There's no valve in the CrankCase Ventilation (CCV) system, the rear tube
is just a manifold vacuum tube with a metering orifice to limit the amount
of vacuum applied to the crankcase (See _Chilton's_ `84-98 Cherokee
manual, Sec. 4-2 "Emission Controls" for description and testing method).
The front tube is a fresh air breather and comes in two parts, Left Vacuum
Assembly and Right Vacuum Assembly.

Follow the link Mike gives below for the Mopar part numbers, or read the
following from a different thread 9 days ago for the Balkamp part numbers.
Shop around, you might save a few bucks -- and I'm betting that they are
all Balkamp parts anyway. I paid US$41 for all three parts at NAPA, the
rear assembly only cost US$11, so you have to decide what your time is
worth.

<URL:http://www.google.com/groups?selm=Pine.NEB.4.58.0404171100130.7662%40pan ix1.panix.com>



On Mon, 26 Apr 2004, William Oliveri wrote:

> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
>
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill
>
>
>

 

There's no valve in the CrankCase Ventilation (CCV) system, the rear tube
is just a manifold vacuum tube with a metering orifice to limit the amount
of vacuum applied to the crankcase (See _Chilton's_ `84-98 Cherokee
manual, Sec. 4-2 "Emission Controls" for description and testing method).
The front tube is a fresh air breather and comes in two parts, Left Vacuum
Assembly and Right Vacuum Assembly.

Follow the link Mike gives below for the Mopar part numbers, or read the
following from a different thread 9 days ago for the Balkamp part numbers.
Shop around, you might save a few bucks -- and I'm betting that they are
all Balkamp parts anyway. I paid US$41 for all three parts at NAPA, the
rear assembly only cost US$11, so you have to decide what your time is
worth.

<URL:http://www.google.com/groups?selm=Pine.NEB.4.58.0404171100130.7662%40pan ix1.panix.com>



On Mon, 26 Apr 2004, William Oliveri wrote:

> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
>
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill
>
>
>

 

There's no valve in the CrankCase Ventilation (CCV) system, the rear tube
is just a manifold vacuum tube with a metering orifice to limit the amount
of vacuum applied to the crankcase (See _Chilton's_ `84-98 Cherokee
manual, Sec. 4-2 "Emission Controls" for description and testing method).
The front tube is a fresh air breather and comes in two parts, Left Vacuum
Assembly and Right Vacuum Assembly.

Follow the link Mike gives below for the Mopar part numbers, or read the
following from a different thread 9 days ago for the Balkamp part numbers.
Shop around, you might save a few bucks -- and I'm betting that they are
all Balkamp parts anyway. I paid US$41 for all three parts at NAPA, the
rear assembly only cost US$11, so you have to decide what your time is
worth.

<URL:http://www.google.com/groups?selm=Pine.NEB.4.58.0404171100130.7662%40pan ix1.panix.com>



On Mon, 26 Apr 2004, William Oliveri wrote:

> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
>
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill
>
>
>

 

Nope....
;-)

You are dealing with 2 totally different engines that 'breath' in 2
totally different ways.

The 4.2 L engine uses a PCV (positive crankcase ventilation) valve from
the front of the valve cover that sucks through the carburetor base
plate. Along the way there is a T in the line for the Charcoal Canister
which is the gas tank vent. This PCV suction is balanced to have the
canister kick in when ported vacuum comes up high. (at speed basically)

The intake for the engine on the 4.2 comes from the air filter and goes
to the rear grommet. That is just an open hose that sucks filtered air.

The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
a small hole in the rear grommet of the 4.0 valve cover with a small
plastic tube in it that goes to the intake manifold. This small hole is
'metered' so a certain amount of suction is always there. The hole can
be cleaned out with a paper clip.

Then the intake for the engine comes from the air filter and goes to the
front grommet on the valve cover.

The 4.0 engine does not tie in the charcoal canister to the CCV system,
it uses a different canister all together that purges through a special
fitting on the 4.0 air filter box.

Basically you have to use one system or the other, you cannot 'easily'
mix and match them and expect the engine to run right.

