so much air movement up the top which causes the problem... i dont understand how the bottom breathers would help this what so ever..

mines a small turbo type rocker cover, but aparently the metal there mad of is terible for welding... has anyone welded a boss into one of these covers?

[richyx]

you shouldnt get any pressure up there tbh as oil breathers are designed to release crank case pressure, as this pressure is caused by blow by past the rings, obviously more boost more blow by more crank case pressure, alls you should need is it to breath both sides of the block and a return to sump and id say one to atmosphere just to get rid of the pressure and mositure but not the oil

i wont ever breath from top of cam cover again as it just causedme more problems when going on full boost as it created a vacum and sucked the oil out my head and spat it into my catch tank

[dom123]

you shouldnt get any pressure up there tbh as oil breathers are designed to release crank case pressure, as this pressure is caused by blow by past the rings, obviously more boost more blow by more crank case pressure, alls you should need is it to breath both sides of the block and a return to sump and id say one to atmosphere just to get rid of the pressure and mositure but not the oil

i wont ever breath from top of cam cover again as it just causedme more problems when going on full boost as it created a vacum and sucked the oil out my head and spat it into my catch tank

thats odd problem mate as nearly all the saphs and bt engines have a breather in the cover with out the problem your describing.. surely if the block breaths all the movement of air from the crank whats breathing the movement of air that the cams produce..?

[Ben Purnell]

have a look here, should answer a few questions
http://www.grahamgoode.com/breath.htm

[Kelv]

its because all of the cheaper breather setups (ie: Bailey) fit them that way, more so for ease and for a cheap manor.

breathing from the cam cover is certainly better than no breather atall, but if there is a choice then you should breathe from either side of the block and leave the cam cover alone.

[rsnissan]

thats odd problem mate as nearly all the saphs and bt engines have a breather in the cover

have you got any pics of these breathers that connect to the cam cover?

[dom123]

ive just had a read, but common sense to me makes me think the more breathing holes the less the internal pressure will be...

heres a pic of the rb26 rocker cover design

[Kelv]

that picture highlights what i said, the cheaper breather systems!

[SCS j1mbo]

im with kelv, we never use rocker cover breathers,

breath from the kindey can, or just the block where the kidney can goes and then turbo side as the back of the block it should be fine, make sure the return is below oil

where do you breath from now ??

[dom123]

i currently already breath both sides of the block and already drain to sump and have a port to atmoshere... but i'm thinking about tapping the rockercover with two m14 threads one over each cam and then fit 2 an-10 to m14 male to male adaptors, then run the 2 hoses off the cover to a y peice to convert to single -10 then weld another port into my breather and fit it on....

so at scs you dont have rocker cover leaks?

kelv i have a cheap bailey breather but ive plumbed it in the proper way... i'm talking about have a mate weld a extra port on the side of the bailey pot not adjust so it works like the cossie in the pictures above...

[Ben Purnell]

do you get the gasket and half moons from Ford

the ford rocker cover gasket was much better than any in the local part places

[SCS j1mbo]

i currently already breath both sides of the block and already drain to sump and have a port to atmoshere... but i'm thinking about tapping the rockercover with two m14 threads one over each cam and then fit 2 an-10 to m14 male to male adaptors, then run the 2 hoses off the cover to a y peice to convert to single -10 then weld another port into my breather and fit it on....

so at scs you dont have rocker cover leaks?

kelv i have a cheap bailey breather but ive plumbed it in the proper way... i'm talking about have a mate weld a extra port on the side of the bailey pot not adjust so it works like the cossie in the pictures above...

not on a new build no, when the engine is old then they can leak yes, but like i say, we never run them on top, unless, the customer has it on there and wants to keep it,

where is your drain to sump, above or below oil level ?