Mark-32

Thanks for your input mate. Sounds like we are running a similar sump as thats the same reason that I put my fitting on the driverside aswell. On a positive note I got the good news yesterday from the leak down test and compression test. Havn't got the results in front of me as im interstate but the workshop said its got a good seal and it showed there is next to no blow by what-so-ever. Big relief to say the least. It still bloody amazes me that a 1.5 restrictor can pump so much more oil than the 1mm one though.... Especially since I have the spring removed from my nitto pump.. Do people think I should refit the spring to my oil pump when I have the engine out? And also maybe run the 0.9mm restrictor???? The workshop said although 120psi is a tad high when both springs are in place I shouldn't really run under 90 odd psi oil pressure to keep the engine alive. Without the spring fitted Im only geting 75psi or there abouts.

No mate the head is draining into the driverside of the sump, so that could also be my problem

Im hoping your not riight but I have a bad feeling you may be. The engine was assembled by the same place that did the machine work and ballancing to avaoid that problem. The one thing that does make me think it may be blow by is when I first drove the car after the dyno run, smoke was starting to appear inside the cabin when reving out in 4th gear. At that time there wasn't a decest catch can in place so the small amount of smoke/oil was coming out the rocker hoses and spraying onto the hot engine block. I lined up a leak down test for it later this week so we will know soon enough.

Had to hit the firewall in with a large hammer to make it clear the firewall. The car is in the north. I was in Tas this weekend for a wedding but didnt have any tiime to tamper with it. I havn't taken the car to any workshops down there yet except brad sherrif for one run to make sure it was sweet after we refitted the head. One thing I did notice was the power steering belt was half off the pump pulley. There was also no oil in the can after I went for a drive around the block. It didnt blow any oil into the can when it was on the dyno either, Its only when drifting doing big revs for a constant period of time, and the smokey exhaust. is a new thing it had never done that before.

Yeah I have spoken to the engine builder and he said run a leak down test and a comp test which is whats next. He assures me the clearances will be spot on but to do the test anyway to be 100%. He has helped me out with warranty no questions asked and has alot of years of experience with rb26/30 engines. He was abit baffled after all the oil galleries in the head had been opened up, Nitto pumps were relatively new then and they mostly ran the n1 oil pumps with the jpc gears. The engine was run in on a dyno under load and I have done a comp test on the engine previously aswel that came up fine.

So do you think its worth my while doing a leak down test on the engine before I pull anything apart? You have no idea how frustrating this is, and what makes it worse is the car is in Tas and i currently live in NSW. Heres a couple of pics of the setup.

Yeah thats what I thought. So lift the head fitt the 1.1mm and go from there! Thanks for the input.

Thanks for all the info that was very helpful. It gives me a couple of things to try help fix the problem before I go ahead and remove the engine from the car. Two things I will try are the crossovver pipe between the rocker covers, and also swapping my rear head drain from the drivers side of the sump into the rear turbo oil return pipe that goes into the block. That way I can use the fitting that goes into the driverside of the sump as a breather that runs to a baffled catch can Surely If you get to the point of having to use scaverger pumps to return oil to the sump then the wrong size restrictor is being used, either that or you have way too much oil pressure? I mean you mentioned only running the 1.5 restrictor with the nitto pump, I realise that you also stated all the other oil return mods to but if im having these problems with the 1.5 restrictor and no spring in the nitto pump surely your going to be worse? I just dont see how its healthy to have that amount of oil in the head for any preiod of time even if there is still enough in the sump to keep the bearings alive, especialy when the head gets that full to the top of the rocker covers to the point that it overflows out the rocker covers by the litre. The smokey exhaust surely cant be a good thing either? As I said before I would really like to avoid pulling the head off the engine again if possible as it means removing the entire engine from the car. I surpose Im hoping that someone tells me that amount of oil in the head is fine, dont worry about the smokey exhaust, just fit the nismo seperator and another catchcan with the drain to the sump and drive it. I know that setup is far from ideal but surely if people are resorting to scavenge pumps and things then my setup would still work fine until I get around to lifting the head and replacing the restrictor? The car will not see any WOT for long periods of time, only short runs drifting and when on the dyno adding boost.

How did you drop pressure though? Im hearing what you saying but I really dont want go ahead and lift the head and fit the 1.1 restrictor only to find I still have oil in the catch can once its up and going. In saying that though i also dont want to fit the 0.9 restricctor to find im starving my top end of oil, especialy seeing that I have removed the spring fromm the oil pump. The guys at envy spin their engines to 10,000rpm, dont remove the spring from the nitto pumps and have zero oil in the catch can with the 1.1 restrictor in place. That makes me think maybe I should refit the spring in the pump and run the 0.9 restrictor? Jim at croydon said that I shoudnt have removed the spring from the pump either and that the 26 engines need every bit of the 125psi oil pressure that the pump provides. I dont want to drag this on but I also want to get it right so I can wind the boost up on the bloody thing and drive it.

Made a few calls today, first off I spoke to Jim at Croydon as they were the guys who supplied me the engine hardware. They said that its normal for the engine to be blowing oil into the catch can and I just need to fit a proper catch can with return line into the sump. He said If i fit a smaller restrictor it will make bugger all difference to the amount of oil entering the head. I reckon thats bullshit!! I then rang envy here in sydney and told them about my setup and as Beer Baron said they certainly know there stuff. They said that its strange im having these issues at only 7800rpm and that they are using 0.9mm retrictors on there engines and are now even going to 0.7mm restrictor. All in all this is a huge headf@ck

Thanks for your help mate. First things first i will put an oil pressure gauge on the car and do a leak down test for good measure.