I have heard of folks getting a PCV valve for the 4.0 cover and
converting the cover over to the 4.2 system.

I think this is easier and cheaper than going the other way. Just the
right canister for the 4.0 cover is $100.00 or more, where a couple
grommets and chunks of hoses for a PCV are cheap.

I do know that folks have posted here about switching the CCV over to a
PCV on a 4.0 valve cover, maybe ask that specific question.

Mike

William Oliveri wrote:
>
> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill

 

Nope....
;-)

You are dealing with 2 totally different engines that 'breath' in 2
totally different ways.

The 4.2 L engine uses a PCV (positive crankcase ventilation) valve from
the front of the valve cover that sucks through the carburetor base
plate. Along the way there is a T in the line for the Charcoal Canister
which is the gas tank vent. This PCV suction is balanced to have the
canister kick in when ported vacuum comes up high. (at speed basically)

The intake for the engine on the 4.2 comes from the air filter and goes
to the rear grommet. That is just an open hose that sucks filtered air.

The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
a small hole in the rear grommet of the 4.0 valve cover with a small
plastic tube in it that goes to the intake manifold. This small hole is
'metered' so a certain amount of suction is always there. The hole can
be cleaned out with a paper clip.

Then the intake for the engine comes from the air filter and goes to the
front grommet on the valve cover.

The 4.0 engine does not tie in the charcoal canister to the CCV system,
it uses a different canister all together that purges through a special
fitting on the 4.0 air filter box.

Basically you have to use one system or the other, you cannot 'easily'
mix and match them and expect the engine to run right.

I have heard of folks getting a PCV valve for the 4.0 cover and
converting the cover over to the 4.2 system.

I think this is easier and cheaper than going the other way. Just the
right canister for the 4.0 cover is $100.00 or more, where a couple
grommets and chunks of hoses for a PCV are cheap.

I do know that folks have posted here about switching the CCV over to a
PCV on a 4.0 valve cover, maybe ask that specific question.

Mike

William Oliveri wrote:
>
> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill

 

Nope....
;-)

You are dealing with 2 totally different engines that 'breath' in 2
totally different ways.

The 4.2 L engine uses a PCV (positive crankcase ventilation) valve from
the front of the valve cover that sucks through the carburetor base
plate. Along the way there is a T in the line for the Charcoal Canister
which is the gas tank vent. This PCV suction is balanced to have the
canister kick in when ported vacuum comes up high. (at speed basically)

The intake for the engine on the 4.2 comes from the air filter and goes
to the rear grommet. That is just an open hose that sucks filtered air.

The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
a small hole in the rear grommet of the 4.0 valve cover with a small
plastic tube in it that goes to the intake manifold. This small hole is
'metered' so a certain amount of suction is always there. The hole can
be cleaned out with a paper clip.

Then the intake for the engine comes from the air filter and goes to the
front grommet on the valve cover.

The 4.0 engine does not tie in the charcoal canister to the CCV system,
it uses a different canister all together that purges through a special
fitting on the 4.0 air filter box.

Basically you have to use one system or the other, you cannot 'easily'
mix and match them and expect the engine to run right.

I have heard of folks getting a PCV valve for the 4.0 cover and
converting the cover over to the 4.2 system.

I think this is easier and cheaper than going the other way. Just the
right canister for the 4.0 cover is $100.00 or more, where a couple
grommets and chunks of hoses for a PCV are cheap.

I do know that folks have posted here about switching the CCV over to a
PCV on a 4.0 valve cover, maybe ask that specific question.

Mike

William Oliveri wrote:
>
> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill

 

Nope....
;-)

You are dealing with 2 totally different engines that 'breath' in 2
totally different ways.

The 4.2 L engine uses a PCV (positive crankcase ventilation) valve from
the front of the valve cover that sucks through the carburetor base
plate. Along the way there is a T in the line for the Charcoal Canister
which is the gas tank vent. This PCV suction is balanced to have the
canister kick in when ported vacuum comes up high. (at speed basically)

The intake for the engine on the 4.2 comes from the air filter and goes
to the rear grommet. That is just an open hose that sucks filtered air.

