4AGE bluetop filling head with oil - solved

[pc]

I have recently run into a problem after resealing my oil pump and replacing oil seals, where at high revs throttle lift-off oil is sucked through the breather into the intake.
I am assuming this is because the head is now filling with oil at high revs and not draining fast enough, which may be due to the oil pick-up being sealed better now?
This isn't a problem while driving around at normal road driving revs, but when racing the smoke screen created by the oil going through the intake looks like the engine has imploded.

Has anyone had this problem on a bigport and managed to fix it well? At this stage I have blocked up the hole on the intake and routed the breather on the cam cover to a catch can, and then vented the catch can. This produces oil smells and vapour/smoke etc. but allows me to race without sucking all the oil out of the engine in one run.

I am currently thinking about putting an additional external oil drain from the head. Possibly similar to the smallport (but I haven't seen one yet).
Has anyone done this?

[~SlideWays~]

Can't really help with a solution, but this is what caused my turbo to fail at manfeild months ago. I didn't pursue fixing the bigport drain back though, in the end I've went for a smallport/external drain.

Mine filled half the catch can after only 2 and a half stints on the track (its only a 1L though).

Weird that it has just started happening on yours, I thought it was a factory feature.

EDIT: welcome to come have a look at my smallport external drain if you like.

[Stealer Of Souls]

Info's a bit third hand, but I know someone who knows someone who did an external drain... and apparently it was a total pain in the A to do.
It sounds like something is making your problem extra bad. Are the drains in the head particularly scummed up perhaps?

Perhaps run a thinner oil????

[pc]

Info's a bit third hand, but I know someone who knows someone who did an external drain... and apparently it was a total pain in the A to do.
It sounds like something is making your problem extra bad. Are the drains in the head particularly scummed up perhaps?
Perhaps run a thinner oil????

Blocked oil drains was the first thing I checked. The head is surgically clean and I can shine a torch down the holes and see nothing. Also the oil is magnatec and was brand new.

[92mr2paddy]

if you got a oil cacth can then it couldnt suck it through into the intake, but then again you catch can will fill up if its not draining away fast enough,,
mmmmmm

[big_boy]

what about get a catch can put a hole in the bottom & back in to the sump with a one way valve

[Mr Revhead]

how about pulling the cam covers off to see if your head is ful lof gunk, gunk can stop it draining back

btw the bigports are well known for filling the head up, hence the small port drain and 20v bigger inhead drains

[~SlideWays~]

how about pulling the cam covers off to see if your head is ful lof gunk, gunk can stop it draining back

btw the bigports are well known for filling the head up, hence the small port drain and 20v bigger inhead drains

Would it be an option to file out the holes to increase flow back to the sump?

[Mr Revhead]

need to be drilled, and maybe block to match, i dunno.
which means pulling it apart. would need to chamfer them as well

[jondee86]

It would be kind of unusual for the breather to vent directly into the
intake manifold. Usually they vent into the ducting upstream of the
throttle butterfly, so high rpm shutoff will not draw anything from the
cam covers. Venting straight into the manifold will cause your engine
to idle funny

Cheers... jondee86

[pc]

how about pulling the cam covers off to see if your head is ful lof gunk, gunk can stop it draining back
btw the bigports are well known for filling the head up, hence the small port drain and 20v bigger inhead drains

The head is surgically clean and I can shine a torch down the holes and see nothing.

It would be kind of unusual for the breather to vent directly into the intake manifold. Usually they vent into the ducting upstream of the throttle butterfly, so high rpm shutoff will not draw anything from the cam covers. Venting straight into the manifold will cause your engine to idle funny
Cheers... jondee86

Hmmm... I wonder how the intake manifold is plumbed internally, maybe something is broken in my throttle body.

[Mr Revhead]

pcv valve?

[Stealer Of Souls]

Another thought...
What car.
What engine.

When I got a 4AGE in my AE85, it was from a FWD car. And what had happened was that a FWD throttle body was used. The original breather hose went from cam cover to manifold (a RWD manifold). But at the manifold it actually went (internally) along the side to the throttle body. There is a hole in the throttle body assemble on the "outside" of the butterfly. But on the FWD the hole is on the other side of the throttle body. Soo. The breather was actually blocked.

The result was enough pressure in the system to actually force oil into the cylinders during high RPM.... This resulted in burning oil and even when I solved this it had done some permanent damage and my engine would always burn oil quite badly...

I hope I've explained that correctly...

[ChaosAD]

Yea,the pipe goes from the cam cover to the manifold then is plummed internally to just in front of the throttle flap. which is why there will be heaps of oil in the front of the t/b.

[jondee86]

Got a good pic here of how one guy fitted an external oil drain....

http://www.toymods.net/forums/showthread.php?t=7537

I never had the problem, but I'm told that continuous high rpm's
(especially while cornering) can push oil out the breather. It will likely
still end up getting into the manifold and burned

Cheers... jondee86

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[AE25]

like stealer of souls says... definately a breather line thru the inside of the intake plenum that directs blowby oil/air to in front of throttle body. (fwd and rwd throttles have hole on opposite side)

another solution... buy a 2ltr catch tank with internal baffling, an outlet at the bottom that drains oil back to a fitting plumbed into the sump (like a turbo oil drain) and another outlet at the top (that passes thru a filter/baffle back to the intake plenum to burn off the fumes. it is a closed system which wont overflow or give off emissions.

[Mr Revhead]

i realised last night that 4ages dont have pcv valves

[AE25]

20v does

[RedMist]

My race bigport ran two very large vents (one from each rocker cover) through to a catch can. Apparently (do not quote me on this) the relief of pressure allows the oil to drain back quicker (although I cant see how) It seemed to work on my bigport, I had very little oil collected.

[2LTR Rona]

My race bigport ran two very large vents (one from each rocker cover) through to a catch can. Apparently (do not quote me on this) the relief of pressure allows the oil to drain back quicker (although I cant see how) It seemed to work on my bigport, I had very little oil collected.

Have experienced exactly the same with the KE25 that has the same setup, also running bigport as well. I just need to solve the sump leak to stop the oil getting to "L" for leak