Mousse-Be-Gone

[Ed Lijewski]

Some thoughts on why oil vapor/froth "mousse" sometimes appears inside Scorpio passenger side valve covers, with a couple of tips on preventing it follow.

The Scorpio PCV system has a weak design for evacuating oil vapor the passenger side head/valve train. Crankcase vapors to that area are intended to be vacuumed away into the engine intake via the hose attached to the oil filler cap which runs to the air box on the driver's side of the engine compartment.

Passenger side Valve Cover oil filler breather cap hose:



Passenger side VC oil filler breather hose to air intake box:



Passenger side VC oil breather cap hose feed into air intake box:



PCV on driver's side VC:



PCV close-up; The driver's side head and valve train are well scavenged of oil vapor/froth by the direct connection to intake vacuum.



PCV hose connected directly to intake manifold:

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Scavenging of oil vapors/froth from the passenger side VC relies on air box vacuum induced into the oil breather/filler cap hose, and a good seal of the breather/filler cap into the VC oil fill spout. If there is a filter in the breather hose exit manifold it should be removed to enable free flow of air box intake vacuum to that hose end.

[URL=http://s60.photobucket.com/user/PC_800/ ... b.jpg.html]

By now all Scorpio oil breather/fill cap O-rings have lost their ability to seal tightly due to engine heat cycles. Passenger side VC oil filler cap showing O-ring:



I've searched for but haven't yet found a replacement O-ring for the VC oil breather/filler cap. Until I find a replacement I'm using a ribbon of electrical tape around the cap and filler neck meeting edges to prevent loss of vacuum to that VC from the air box. The only occasional need to remove the cap to add oil and a new ribbon of tape is a minor inconvenience if oil vapor scavenging from that VCA is improved.

VC Breather/Filler Cap With Tape Sealing the Cap to the VC Spout:



A more systemic fix could be to attach the oil breather/filler cap hose directly to the hose from the PCV to the intake manifold using a tee fitting.


YMMV

[MercMike]

http://www.allorings.com/material_selection.htm

[FocusSVT]

Thanks for the nicely detailed, thorough post. I will have to take a look at my setup and see how it is doing.

Thanks again!

[Ed Lijewski]

New O-rings for VC breather/oil filler cap:



The new one is a snug fit on both the filler cap and the VC tube.

$6 for one O-ring shipped.

YMMV

[John Brennan]

You know, it's the little details like this that can make the difference between a tired, old car, and a treasure. Thanks for the writeup, nicely done.

[Bob Weir]

Ed

And I thought "mousse" in the VC was from either a cracked head or bad head gasket.

You need your tubes cleaned - professionally!

Regarding the correct size rubber ring; I better stop before the editor erases my post...

[John Brennan]

Ed

And I thought "mousse" in the VC was from either a cracked head or bad head gasket.

You need your tubes cleaned - professionally!

Regarding the correct size rubber ring; I better stop before the editor erases my post...

No, go on-- if there is erroneous information, or if you have a different opinion/experience, by all means, let us know... Ed means well, and is going by what he knows. One of the main purposes of this forum is to contribute experience, whether personal or referred, so as to find out the truth about something.

[Bob Weir]

John

Ed, and many others know I have a cracked head and a few loose gaskets; haven't had my tubes professionally cleaned since Viet Nam; and haven't used the proper size rubbers attested by my 3 children.

[Mike McCreight]

John

Ed, and many others know I have a cracked head and a few loose gaskets; haven't had my tubes professionally cleaned since Viet Nam; and haven't used the proper size rubbers attested by my 3 children.

It's early, but this may be my front runner for post of the year.
Thanks, Bob.
You're a credit to this particular brand of dementia.

[Ed Lijewski]

Yeah, I also thought they resemble a rubber, if you buy size Micro-- Bwahahahaha.

But hold the patronizing from all sides, or show me you better understand the Scorpio PCV system.

Saying the appearance of mousse is from a cracked head or blown head gasket may/may be partially correct. But every head crack or head gasket leak doesn'result in vapors of coolant and oil. Head gasket leaks occur between cylinders as well as into coolant passages. In the latter case, there is most likely a rapid if not immediate symptom of sharply increased coolant temperatures, which you may catch before greater engine damage occurs if you check the dash temp gauge often. Or the coolant in the reservoir boils on shutdown for an unrecognized reason. So typically a gasket leak into coolant should be caught before thick mousse deposits occur as the car likely becomes unreliable for common use beyond to and from 7-11 (for a pack of cancer sticks in Bob's case... ).

Head gasket leaks between cylinders affect performance especially at idle if the leak is small or throughout the RPM range if larger.

Cracked heads where the crack runs to a coolant passage typically cause coolant temp spikes and reservoir coolant bubblng as well, a a result of pressure loss and air introduced into the system.

But...now think about this...the PCV system should remove vapors from both upper sides of a v-shape engine. And will if the full system is working well as designed. Think about this...many if not all mousse issues on Scorpios discovered and reported on this Forum were on the passenger side valve cover; althoughcertainly cracked heads and blown head gaskets could occur on either or even both sides of the engine. Mousse accumulation, or serious mousse at least however, should be unlikely if the passenger side of the PCV system is working as intended.