The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
a small hole in the rear grommet of the 4.0 valve cover with a small
plastic tube in it that goes to the intake manifold. This small hole is
'metered' so a certain amount of suction is always there. The hole can
be cleaned out with a paper clip.

Then the intake for the engine comes from the air filter and goes to the
front grommet on the valve cover.

The 4.0 engine does not tie in the charcoal canister to the CCV system,
it uses a different canister all together that purges through a special
fitting on the 4.0 air filter box.

Basically you have to use one system or the other, you cannot 'easily'
mix and match them and expect the engine to run right.

I have heard of folks getting a PCV valve for the 4.0 cover and
converting the cover over to the 4.2 system.

I think this is easier and cheaper than going the other way. Just the
right canister for the 4.0 cover is $100.00 or more, where a couple
grommets and chunks of hoses for a PCV are cheap.

I do know that folks have posted here about switching the CCV over to a
PCV on a 4.0 valve cover, maybe ask that specific question.

Mike

William Oliveri wrote:
>
> Oh, Ok.. It finally clicked. The rear valve on the valve cover is the PCV
> (Positive Crankcase Ventilation) and the tube that goes to the intake
> manifold is the CCV (Crankcase Ventilation) Tube. Is that right?
>
> I was at Chrysler parts today and asked them what the tube was called and
> they said, with a straight face, "the tube that goes between the PCV valve
> and the intake manifold".
>
> LOL. Some wonder why I'm so farked up.
>
> Thanks,
>
> Bill
>
> "Mike Romain" <romainm@sympatico.ca> wrote in message
> news:408DD216.D92DAD67@sympatico.ca...
> > That is a CCV valve. It should be cleaned and or replaced. The hole in
> > the rubber can be cleaned with a paper clip.
> >
> > Check here for part numbers.
> >
> > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> >
> > William Oliveri wrote:
> > >
> > > Hi all,
> > >
> > > I just looked at the 4.0L valve cover which will be going on my
> 4.2/4.0
> > > combo and I noticed the PCV valve was clogged with gook (on the inside
> of
> > > the valve cover are three screws which allow the PCV casing to come away
> > > from the valve exposing the PCV Valve itself). Can the valve:
> > >
> > > 1. Be cleaned satisfactorily?
> > >
> > > or
> > >
> > > 2. Be replaced with a new valve?
> > >
> > > I seem to remember reading that these cannot be replaced but not sure
> either
> > > all of them are like that or only some.
> > > Looks like it was made to as it has access to the inside.
> > >
> > > Thanks for any help.
> > >
> > > Bill

 

See inline....

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:408E6EDD.A0F4C209@sympatico.ca...
> Nope....
> ;-)

So I'm still Farked up!! :-)

> The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
> a small hole in the rear grommet of the 4.0 valve cover with a small
> plastic tube in it that goes to the intake manifold. This small hole is
> 'metered' so a certain amount of suction is always there. The hole can
> be cleaned out with a paper clip.

This I understand. My MPI Kit has this.

> Then the intake for the engine comes from the air filter and goes to the
> front grommet on the valve cover.

This I understand. My MPI Kit has this.

> The 4.0 engine does not tie in the charcoal canister to the CCV system,
> it uses a different canister all together that purges through a special
> fitting on the 4.0 air filter box.

This I got. MPI Kit has this.

What I'm not understanding is that in the article there is more parts going
from the front gromet than what I have. Perhaps this is a difference
between a stock 4.0L and the MPI kit.

I have only one line coming from the front gromet of the valve cover to the
air breather assembly and attaches to a fitting. On the other side of that
fitting is the tube that goes to the charcoal canister. The fitting is
basically a T fitting.

I'll try to get a pic of what I have to show you but it's basically how I
discribed.

