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You seem to be trying your best to solve this issue, you have had many theorys and solutions put forward to you that may or may not help but still no cigar as yet.

I can't help thinking that you might not have an oil presure or drainage problem but maybe a high crankcase pressure problem, you have a new built engine but don't take that for granted, if it hasn't got a good piston ring to bore seal or you could be chasing your tail.

I'm not saying that this is the case with you and I hope it isn't, is your engine builder helping you with this? I'm sure you paid him lots of money so he should be finishing off what he started in my mind.

Anyway good luck and I hope you find the answers in the end.

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.

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post-71053-0-45611200-1301210082_thumb.jpg

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Where is the car, north or south? who's doing the work?

I would do everything you can (leakdown test, plumbing etc) before you go pulling the engine again...

I'm suppried the head drain elbow fitts between the head and firewall... that sucka's out there.

Cheers

Justin

Most people run high volume pumps because they're stronger and seem to suffer less failures.

I,ve been using an rb26 for drifting for the past four years and haven't had any trouble with oil in the catch can. Never tried a restricter bigger than 1.2mm and thats the only real difference be can see unlees you've got alot more blow by. I only have standard sump baffles also.

sorry, ment to say standard cam baffles not sump, sump is Hi- octane.

You seem to be trying your best to solve this issue, you have had many theorys and solutions put forward to you that may or may not help but still no cigar as yet.

I can't help thinking that you might not have an oil presure or drainage problem but maybe a high crankcase pressure problem, you have a new built engine but don't take that for granted, if it hasn't got a good piston ring to bore seal or you could be chasing your tail.

I'm not saying that this is the case with you and I hope it isn't, is your engine builder helping you with this? I'm sure you paid him lots of money so he should be finishing off what he started in my mind.

Anyway good luck and I hope you find the answers in the end.

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.

Where is the car, north or south? who's doing the work?

I would do everything you can (leakdown test, plumbing etc) before you go pulling the engine again...

I'm suppried the head drain elbow fitts between the head and firewall... that sucka's out there.

Cheers

Justin

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.

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.

Before you spend $ on anything else, Definetly!!! there are a few variable's involved etc...valve seats and seal, head gasket, sparkplug threads etc etc... but I'm tipping a leak down test will give you a pretty good idea were you stand as far as blow by goes.

Your engine would have been built by an engine builder and machined buy someone else, did they use a torque plate? is the bore perfectly round? what's the tolerances? all this can vary from the top of the bore right down to the bottom, how much Psi? (Too many questions to ask)

There can be no F..ck ups with an RB26, small in cubes, high in power and force feed.

The engine has carbon steel metals, alloys, cast and forged materials with different expansion and contraction rates, best to do a leakdown test when the engine is as warm as possible.

I had a similar problem with a new built engine, it had an oil restrictor, oil drain back kit, N1 oil pump etc etc... same problem, it was found to have a poor piston ring to bore seal, the bore to piston clearance ranged from .004 to .0075 of an inch in the same cylinders, it also needed the catch can replumbed.

The engine was fully rebuilt by Nizpro (a well deserved plug) an re-machined, it still has an oil restrictor, now has a Tomei oil pump, standard cam baffles, no oil drain back kit, this was thrown in the bin, no more problems at all!!!

Like I said, I'm not saying this is your problem but it's definitely a possibility, do a leak down test for sure! and have the catch can plumbing checked just in case. thou it looks ok. Cheers.

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.

Ha ha ha... I thought as much (hammer installation)

If you need somone reliable to leave it with, that won't cost you a fortune- Mobile mechanics/Marty- in Moonah (Hobart) is a good bloke and is used to working via remote (I left my 32 gts-t with him all last year for an engine conversion etc as I work overseas). Brads a top guy- expensive though.

If the belt is comming off, your PS pump isn't straight.

What turbo's are you running? If they're bb are you running restricters? Either that or your valve stem seals are leaking badly... bypassing some combustion pressure into your rocker covers causing you some serious pressure problems? They're cheap, so it might be worth changing them just incase.

GL

Justin

Before you spend $ on anything else, Definetly!!! there are a few variable's involved etc...valve seats and seal, head gasket, sparkplug threads etc etc... but I'm tipping a leak down test will give you a pretty good idea were you stand as far as blow by goes.

Your engine would have been built by an engine builder and machined buy someone else, did they use a torque plate? is the bore perfectly round? what's the tolerances? all this can vary from the top of the bore right down to the bottom, how much Psi? (Too many questions to ask)

There can be no F..ck ups with an RB26, small in cubes, high in power and force feed.

The engine has carbon steel metals, alloys, cast and forged materials with different expansion and contraction rates, best to do a leakdown test when the engine is as warm as possible.

