Oil Issue

[monga]

So I've got a RB26DETT which recently has being rebuilt making reasonable power, the initial problem was a bearing and the motor was rebuilt and the car was perfect for around 15,000 KM.

So I decided to check my oil and overflow bottle one night to my shock I had found bucket loads of black oil in my overflow and huge amounts in my radiator, so back down the shop I went and the diagnoses was the head gasket, which I thought was odd because the car just had a fresh metal one installed with the rebuild.

Anyhow the car seems fine initially after a new HKS head stopper is put in and I check the situation again with another 300-400km done, to see more oil being pumped up again into the radiator and into the overflow, also I think coolant was vanishing. So back to the workshop and we do a study to find on low boost little oil seems to be pumped up, but on high its clear and the motor's dip stick is low.

So the problem appears to be the block is cracked, now the block has had a lot of money and preparation and only pushed 400hp any around 15,000km, but it happens so a new block arrives.

So another new HKS head stopper is installed with other parts while the bottom end is done and the new block is installed with the power FC and tuned and the car makes good power and seems okay.

After 2500km I seem to think oil is being pumped up again and I see oil again in the overflow, this time we used some distilled water and it made a good combo with the oil. So we car travels to 4,000km and the oil is low and the car goes in for the service and change over. As a note I found after I got the car back it seemed to drink alot of extra coolant?

So the car is back around April 10 or so now I have traveled 2000km and the oil is now has dropped a noticeable amount of the dipstick and appears to have floated into the over flow and radiator a bit

Now: the head has being checked twice I pretty sure with the head gasket issue first and the second block

So the workshop thinks it may be something to be with the turbo? I thought they were checked first when the motor was taken out again though?

Note the turbos are HKS 2530'S in good knick

So all advice and opinions would be great to assist in my problem

Regards,

Clint

[R34GTFOUR]

bloody hell you've had some bad luck

i would pressurise the radiator (whilst still connected to the engine) like a leak down test, and see if it leaks any pressure. If it does, then trace where its leaking from and take it from there. It would be extremely strange that its the turbo (what turbo/s are you running?)

You would assume that the block is fine since its a new item, but i would still be a little concerned with the head and head gasket, cause if the workshop are the ones that checked it and said its fine, but they can't get your car running right i wouldnt be too confident in their work.

Take it to them and let them know its not right, then pressurise your cooling system, theres obviously a leak somewhere between your oil and coolant.

Also is your oil milky at all?

Edited March 25, 2008 by R34GTFOUR

[monga]

The radiator has being pressurized is fine, also the oil is not milky, just like fresh oil being poured in there.

Also is there enough pressure in the head to pump a lot of oil in the cooling ect?

[R34GTFOUR]

The radiator has being pressurized is fine, also the oil is not milky, just like fresh oil being poured in there.

Also is there enough pressure in the head to pump a lot of oil in the cooling ect?

your oil pressure will go anywhere from 40psi upto 90psi when your driving (depending on rpm), on the other hand your cooling system will only be at a fraction of that, normally around the 7psi mark. So if there isa leak somewhere between the oil and coolant, the oil is going to be pumped quite quickly into your coolant since its at a higher pressure.

at what pressure did you pressurise the radiator? and how long did you leave it connected for? there would have to be a leak otherwise oil wouldnt be contaminting the coolant

Edited March 25, 2008 by R34GTFOUR

[monga]

It was left there over night resulting in no leak

Heater exhange has being removed also

Anyone else with some knowledge want to post?

[White GTS-T]

Have you done a compression test and leakdown test?

Do you have a catch can?

Have you pulled off the cooler piping to check for blow by?

And also when you did pull the head off was there water in any of the pistons?

[farch]

It was left there over night resulting in no leak

Heater exhange has being removed also

Anyone else with some knowledge want to post?

So you did check the little sandwich cooler in the oil filter mount......

[monga]

Have you done a compression test and leakdown test?

Do you have a catch can?

Have you pulled off the cooler piping to check for blow by?

And also when you did pull the head off was there water in any of the pistons?

Yes mate, that is all fine and the motor is perfect, but I don't have a catch can

So you did check the little sandwich cooler in the oil filter mount......

No I havnt

Also what I don't get is how the oil dipstick can be low IE 1.1.5litres, but nothing is being sprayed out the over flow?

[Godzilla32]

Id be checking the sandwiched heat exchanger. That workshop is bullshit! I'd be absolutely fuming!

[DCIEVE]

do you know what piston/bore clearance the machinist worked too... will still have good leakdown and compression but will burn a bit of oil

not that it helps you with the oil in the coolant problem

[Jmaac]

Have you had the head itself pressure tested? it could be cracked also

[monga]

Id be checking the sandwiched heat exchanger. That workshop is bullshit! I'd be absolutely fuming!

I will get that checked also mate

do you know what piston/bore clearance the machinist worked too... will still have good leakdown and compression but will burn a bit of oil

not that it helps you with the oil in the coolant problem

Well the car didnt burn any oil for the first 10,000km, I doubt it can relate to that?

Have you had the head itself pressure tested? it could be cracked also

This has being tested twice so I imagine its okay

Thanks for the help people, more assistance the better!

[giant]

i had oil getting into the radiator in one of our engines and it ended up being the cylinder head we had it pressure tested , refitted still did it , we then threw it in the bin and got another one!

but strangely our water was going milky so not 100 percent sure.

also was you new block brand new?

[monga]

No, had travelled 7,000km~ but tested prepped ect ect,

Giant I guess it goes milky, but soon as it the oil hits the radiator it appears black then the combination changes the colour? Also did you find more was getting pumped into it with more boost and power?

No one has mentioned a turbo issue? comments there?

[giant]

the other issue we have had was the block cracking at the head stud holes in the top of the block outward to the water jacket, this is very common and can be from over tensioning the head bolts or using after market headstuds and when they are tightened down they can bottom out if not careful and crack the block! this is an issue as four of the headbolts have oil flowing around them up into the head and if cracked flows straight into the waterjacket.

if not assembled correctly the block could get cracked from brandnew!

[monga]

Also with the head to crack it would have to be really hot ect?

Mines car has never over heated ect

[datsqik]

From what I've seen of Clints oil problem is that it seems to get worse when higher boost/hp is used so it probably indicates that a crack is opening up when things get hotter or more stressed. It gets oil into the water but not the other way around and it has done it with 2 different blocks. The head gaskets seem to be sealing. The head has been pressure tested. The coolant system has been pressure tested. The only other area I can think of where the water and oil are close is in the turbo. So you might have to get the turbos pressure tested but if its only doing it when things get hot then it might not show up. The same goes for the head, it might not show up until it gets very hot.

[monga]

How hot does the head reach like temp wise?