VVTI 1JZGTE - JZX100 engine - Major oil leak from back of head area

[Admiral coFF33]

Hi All,
Long long LONG time since ive been on toymods, but im completely fucking stumped and need your help.

The issue is :
Under boost/Load, the 1JZ is throwing oil out the back of the head somewhere, on to the TOP SIDE of the bellhousing, which is then dribbling down and around to the base (where the drain of the bellhousing is for the R154)


Backstory :

Over the last 3-4 months since ive completed my 1JZ VVTI (X100 cut) transplant into a fully stripped Z30 drift car, ive had nothing but oil problems.
Issues have resolved after fixes to : Oil Feed for CT15b, Oil Drain for CT15b , Filter relocation kit , Cam cover seals, rear head "half moon" seals (Toyota Black) , Front main seal, Rear main seal, R154 Seal.

If i allow the car to idle, or even sit at 2k-3k rpm for minutes, it will not leak.
As soon as i apply load/boost, this leaking occurs.

This weekend just gone, Perth had a two day drift event, of which i spent my first day getting kicked off track for oil smoke pouring out.
With the addition of a relocation and cooler kit, the 1JZ holds around 6L, which after 3-4-5 hard laps of the track (drift) i would find that id lost enough oil down to 1/2 - 1/4 left on the dipstick.

Initially i thought my rear main seal had fucked out again, however after spending 8-10 hours of the first day re-doing my rear main in the pit bay i had, and the same evening i removed the cam covers, removed the rear moons and re-sealed them again. tightend enough and let it seal well over night.

Sunday morning i get back to the track and this same issues are occuring. Under boost/Load, the 1JZ is throwing oil out the back of the head somewhere, on to the TOP SIDE of the bellhousing, which is then dribbling down and around to the base (where the drain of the bellhousing is for the R154)


I checked PCV , it is working in only one direction .
My "blowby" (exhaust side breather) is NOT shooting any vapor out what so ever, near on completely dry .

I have taken out the PCV and blown through the exhaust side breather, and it is NOT blocked with air escaping on the plenum side.


The car does not blow smoke , over heat or idle strange. no issues indicating rings/valve stem seals etc are gone .


Is there ANYTHING at the back of the 1JZ VVTI head i may have missed or that would be causing oil to spill out onto the top of the bellhousing UNDER BOOST/LOAD.



cheers
John coFF33

[big_zop]

John, good to see you back and still out drifting.

There is a design flaw in the design of the cam covers that they can crack if over tightened so maybe its as simple as that.

One other aspect is that fitting new cam seals does require some sealant so maybe you need to add a bit around there.


Other than that, your comment that it happens when on boost could mean something else is up. Maybe the one way valves in the PCV system aren't working properly and allowing boost to go somewhere it shouldn't and push oil out.

[Golberg]

Have you comp tested or done a leak down on the motor?

What if you had dicky head gasket? Potentially it could suck in oil at idle and blow it out under boost

[Admiral coFF33]

Dicky metal head gasket on a 114,000kms 1997 VVti 1JZ ?

maybe.... but not likely.

Nothing has progressed on this as it pissed me off so bad at the drift weekend we had that ive shunned it into the corner of my yard until i get any sort of motorvation to pull the engine out