Inlet Manifold Question

[Laser Mark 0]

I've gone some looking and haven't been able to find the answer to this question.

 

What should the condition be on the inside of the inlet manifold? I've take both parts off and inside they are covered in what looks like a thick greasey oily residue which is a bitch to clean off?

 

I have managed to borrow an ultrasonic tank for a week or so and both bits have been in for a good couple of hours removing some of the crud.

 

What I want to know is should it be really clean? My concern is that its the inlet and I don't want any of the crap getting into the valves etc....

 

I was thinking of degreasing it some more and then shotblasting the inside to clear the remaining crap out. Then obviously giving it a good rinse to remove any particles. Would this be ok?

 

Any help would be great thanks

 

Mark

[davidwort 0]

it's just the deposits from the oil breather that feeds into the airbox from the crankcase.

you could vent the crank breaker into an oil catch tank and blank off the breather pipe entrance to the airbox but ideally the crankcase needs a little suction that the inlet provides.

it could be that your engine just breathes a bit heavily, but most 16v's tend to suck through a bit of oil, especially if driven hard. If you had major engine issues and the crank case was over pressurising then loads of oil wuld blow through, but I'd imagine you've just got years of normal breathing gunk through there.

Carb cleaner should clean it off nicely, any volatile cleaner including petrol is fine to clean it off with before reassembly.

[steveo29 0]

most of the ones ive seen are black inside

 

yeah clean it up but id stay away from blasting unless you can clean it 100% as a stray bit of grit will cause more agro

 

any machine shop should be able to dunk it in something nasty and clean it up nice for cheap