That shouldn't be assumed to be functioning properly without benefit of periodic inspection and maintenance of the PCV system...which isn't just cleaning or installing a new PC Valve. The "PC" stands for positive crankcase ventilation; positive means allowing a vacuum, sufficient to draw out vapors produced within the engine. The Scorpio PCV mounted on the driver's side vc induces full intake vacuum into that side of the engine. But on the passenger side the vacuum is induced by the Venturi effect created in the airbox as outside air drawn into the air box passes upward and over the vent in the air box for the hose running to the passenger side vc breather/filler cap. Any obstruction or leak in the course of that induced vacuum results in less or possibly a loss of vacuum to that vc. And that effect allows vapors to remain and produce deposits and even mousse build up over engine cycles...even/Even/EVEN in an otherwise healthy engine, with no head cracks into the cooling system or head gasket leaks into coolant passages.

A few years ago, 6/7/8 IIRC, Toyota had huge/Huge issues with oil gelling as it was called by some in V-6s due to failure to clean/service the PCV system (you can look it up). Those engines did not have car ked heads or blown head gaskets.

So, what I offered in this Topic essentially are reminders to understand, service, and maintain the weaker part of the Scorpio PCV system, or take your chances and see if mousse develops and then have to clean it up and hope that the valve train and maybe even cam bearings weren't hurt by it.

And my tips was at above should also have pointed to the need to blow out any liquid or crud that over time accumulates in the hose from their breather/filler cap to the air box due to how it sags at a low point near the center of the engine.

Or the joke will be on you

(Overlook all typos as I wrote this on my phone.)

YMMV

[Bob Weir]

Ed wrote <Yeah, I also thought they resemble a rubber, if you buy size Micro>
Are u making this comment based on assumptions or Col’s inebriated comments.

I’ll pass on this thread. It pains me to remember hours and money wasted regarding my misdiagnosis of my Scorp’s engine. Lesson learned = nfg cam bearings, not nfg head[s]!

Recently my “burgendy bitch” Scorp is continually taking me down the malfunctioning electrical path. Stripping for parts and the crusher are getting closer and closer for the burgendy bitch.

[Ed Lijewski]

Bobarino:

No one here believes you won't or can't solve BB's issues. (You've kept Col purring through thick and thin-and without benefit of a service manual or break-out board, after all ).

Your Scorpio head(s) could have been cracked but Magnafluxing them to locate that wouldn't have been worth it once they were already removed and the new ones were in hand ready for install.

Breathe deep and carry on. Again.

YMMV

[brokencase]

Sorry to revitalize this topic..

But as I read through the initial post I am confused.

Stated and understood:
1) We have full manifold vacuum on the driver's side valve cover.
2) We have the passenger's side valve cover with a larger hose going to ATMOSPHERIC side of the air cleaner.

But not mentioned is the fact that the spaces in each valve cover is "connected" via the lifter valley via the push rod holes in the head.

I proclaim that air is ENTERING the passenger's side and being scavenged through to the driver's side.

The original poster suggest removing any filter found in the air cleaner box where the hose to the passenger side breather goes.
I think it is unwise to remove this filter.

I have not studied the the breather assembly on the passenger side, but I think it may have an intentional restriction.

This is consistent with other PVC systems I have observed. Vacuum is applied, but it cannot be full manifold vacuum, as this is too strong.
You have to leak some air in elsewhere through a restriction.

[Bob Weir]

Hi broken case & Ed,
I've had a few wines and I couldn't resist jammed uall, but it's a relevant discussion especially for the newbies
I KNOW u all will correct my transgressions and incorrect suggestions & comments

broken case wrote:

Sorry to revitalize this topic..
U r 1 sorry inde
But as I read through the initial post I am confused.
U r confused- the MCA Board's gonna make a sticky of this statement

Stated and understood:
1) We have full manifold vacuum on the driver's side valve cover.
R u sure about "FULL"?

2) We have the driver's side valve cover with a larger hose going to ATMOSPHERIC side of the air cleaner.
Correction: Passenger side has large hose going to air box, Driver's side has PCV to CANP to 1] Fuel tank & 2] Carbon canister.

But not mentioned is the fact that the spaces in each valve cover is "connected" via the lifter valley via the push rod holes in the head.
Ok do ke

I proclaim that air is ENTERING the passenger's side and being scavenged through to the driver's side.
Correction: Air is being sucked into air box by eng intake and sucked out of Passenger side VC through large hose.

The original poster suggest removing any filter found in the air cleaner box where the hose to the passenger side breather goes.
I think it is unwise to remove this filter.
Assumption: Ed's suggesting cleaning out screen in oil filler cap and its hose. He's into cleanliness!

I have not studied the the breather assembly on the passenger side, but I think it may have an intentional restriction.
We all have "internal restrictions"! Ask Col
This is consistent with other PVC systems I have observed. Vacuum is applied, but it cannot be full manifold vacuum, as this is too strong.
You have to leak some air in elsewhere through a restriction.
They're Merkurs - they're made with vac & elec gremlins!

Col and Amanda have returned home and have stories to tell that I must be attentive.
Talk with all soon. Have Happy Holidays. Best wishes to u all... Love & kisses fro the girls...

EDIT Wednesday AM. It stopped raining so I can open the Scorpio and verify my comments. I'm sure someone will correct me.

[brokencase]

Bob, You sound pretty wasted in that post...

The valve covers are connected space. You have high vacuum on the driver's side. You have non-vacuum connection to the air cleaner on the passenger side. How else can the air move? Think it through.

Look at this then weep...
http://www.agcoauto.com/content/news/p2_articleid/197

And then cut the "newbie" crap, I have many posts in the IMON archives that go back to '98!