I had a similar problem with a new built engine, it had an oil restrictor, oil drain back kit, N1 oil pump etc etc... same problem, it was found to have a poor piston ring to bore seal, the bore to piston clearance ranged from .004 to .0075 of an inch in the same cylinders, it also needed the catch can replumbed.

The engine was fully rebuilt by Nizpro (a well deserved plug) an re-machined, it still has an oil restrictor, now has a Tomei oil pump, standard cam baffles, no oil drain back kit, this was thrown in the bin, no more problems at all!!!

Like I said, I'm not saying this is your problem but it's definitely a possibility, do a leak down test for sure! and have the catch can plumbing checked just in case. thou it looks ok. Cheers.

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.

Well i will put my small imput,i had a mine built late 2009 from a good mate who is very very fussy builder. full forged engine no expsense spared. 7ltr hioctane sump,i am running a tomei pump but.my engine builder made 1mm restrictor,i run the drain from back of head custom, so no bashing wall, to drivers side sump,as hioctane sump has a provision on that side for it.i run the nismo oil air seperator then a hose from the nismo unit into a seperate catch can.From december 2009 to last week i have done approx 16 track days with 30-35 laps per day.my gtr is tuned 1.5 bar 512hp at wheels,It gets flogged every track day.on mich slicks 57.8 round lakeside and 57.5 round sprint track at Q.R 1650kg with me in it.All i can say is that at the end of each track day i only get 150-200 ml max in catch can which i expect with that boost and power,no smoke etc.. he has also built nearly the exact same motor for a mate with simmler power same sump same breather setup everything same as mine and he also only gets that amount of oil in can.So my view is also leakdown test and tolerences checked.Sounds like areal hed f!!k,hope you get it soughted buddy. my 2c

Well i will put my small imput,i had a mine built late 2009 from a good mate who is very very fussy builder. full forged engine no expsense spared. 7ltr hioctane sump,i am running a tomei pump but.my engine builder made 1mm restrictor,i run the drain from back of head custom, so no bashing wall, to drivers side sump,as hioctane sump has a provision on that side for it.i run the nismo oil air seperator then a hose from the nismo unit into a seperate catch can.From december 2009 to last week i have done approx 16 track days with 30-35 laps per day.my gtr is tuned 1.5 bar 512hp at wheels,It gets flogged every track day.on mich slicks 57.8 round lakeside and 57.5 round sprint track at Q.R 1650kg with me in it.All i can say is that at the end of each track day i only get 150-200 ml max in catch can which i expect with that boost and power,no smoke etc.. he has also built nearly the exact same motor for a mate with simmler power same sump same breather setup everything same as mine and he also only gets that amount of oil in can.So my view is also leakdown test and tolerences checked.Sounds like areal hed f!!k,hope you get it soughted buddy. my 2c

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.

I'm running STD dual springs with 1.1mm restrictor....

Thatt may be what I will do aswell then.

I would be severely pissed though if I put the other spring back in and it does it again...

Maybe I will do what Envy said and run the 0.9.......! Or make a 1mm?

Putting the other spring back in with a .9mm may end up flowing the same as less pressure with a larger restrictor. All a balancing act. I have an rb30 so it doesn't get revved as much meaning I am a little less concerned about oil foaming in the crank. Which is why some workshops swear by high pressure.

Matt

Trent from status told me that he ran a 1.0 mm restrickter and had trouble with insuficent oil to one of the cam journals. not sure if there was another reason for that though?

Ok, so sounds like the 1.1mm is the go, and I will leave the oil pump as is for the time being.

Can anyone tell me how to convert the standard oil pressure gauge thats in my dash to psi?? I realise its not going to be very accurate but it may give me an idea on how much oil pressure its currently running befor I pull the head off.

Trent from status told me that he ran a 1.0 mm restrickter and had trouble with insuficent oil to one of the cam journals. not sure if there was another reason for that though?

How much oil does your engine take to fill to the 'H' with the high octane sump fitted?

The reason I ask is I have been speaking alot this week with my engine builder and my tuner about my setup. They both think that my problem may be due to too much oil in my sump causing it to splash up limiting the amount of oil able to drain back down. They build alot of 26/30's, 26 amd plain 30 engines and the only difference with my setup to thiers is Iam running the high octane sump and all the engines they build run the JPC sumps.

My sump took 10 litres of oil but I did overfilled my oil to the hump on the dipstick before the recent drift day I entered.

Probly a long shot i know, but after speaking with the engine builder he assures me there would be no need to lift the head again as there must be another reason for this hapening as the engine doesn't havee enough oil pressure to warrant a 1.1mm restrictor..

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