Use the 26 engine loom obviously but there is a plug on the rb26 loom near the air flow meter plugs that needs powering up. This caused me lots of problems when we got mine going as on the gtr's that plug continues around the front of the car round to the driverside battery area.

Thanks for the info. Scavenger pumps and one way valves just seem like the pump must be working too hard. So how much oil pressure should i be aiming to run to keep the engine alive? If the pump is running extremely high oil pressure I may be able to fix the problem whilst leaving the engine in the car, just removing the sump and not the head? It all just seems weird to me as today I spoke to 2 different people who both run nitto pumps, they both even left the spring in when fitting there pumps had the exact same problems as me. They then removed the spring to lower the oil pressure and now they dont get any oil in the catchcan at all and thats with the 1.5mm restrictor in place. Neither of them have an external oil drain or inlarged oil returns either Also, Can i re-use a metal layer head gasket a second time around? This will be the second time lifting the head since the rebuild using the same 1.2 nitto head gasket? Cars and bloody money

Is it a bad thing having that much oil running around in the head and rocker covers full to the top, the head would have to hold 3-4 litres of oil so that would still leave 7 litres in the sump? Im only asking as really dont want to pull the head off it again, but also dont want to get it if its a band-aid fix sort of thing.

So the oil air seperator and nothing else???? Surely if i did that alone its not actualy fixing the problem of the head being overly full of oil though?

So I fitted the mines baffles friday night hoping to fix my issues and took the car to a drift day on saturday only to have the same problems. After doing two laps in the car my fuel pump shorted out due to a broken fuel tank baffle, then after finally fixing that problem I took the car out to try again. To start with the car was blowing alot of white smoke out the exhaust on idle and acceleration, It had never done this before and I have no idea why it happend as my catch can is vented to atmo. Then after the smoke cleared, I did another lap at high revs in 3rd gear and then came into the pitts to find the catch can full of oil, Can anyone fill me in on exactly where I go next with this? Like what size restrictor I need to be using, as obviously the head is going to have to come off yet again, And also why the car would have been blowing the smoke like it did. Im confident the piston to bore clearance is right but im also really hoping its not due to oil passing past the rings as i spent a shitload doing the rebuild and had it done by a highly reccomended workshop in vic with heaps of RB experience. From my understanding the only way oil can enter the exhaust is from the combustion chamber?

My mines rocker baffles turned up today, but I have one last question If anyone can help me try solve my oil issues before I take my car to the track again on the weekend. As I stated earlier, my external oil drain hose runs from the rear of the head to the driverside of my sump. I know its on the wrong side of the engine but I didnt realise I had it wrong until it was too late. Anyway....My question is- if the car still blows oil into the can after I install the baffles, could I cut my oil return line low down near where it bolts to the sump and fit a T-peice in line into the hose, then run out of the t-peice up to my catch can and use this as an oil return from my catch can? Or because its on the wrong side of the sump to begin with will this cause the crankcase pressure to exit via my catch-can and not the head and possibly make matters worse by breathing heavily into the catch can? Hopefully the mines baffles fix the problem but any other help or advise is much appreciated, I've thrown a few dollars on the drift day coming up on the weekend and really dont want the oil issues to wreck my day.

Hi mate, my engine only blew oil into the catch can after doing 2 full laps at WOT around a circuit that took 1min roughly per lap. So its not all that bad, Im entering the car in a drift day next weekend but im going to fit mines style rocker baffles and hope for the best. Im just hoping that because drifting is not constant WOT lap after lap it may give the oil enough time to return to the sump on the half lap of cruising back to the start line!

How much for the autech cans?

Sorry to bring back this topic, but after speaking to a tuner today that knows a fair bit of oil control issues in rb's, and also runs a nitto pump in his race car, i just had a few other questions relating to the nismo style oil / air seperators and oil return. Seeings have my external oil drain from the head plumbed into the driverside of the sump. My tuner said this would be flowing minimal oil down it once tthe head is full of oil due to the way the crank rotates and oil could possibly be blowing up that pipe into the head when pulling high revs for a while. Just have a few questions about my setup if anyone can fill me in. Regarding the nismo style catch can that was pictured, do the rocker cover breather pipes run into the cylinder on each side, then the lower outlet pipe acts a return and just drains back into the engine via the rear turbo oil drain on the side of a block?. Also, will I still need to fit the mines style rocker baffles to the engine? Will another pipe coming off the oil/air seperator then run into a larger normal style catch-can that vents to atmo and that has a return line from the catch can that T's into my current oil drain from the head into the driversside of the sump? Sorry for all the questions just wanted to understand how that setup works and know others thoughts so I can solve this issue permanenttly without pulling the head off again. Not keen to buy things if its just overkill.

It has a 1.2 restrictor fitted. And we also removed the spring in the oil pump to lower the oil pressure. I just thought with all of this done as reccomended here in the rb oil guide section that everything would be sweet. I thought wrong

Would I be right to just fit a different catch can that has a return oil line going to the sump? I could tap into the oil return line from the head and just fit a Y peice into the sump

Its running to atmosphere and it actualy blew a fair bit of oily vapor out the actual filter attached to the catch can.

Just after some feedback on my setup after taking the car to the track for the first time with the new engine. The engine is rb26, -5's and support mods. Oil mods are, Nitto oil pump, Enlarged oil return holes in block, rear external oil drain to sump, custom 10 litre sump, tomei oil restrictor in block. The engine is less than 500kms old and it has good internals Took the car to a supersprint on sunday and the engine blew about 500mls of oil out the breathers into the catch-can. The rocker covers only have standard baffles.

Had to pull up an old one to see if that valve ever worked?