Oil Surge/control Issues Or Catch Can Not Setup Properly?

[No Crust Racing]

CA18 track car, not fast but potentially fast enough to move fluids around too much.

During a hot session where I'm going for it, the car recently filled the 1L catch can twice. I did not put the fluids back in as the dipstick seemed to indicate it had enough in it, but it should not have been overfull as I'd checked it before the track day. I am also finding that it would like to shoot out the dipstick if allowed - I have it wired to hold it shut.

After removing the oil I could hear ticking/rattling in the top end when going hard around corners implying no oil supply to the head/lifters.

I've checked and cleaned the balance tube when it was out last during head gasket replacement.

Both rockers are are plumbed to the can, the can has baffled and vented to atmo with a filter on it. The factory connection back to the intake pipe pre turbo is blocked.

I assume the PCV valve is working properly from the basic rattle test.

I thought perhaps it was just lots of blowby but it comp tests indicate it's healthy (but it is running 17-18psi). I am now thinking it's either not breathing as it should or during hard cornering/braking/accel the oil is loading up one one side and blocking the balance tube or some other form of return.

Thoughts?

[89CAL]

If you are running the catch can to atmosphere you need to block off the PCV

[r33_racer]

If your dipstick is blowing out then you have excessive blow by. So your initial thought was correct, you can ignore the comp test as it wont tell you what's wrong in this situation. Your crankcase is pressurised. Simplest fix is to put a crankcase vent from your sump pan to your catch/breather can so the blow-by pressure can evacuate.

What you could do is put a hose on your dip stick tube and run that to your catch can. That would help and it is pretty easy to do. Much easier then pulling sump off and having a -12 fitting or hose tail welded on.

Edited June 30, 2014 by r33_racer

[No Crust Racing]

It's been suggested I tee into the turbo return for the same reason.

[Badgaz]

If your dipstick is blowing out then you have excessive blow by. So your initial thought was correct, you can ignore the comp test as it wont tell you what's wrong in this situation. Your crankcase is pressurised. Simplest fix is to put a crankcase vent from your sump pan to your catch/breather can so the blow-by pressure can evacuate.

What you could do is put a hose on your dip stick tube and run that to your catch can. That would help and it is pretty easy to do. Much easier then pulling sump off and having a -12 fitting or hose tail welded on.

you have me a little confused...crank case ventilation happens at the top of the motor out the existing breathers....which if they are not evacuating the pressure fast enough could be causing too much crankcase pressure....i'm not sure what or why you would vent your sump....normally that is the return for the oil caught in the catch can.

[KiwiRS4T]

You vent your sump because that is where the crank case pressure is - it blows up the oil drains making it harder for the oil to come down and it ends up blowing out the cam cover breathers.

And no ...do not T into the turbo return.

But yes try a tube from your dipstick tube to the catch can.

I know nothing about CA engines but feel OP would still benefit from reading the last 10 or 20 pages of the oil control thread (on about p3 or 4 of this forced induction section).

[r33_racer]

Pretty much as KiwiRS4T just explained. Virtually all piston engines are the same, work under the same principles and suffer from more or less the same issues when pushed on the track.

I wouldn't recommend teeing in the turbo oil drain also. The oil from the turbo will not actually drain as the joint will be constantly pressurised with venting blow-by. You will end up with oil leaking around the front/back turbo seals.

CA's, SR's and RB's I have seen them all suffer the same blow-by issues at the race track. They can all benefit from adequate crankcase ventilation.

[Badgaz]

You vent your sump because that is where the crank case pressure is - it blows up the oil drains making it harder for the oil to come down and it ends up blowing out the cam cover breathers.

And no ...do not T into the turbo return.

But yes try a tube from your dipstick tube to the catch can.

I know nothing about CA engines but feel OP would still benefit from reading the last 10 or 20 pages of the oil control thread (on about p3 or 4 of this forced induction section).

is there a factory vent from the sump or do you need to drill and tap one? if you use a drain from your catch can it should be below the oil level in the sump to stop it blowing back up.

[Ben C34]

There's heaps of discussion on how and where and why to vent the sump in the oil control thread.

[No Crust Racing]

CA's have a "balance" tube, which goes from head to sump which certainly helps but is obviously not doing enough and the only other connection into the sump is the turbo return.

I'll do some more reading.

[89CAL]

If you are running the catch can to atmosphere you need to block off the PCV

Did you try this.........

[No Crust Racing]

Not yet, haven't had any time.

Apparently I need to un-tee the two cam covers also.

They are currently both connected to the catch can, as is the PCV, can is baffled and vented to Atmo.

The connection to the intake is blocked.

This is all sorts of wrong but I'm not sure what is the best step to take to fix it. And what should be routed where.

Originally I had the intake side cam connected to the PCV as stock and the exhaust side connected to catch can and then vented atmo but it was still filling with oil.

[KiwiRS4T]

is there a factory vent from the sump or do you need to drill and tap one? if you use a drain from your catch can it should be below the oil level in the sump to stop it blowing back up.

No I have two half inch vents both above the oil level. One goes to the top of the catch can and one to the bottom. At WOT both act as vents and when you lift off any oil blown in can drain back.

[No Crust Racing]

Ideally I'd like to solve this issue without adding fittings to the sump.

[Badgaz]

if you vent to atmo you need to make sure your catch can has venting size same as the inlet size e.g 2 x 5/8 fittings for inlet & outlet otherwise your catch can will pressurize. i also tried this system on my car but didn't really have any success with it...

http://forums.vwvortex.com/showthread.php?4387972-Bypassing-PCV-and-routing-to-exhaust-description-(DIY)-(long)

[No Crust Racing]

Ahh I was looking at that Moroso setup.

[Jazzadub]

I hope this isn't a trade secret, but RIPS solution, on my car anyway, is as simple as this:

Two lines from valve cover breathers to top of vented catch can.

Two lines from catch can to sump, above oil level. One line is from the bottom of the can, and one is slightly higher (same as KiwiRS4T)

1.3mm restrictor (IIRC), note I have an RB26 and Tomei oil pump.

No head drains or any crap like that.

I don't think the oil stick tube will be big enough to act as a good breather, but I might be wrong.

Will report back if I have any issues with it, but I think that's unlikely!

[Trex]

Oil control

http://www.skylinesaustralia.com/forums/topic/110680-oil-control-in-rbs-for-circuit-drag-or-drift/

catch can

http://www.skylinesaustralia.com/forums/topic/129549-oil-catch-can-mounting-and-roughting/

Hopefully these can help fix your problems so you can go out and actually have some fun

[No Crust Racing]

OK here's what I've got and what I'm thinking.

How it looks now. Intake pipe is blocked, can is vented to atmo just near wiper motor. Excuse rag, it was put there during the track day.

Everything plumbed to can.

What I'm thinking.

Plumb intake side as per factory (green)

Plumb exhaust to can (green) and would include oil/air separator

Plumb Intake pipe back into can (red)

Plumb can to dump pipe (blue) using one of those one-way valve crankcase evacuation kits.

So it should have vac from the intake and the exhaust under all conditions.

The other option is do the same but plumb the intake side into the can as well and block the PCV.

Thoughts?

Edited July 6, 2014 by ActionDan

[89CAL]

Did you try blocking the PCV off yet