[Zagi]

First of all hello to everyone! I'm proud owner of ST225 for already month and a half but i have problem with oil filter housing or oil diapgrahm..

I noticed that the housing is so dirty from oil but the top of oil diaphragm is dry and clean but i also noticed a little vacum noise while opening oil dipstick when engine is running..

So my only question is what could cause housing to be so dirty from oil? And should i change diapgragm or whole filter housing?

 

[Cosmic73]

Hey new member.
It's probay from oil dribbling down the filter housing when the filter is changed. Mine is minging.

 

[Bigayal]

They are a common problem area on these , if you have a noise when dipstick is pulled then just change it all

Ford Focus Mk2 RS and ST225 Genuine Oil Filter Housing

Ford Focus Mk2 ST/RS Genuine Oil Filter Housing Available with or without Breather Hose. *Please note images are generic and may not show the exact product*

www.aandkmotorsport.com

 

[Dabhand16]

If the diaphragm has gone the whine will go whenthe dipstick is pulled.

 

[Andy and Kirsty]

You should have a small vacuum when you take the dipstick out thats totally normal and part of the PCV system. If the fiter housing diaphragm goes you get a massive vacuum that causes screeching noise when the dipstick is in. Yours looks like its blowing oil out of the plastic lid on the filter housing which can be a sign of too much pressure in the crankcase. Could be the pistons, piston rings or valve guide seals allowing pressure into the crankcase or the metal gasket between the intake manifold and the head. The gasket has reed valves in it that stop pressure getting into the system on boost but allow the vacuum when the throttle is shut. The reed valves can get bent or break allowing pressure into the filter housing. See pictures, the reed valves are ringed in red. Gasket is 9439 in the drawing.

 

[Zagi]

You should have a small vacuum when you take the dipstick out thats totally normal and part of the PCV system. If the fiter housing diaphragm goes you get a massive vacuum that causes screeching noise when the dipstick is in. Yours looks like its blowing oil out of the plastic lid on the filter housing which can be a sign of too much pressure in the crankcase. Could be the pistons, piston rings or valve guide seals allowing pressure into the crankcase or the metal gasket between the intake manifold and the head. The gasket has reed valves in it that stop pressure getting into the system on boost but allow the vacuum when the throttle is shut. The reed valves can get bent or break allowing pressure into the filter housing. See pictures, the reed valves are ringed in red. Gasket is 9439 in the drawing.

Thank you for information,that's why i was confused becouse i saw that everything around oil diapgragm is dry but didn't understand why is the filter housing so dirty..i will order the metal gasket for intake manifold and write back if it solves my problem!

 

[Andy and Kirsty]

Thank you for information,that's why i was confused becouse i saw that everything around oil diapgragm is dry but didn't understand why is the filter housing so dirty..i will order the metal gasket for intake manifold and write back if it solves my problem!

I would also get a compression and leak down test done to rule out damage to the pistons and bores.

 

[Andy and Kirsty]

Actually before you do any of that take the plastic top off the housing, the big squareish bit. It just clips on all the way round so you can remove it if youre careful. Then run a bead of silicone sealer round the joint and put it back together. Let it set for a few hours and see if that helps. It can just be oil weeping out.

 

[Cosmic73]

You should have a small vacuum when you take the dipstick out thats totally normal and part of the PCV system. If the fiter housing diaphragm goes you get a massive vacuum that causes screeching noise when the dipstick is in. Yours looks like its blowing oil out of the plastic lid on the filter housing which can be a sign of too much pressure in the crankcase. Could be the pistons, piston rings or valve guide seals allowing pressure into the crankcase or the metal gasket between the intake manifold and the head. The gasket has reed valves in it that stop pressure getting into the system on boost but allow the vacuum when the throttle is shut. The reed valves can get bent or break allowing pressure into the filter housing. See pictures, the reed valves are ringed in red. Gasket is 9439 in the drawing. View attachment 910757
View attachment 910759
View attachment 910758

I always wondered what those things were for,

 

[Zagi]

I would also get a compression and leak down test done to rule out damage to the pistons and bores.

Made compression test and shows only 90psi so not good..

 

[trevorb]

What? Are all 5 cyls only indicating 90psi - if so I would double check with another compression tester gauge

 

[Zagi]

Sorry for late reply,work take so much time

Anyway today i was at mechanic and we did compression test and on all cylinders it showed at about 130psi..

 

[Andy and Kirsty]

Sorry for late reply,work take so much time

Anyway today i was at mechanic and we did compression test and on all cylinders it showed at about 130psi..

Thats not too bad but you need to do a leak down test too.

 

[Zagi]

Soo update on the oil filter housing..i bought a new one and mount it but i still get vacum noise from oil dipstick and oil cap and the RPM slow down a little bit when i open it..so is that vacum noise normal or?

 

[Alb]

A small amount of vacuum is normal because the crankcase is being scavenged by the PCV system.

 

[marco_ST]

Soo update on the oil filter housing..i bought a new one and mount it but i still get vacum noise from oil dipstick and oil cap and the RPM slow down a little bit when i open it..so is that vacum noise normal or?

When the engine is running open up the oil cap - if the pcv is functioning as it should you should feel like it is sucking the oil cap back in. When it is the opposite you would hear and notice the pressure coming out. When you changed the oil filter housing did you cleaned the conecting hoses too?

 

[Zagi]

When the engine is running open up the oil cap - if the pcv is functioning as it should you should feel like it is sucking the oil cap back in. When it is the opposite you would hear and notice the pressure coming out. When you changed the oil filter housing did you cleaned the conecting hoses too?

I cleaned only the little one which is connected above intake manifold..but then it is normal becouse it is sucking the oil cap back in