E30 Zone

Recently done a new head gasket, timing belt, tubular manifold on my m20. Covered about 120 miles since work done and was due for an oil change this weekend.
Its been burning a bit of oil on startup since the work, but assumed this was due to the thick oil used to rebuild the head as it clears as soon as the car is warm.
The oil check light lit up on Wednesday but level was spot on and no over temperature so guessed it was a bad connection somewhere. Oil check light was off and stayed off when I drove the car on Thursday.

Anyway, I needed to change the fuel lines to the fuel rail as well this weekend so took the airbox and afm off for access. There is quite a lot of oil all through the inlet tract (enough to pour!) and its coming from behind the butterfly.
As far as I can see there are only 2 places the oil can be coming from (rocker breather and oil drain / return) and cant see why or how it would be coming through from there in the volumes it is.

The only other thing I have changed is I had to rotate the oil filter housing to clear the new exhaust I put on. Where I have moved it the 2 pipes for the oil cooler have had to be connected the opposite way round.

So my question, is there a one way valve in the oil cooler that could be causing an increase in pressure at high temps?
What else could be causing this odd oil flow and where could it be coming from?

Ive had the rocker cover off and the head looks in great condition, no oil leaks or anything from anywhere else...

Thanks for you help.

Could be the drainage pipe from the inlet to the block is clogged up. It means removing the inlet to check it though which is a pain in the arse as your then needing to drop the coolant as well.

Taken the inlet mani off and drainage pipe is clear of blockage

Maybe if I try and break this down a bit. Does anyone know if there is a one way valve in any part of the oil cooler system, from filter housing down through the cooler? Or is thdre any reason why the pipes can't be connected the opposite way round to standard?

Failing some sort of pressure build up I really can understand how oil would be getting into the inlet manifold.

The breather pipe from the rocker cover which connects to the TB behind the butterfly, was wet with oil at the rocker end but dry at the TB end!

Makes no sense to me atm

the M20 is designed to "eat it's own crap" and you will always find oil in the TB, the rocker Breather runs direct to the TB so it's going to happen...
how much depends on the state of the bottom end !

If you're that worried, install a oil catch tank inline.

e30topless wrote: how much depends on the state of the bottom end !

And on how much sludge is in the area behind the plate riveted to the underside of the rocker cover.

Brianmoooore wrote:

e30topless wrote: how much depends on the state of the bottom end !

And on how much sludge is in the area behind the plate riveted to the underside of the rocker cover.

Well save dropping the sump im gona go with not much sludge down there. When I dropped the oil it was black but no shite in it.
Will definitely check behind the plate but again going to go with none. Maybe just the extra heavy oil I used to rebuild the head then?

In terms of quantifying the amount I would say it was pooling a fair bit in the grooves of the elephant trunk and had some as far down as the bottom of the airbox.

Anyone know about the oil cooler so I can rule that out?