Thanks,

Bill


> Basically you have to use one system or the other, you cannot 'easily'
> mix and match them and expect the engine to run right.
>
> I have heard of folks getting a PCV valve for the 4.0 cover and
> converting the cover over to the 4.2 system.
>
> I think this is easier and cheaper than going the other way. Just the
> right canister for the 4.0 cover is $100.00 or more, where a couple
> grommets and chunks of hoses for a PCV are cheap.
>
> I do know that folks have posted here about switching the CCV over to a
> PCV on a 4.0 valve cover, maybe ask that specific question.
>
> Mike
> > > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> > >

 

See inline....

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:408E6EDD.A0F4C209@sympatico.ca...
> Nope....
> ;-)

So I'm still Farked up!! :-)

> The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
> a small hole in the rear grommet of the 4.0 valve cover with a small
> plastic tube in it that goes to the intake manifold. This small hole is
> 'metered' so a certain amount of suction is always there. The hole can
> be cleaned out with a paper clip.

This I understand. My MPI Kit has this.

> Then the intake for the engine comes from the air filter and goes to the
> front grommet on the valve cover.

This I understand. My MPI Kit has this.

> The 4.0 engine does not tie in the charcoal canister to the CCV system,
> it uses a different canister all together that purges through a special
> fitting on the 4.0 air filter box.

This I got. MPI Kit has this.

What I'm not understanding is that in the article there is more parts going
from the front gromet than what I have. Perhaps this is a difference
between a stock 4.0L and the MPI kit.

I have only one line coming from the front gromet of the valve cover to the
air breather assembly and attaches to a fitting. On the other side of that
fitting is the tube that goes to the charcoal canister. The fitting is
basically a T fitting.

I'll try to get a pic of what I have to show you but it's basically how I
discribed.

Thanks,

Bill


> Basically you have to use one system or the other, you cannot 'easily'
> mix and match them and expect the engine to run right.
>
> I have heard of folks getting a PCV valve for the 4.0 cover and
> converting the cover over to the 4.2 system.
>
> I think this is easier and cheaper than going the other way. Just the
> right canister for the 4.0 cover is $100.00 or more, where a couple
> grommets and chunks of hoses for a PCV are cheap.
>
> I do know that folks have posted here about switching the CCV over to a
> PCV on a 4.0 valve cover, maybe ask that specific question.
>
> Mike
> > > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> > >

 

See inline....

"Mike Romain" <romainm@sympatico.ca> wrote in message
news:408E6EDD.A0F4C209@sympatico.ca...
> Nope....
> ;-)

So I'm still Farked up!! :-)

> The 4.0 engine uses a CCV valve (closed crankcase ventilation). This is
> a small hole in the rear grommet of the 4.0 valve cover with a small
> plastic tube in it that goes to the intake manifold. This small hole is
> 'metered' so a certain amount of suction is always there. The hole can
> be cleaned out with a paper clip.

This I understand. My MPI Kit has this.

> Then the intake for the engine comes from the air filter and goes to the
> front grommet on the valve cover.

This I understand. My MPI Kit has this.

> The 4.0 engine does not tie in the charcoal canister to the CCV system,
> it uses a different canister all together that purges through a special
> fitting on the 4.0 air filter box.

This I got. MPI Kit has this.

What I'm not understanding is that in the article there is more parts going
from the front gromet than what I have. Perhaps this is a difference
between a stock 4.0L and the MPI kit.

I have only one line coming from the front gromet of the valve cover to the
air breather assembly and attaches to a fitting. On the other side of that
fitting is the tube that goes to the charcoal canister. The fitting is
basically a T fitting.

I'll try to get a pic of what I have to show you but it's basically how I
discribed.

Thanks,

Bill


> Basically you have to use one system or the other, you cannot 'easily'
> mix and match them and expect the engine to run right.
>
> I have heard of folks getting a PCV valve for the 4.0 cover and
> converting the cover over to the 4.2 system.
>
> I think this is easier and cheaper than going the other way. Just the
> right canister for the 4.0 cover is $100.00 or more, where a couple
> grommets and chunks of hoses for a PCV are cheap.
>
> I do know that folks have posted here about switching the CCV over to a
> PCV on a 4.0 valve cover, maybe ask that specific question.
>
> Mike
> > > http://www.off-road.com/jeep/cheroke...ltr/blowby.htm
> > >