seen a few guys using clear plastic tube for the breathers, looks a bit messy but at least you can see if its blocked i guess
seen a few guys using clear plastic tube for the breathers, looks a bit messy but at least you can see if its blocked i guess
For SRs one of the sensible upgrades is to fit an increased capacity oilpan. I have never seen this for the CAs. Would it help?
I have seen some. They dont cure the problem. If you want better oil starving protection, you need to extend it down, and prolong the oil pickup. If not, you will get oil starves in fast corners, even with a baffled sump.
The oil starvation problem is not due to low oil capacity, it is due to oil not returning to the sump. It does not return because the sump is pressurized. Increase oil capacity and you will just send more oil to your head, but starvation will not be avoided this way. Let the sump breathe, and problem is solved.
Agreed with croustibat. Since I have done the oil return mod, and modified breather pipe, plus adding a CA16/CA18DE head breather, I didn't have any oil starving problems, during heavy acceleration/cornering, or any else engine abuse.
Last edited by kalin; 03-09-2009 at 19:48.
but blow by past the rings is the root cause of crankcase pressure.
As external breather is quite restrictive some of the blow-by must go up the oil drains, they don't have a mesh or 2 90° bends but do have small holes in the gasket. So it could blow oil back to the head. But at worst blow-by condition the breather system only breathes though the hose to the AFM trunk and that has a slug of metal with only a small hole in it. It's very much smaller than drains + breather so the head will run at about crankcase pressure, reducing flow rate of blow-by from crankcase. The better you let the head breath the worse the problem as it promotes flow of blow-by up the drains. (Kalin's mod has effectively made the drains into breathers and put new drains in)
BE failure has occurred on stock engines, so it's back to poor oil change intervals / thrash from cold and blocked breathers are a symptom not a cause.
Slyshack - I've never thought of it that way around before. I currently have the cam cover breathers both connected to a single cusco catch can, which then vents to atmosphere. I no longer have the hose that goes from cam covers to pre-turbo.
Due to the fact that I have taken out the cam covers -> pre-turbo hose that has the integrated restriction - do you think I will not be letting oil drain back to the sump as much as desired; due to head pressure being much less than crankcase?
This info kind of contradicts what your saying, although your making more sense to me than this other info from GG:
http://www.grahamgoode.com/breath.htm
As explained above, most of the pressure is created in the cylinder block by piston ring blow-by. If the engine is vented from the top, the rush of crankcase pressure to the top of the engine will prevent the oil fed to the cylinder head from draining back into the sump. Admittedly, the oil vapour is more dense in the bottom of the engine, this is why we have the oil / air separators.
Last edited by liquidsmoke; 04-09-2009 at 16:03.
Hi guys i have an s13 which has had one owner from new and done about 100k now. I have covered about 3000 miles in it now and done about two oil changes. The oil gets very dirty very quickly. anyone know why this might be.
I want to try and take care of this engine and want to avoid starvation when going sideways. does anyone have any pic of the breaths i need to clear out and to help me better understand which ones they are and where they are?
This is the breather that causes most problems, the metal one with the right angle. Very difficult to get to with the inlet manifold in place.
The oil probably gets dirty due to the amount of blow by from tired rings. A decent quality rebuild can be done for not much more than £500.
The only source of "dirt" in an engine oil system is carbon from blow by.Originally Posted by cleanhands
A taxi engine will last forever in that worn state. In a sports car that is used to the limit it will die.
Just want to put my pennies worth here, my car has done just over 100k with the original engine, It's was running stage 3 at 290bhp fine for a majority of that time, I am the third owner and the car has all service stamps in the book etc so has been well maintained engine wise
I've recently removed the engine because I have a forged one I am building to put in (more ponies!) I decided to have a look at the original engine and strip it down to see if there was any "coking" / "Black Death" lurking anywhere and there was absolutly feck all, the engine has no signs of wear at all, was quite shocked to be honest
All this talk about CAs having bad bottom ends is bull poo, you can't expect to jump in a car that's 20 odd years old and thrash the shit out of it non stop and expect it to be fine about it, it's so called "drifters" that have dubbed this engine as "having chocolate bottom ends"
Babbled on a bit here.... I'll stop now
EDIT: Oh.... Just realised how old this thread is and it's a new question being asked, it's late
Last edited by maff_1991; 16-02-2014 at 01:36.
Agreed CA's get a bad rep, and don't worry 3 other posters bumped the thread ,,,only 4 years 6 months and 3 weeks
As for oil starvation. MB have had trouble on V8's. The oil that would normally be expected to flow DOWN the slope of the head wasn't, on fast long turns it was flung UP the slope of the inside head and refused to go down the drain at the bottom. Outside head is OK but becomes inside on opposite turn.
So half the issue could be the direction that drift events are run and number of right handers. Most motor circuits are run clockwise, that means there is 360 degrees more left handers than right. Engines are designed and oil drains fitted for that - even on "street" engines, as that's how it is done. Left handers return oil to the exhaust side drain, right handers fling it up the slope away from the drain. Right handers on motor sport circuits have to be short kinks or a hairpin that don't last long. There isn't much of a "drain" on the inlet side, more like a vent at front "uphill" end.
Longitudinal acceleration, braking is short and hard the oil will flow to the front of the head, acceleration is less but lasts longer so oil moves to the rear of the head - where there is a drain on the exhaust side.
Increased volume, hinged trap doors and additional oilreturn.
Shogun that sump is exactly what I've been thinking about.
From where do you connect the oil return lines? You have at least 6 new return lines on the sump...do you have one coming from the rear of the head? Where else do you recommend?
Last edited by Ronny-CTS; 16-02-2014 at 16:55.
190k miles and still going strong here, love my ca's always have always will. Such simple engines to work with just keep them maintained and topped up with oil and they will last. At least in my case 2 ca's have and my 1 sr didn't
Two return lines from the back of the head. Another from the turbo and a couple of spare ones for catch tanks or equal.
Here you'll have a good read
http://www.sxoc.com/vbb/showthread.p...=ca18det%20oil
Thanks....Just one question, are you venting your sump directly to an oil catch tank and consequently to the atmosphere? In order to decrease sump pressure?
Last edited by Ronny-CTS; 17-02-2014 at 11:19.
Big ends going may also be partially due to poor mapping or modifications without an appropriate map... I've heard that det can kill CA18DET big ends. I'm not sure it totally makes sense, but apparently it adds a lot of pressure to the bearings at a particular angle where it the load isn't spread (over time, I guess?).
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